{"gene":"CASR","run_date":"2026-06-09T22:57:17","timeline":{"discoveries":[{"year":2000,"finding":"CASR encodes a plasma membrane G protein-coupled receptor expressed in parathyroid chief cells and kidney tubule cells that senses small changes in extracellular calcium concentration and couples this to intracellular signaling pathways modifying PTH secretion or renal cation handling. Heterozygous loss-of-function mutations cause familial hypocalciuric hypercalcemia (FHH); homozygous mutations cause neonatal severe hyperparathyroidism (NSHPT); gain-of-function mutations cause autosomal dominant hypocalcemia (ADH).","method":"Mutational analysis of CASR gene combined with clinical phenotype/genotype correlation; functional characterization of disease-causing variants","journal":"Human mutation","confidence":"High","confidence_rationale":"Tier 2 / Strong — replicated across multiple labs with genotype-phenotype correlation and functional variant studies","pmids":["11013439"],"is_preprint":false},{"year":2008,"finding":"Tissue-specific deletion of Casr in parathyroid gland or bone caused profound bone defects; deletion in chondrocytes caused embryonic death before E13; inducible chondrocyte-specific deletion between E16-E18 resulted in delayed growth plate development, demonstrating a nonredundant role for CaSR in early embryogenesis and skeletal development.","method":"Conditional/tissue-specific Casr knockout mice (Cre-lox); histological and developmental phenotypic analysis","journal":"Science signaling","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple tissue-specific KO models with defined cellular phenotypes, replicated across tissues","pmids":["18765830"],"is_preprint":false},{"year":2009,"finding":"CaSR defends against hypercalcemia independently of its regulation of PTH secretion: CaSR-null/PTH-null double knockout mice showed increased susceptibility to hypercalcemia and reduced renal Ca2+ clearance compared to PTH-null alone mice, demonstrating a direct role of CaSR in regulating renal Ca2+ handling and stimulating calcitonin secretion during hypercalcemia.","method":"Single and double knockout mouse models (CaSR-/-, PTH-/-, CaSR-/-/PTH-/- double KO); hypercalcemic challenge experiments; serum calcitonin and urinary Ca measurements","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with multiple KO genotypes and multiple hypercalcemic challenges, clear mechanistic separation of PTH-dependent vs. CaSR-dependent effects","pmids":["19797241"],"is_preprint":false},{"year":2013,"finding":"CaSR controls heterotrimeric G-proteins Gq/11, Gi/o, and G12/13 and their downstream signaling consequences. CaSR forms specific signaling scaffolds via peptide recognition sequences in its intracellular C-terminal tail, and interacts with filamin-A and caveolin-1 as scaffold partners. CaSR exhibits high cooperativity for Ca2+o and resistance to desensitization, and mediates both oscillatory and sustained Ca2+i mobilizing responses as well as context-dependent inhibition or elevation of cAMP. Ligand-biased signaling was identified for agonists including Sr2+ and modulators including L-amino acids and cinacalcet.","method":"Pharmacological and signaling pathway analyses; review integrating biochemical signaling data","journal":"Best practice & research. Clinical endocrinology & metabolism","confidence":"Medium","confidence_rationale":"Tier 3 / Strong — well-established signaling pathways synthesized from multiple studies, but this paper is a review without primary experimental data","pmids":["23856262"],"is_preprint":false},{"year":2013,"finding":"The human CASR gene has two promoters (P1 and P2) driving transcription of exons 1A and 1B respectively, with alternative 5'-UTRs splicing to exon 2. Functional elements responsive to 1,25-dihydroxyvitamin D, proinflammatory cytokines, and glial cells missing-2 (GCM2) are present in CASR promoters. The extracellular domain has a bi-lobed Venus Flytrap (VFT) domain with several Ca2+-binding sites, and a nine-cysteines domain that transduces activation to the 7-transmembrane domain.","method":"Genomic cloning, structural analysis, promoter reporter assays","journal":"Best practice & research. Clinical endocrinology & metabolism","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — structural and promoter characterization supported by genomic and functional data from prior studies synthesized in review","pmids":["23856260"],"is_preprint":false},{"year":2000,"finding":"The human CaSR gene has two promoters and two 5'-untranslated exons (1A and 1B); alternative usage of these exons produces multiple CaSR mRNAs. The upstream promoter (driving exon 1A) is specifically reduced in parathyroid adenomas compared to normal glands, while exon 1B expression is unchanged, indicating selective transcriptional silencing of one promoter in parathyroid tumorigenesis.","method":"Genomic library screening, promoter cloning, Northern blot analysis of parathyroid adenoma vs. normal tissue","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — direct cloning and Northern blot with comparisons between tumor and normal tissue, multiple methods in a primary experimental study","pmids":["10713061"],"is_preprint":false},{"year":2008,"finding":"CaSR activation in the thick ascending limb (TAL) inhibits cellular Ca2+ absorption induced by PTH as well as passive paracellular Ca2+ transport; CaSR also regulates the apical Na+:K+:2Cl- co-transporter (NKCC2) and disruption of CaSR function results in Bartter syndrome.","method":"Genetic and pharmacological disruption in renal tubule models; review of molecular physiology","journal":"Pflugers Archiv : European journal of physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — synthesis of multiple mechanistic studies on TAL CaSR function, supported by genetic disease models (Bartter syndrome)","pmids":["18982348"],"is_preprint":false},{"year":2012,"finding":"CaSR interacts with filamin-A and caveolin-1 as scaffold partners that organize CaSR signaling compartmentally. CaSR links to various heterotrimeric and small molecular weight G proteins to regulate intracellular second messengers, lipid kinases, various protein kinases, and transcription factors.","method":"Co-immunoprecipitation and signaling pathway analysis; review of established binding partners","journal":"Advances in experimental medicine and biology","confidence":"Medium","confidence_rationale":"Tier 3 / Strong — scaffold interactions replicated across multiple papers cited in this review","pmids":["22453940"],"is_preprint":false},{"year":2013,"finding":"CaSR activation in intestinal myofibroblasts stimulates secretion of Wnt5a, which engages its receptor Ror2 on overlying epithelial cells to promote differentiation and reduce TNFR1 expression. CaSR activators also inhibit Cl- secretion and stimulate Na+ absorption. Colonic CaSR KO mice show increased proliferation with increased Wnt/β-catenin signaling, demonstrating that CaSR negatively modulates colonic epithelial growth.","method":"Transgenic and global CaSR knockout mice; cell culture models; paracrine signaling assays","journal":"Best practice & research. Clinical endocrinology & metabolism","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CaSR KO mouse phenotype plus cell culture epistasis establishing Wnt5a/Ror2 pathway","pmids":["23856267"],"is_preprint":false},{"year":2014,"finding":"Extracellular calcium induces rat bone marrow mesenchymal stromal cell migration, proliferation, and osteoblastic differentiation (upregulation of ALP, bone sialoprotein, collagen Ia1, osteocalcin) in a CaSR-dependent manner; CaSR blockage inhibited all these cellular responses to high [Ca2+]o.","method":"CaSR pharmacological blockade; RT-PCR; immunofluorescence; functional ALP activity and mineralization assays in rBMSCs","journal":"Acta biomaterialia","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (gene expression, protein, functional assay) with pharmacological CaSR inhibition, single lab","pmids":["24525034"],"is_preprint":false},{"year":2014,"finding":"CaSR forms a heteromeric complex with the inhibitory GABA-B receptor 1 (GABABR1) in hippocampal neurons. Ischemia causes CaSR overexpression and GABABR1 downregulation. Genetic ablation of Casr or CaSR antagonism provided neuroprotection partly by restoring GABABR1 expression; concurrent ablation of Gabbr1 blocked this neuroprotection, demonstrating functional antagonism between the two receptors.","method":"Neuron-specific Casr and Gabbr1 knockout mice; forebrain ischemia model; pharmacological CaSR inhibition (calcilytics) ± GABABR1 agonist (baclofen); behavioral memory assessment","journal":"Annals of clinical and translational neurology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO epistasis with multiple genotypes plus pharmacological validation, double KO demonstrates mechanistic dependence","pmids":["25540800"],"is_preprint":false},{"year":2013,"finding":"CaSR activates signaling through PLCγ in osteoblasts to promote bone formation; inflammatory cytokines upregulate CaSR expression through NF-κB/p65 and JAK/Stat3 pathways in osteoblasts, and CaSR-PLCγ signaling mediates pathological new bone formation in ankylosing spondylitis.","method":"In vitro CaSR activation/inhibition in osteoblasts; animal models of ankylosing spondylitis; CaSR antagonist treatment; in vivo bone formation assays","journal":"EMBO molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro and in vivo mechanistic studies with pathway identification and pharmacological rescue, single lab","pmids":["33259138"],"is_preprint":false},{"year":2018,"finding":"CaSR signaling in the renal collecting duct reduces AQP2 abundance via two mechanisms: (1) activation of p38-MAPK leading to AQP2 phosphorylation at Ser261, ubiquitination, and proteasomal degradation; and (2) upregulation of AQP2-targeting miRNA-137. CaSR inhibition with calcilytic NPS2143 reversed these effects in pendrin/NaCl cotransporter double-KO mice.","method":"Pendrin/NaCl cotransporter double-KO mouse model; calcilytic treatment; Western blot for AQP2 phosphorylation and ubiquitination; miRNA quantification","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — two orthogonal mechanisms identified (miRNA and p38-MAPK/ubiquitination), genetic KO model plus pharmacological rescue with calcilytic","pmids":["29212817"],"is_preprint":false},{"year":2015,"finding":"CaSR-dependent ERK1/2 activation promotes axon growth in embryonic sympathetic neurons. The region between alanine 877 and glycine 907 of the CaSR cytoplasmic tail is required for ERK1/2 activation and axon growth promotion, distinct from the high-affinity filamin-A binding site.","method":"Cultured embryonic sympathetic neurons; CaSR deletion mutants; pharmacological ERK inhibition; axon growth measurement","journal":"Neuroscience letters","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — deletion mutagenesis identifying functional domain plus pharmacological inhibition, single lab","pmids":["26200251"],"is_preprint":false},{"year":2019,"finding":"Homer1 scaffolding protein associates with CaSR in primary human osteoblasts (confirmed by co-immunoprecipitation). The CaSR-Homer1 complex, whose formation increases in response to extracellular Ca2+, binds mTORC2, which phosphorylates and activates AKT at Ser473. Both CaSR and Homer1 are required for extracellular Ca2+-stimulated AKT phosphorylation, inhibition of apoptosis, and AKT-dependent β-catenin stabilization and osteoblast differentiation. Co-transfection of both Homer1c and CaSR (but neither alone) in HEK-293 cells recapitulated Ca2+-sensitive AKT-Ser473 phosphorylation.","method":"Co-immunoprecipitation in primary human osteoblasts; siRNA knockdown; HEK-293 co-transfection reconstitution; Western blot for AKT phosphorylation and β-catenin","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — reciprocal Co-IP, siRNA loss-of-function, reconstitution in HEK-293 cells, multiple orthogonal methods in single study","pmids":["31527082"],"is_preprint":false},{"year":2012,"finding":"CaSR plasma membrane trafficking is driven by CaSR signaling itself: agonist-driven anterograde CaSR trafficking establishes a new steady-state plasma membrane level. FHH/NSHPT loss-of-function mutations impair both plasma membrane targeting and Ca2+ signaling. Wild-type CaSR rescues mutant trafficking by providing sufficient intracellular Ca2+ signaling; heterodimerization alone (with intracellular Ca2+ oscillations only) was insufficient for rescue.","method":"Chimeric CaSR constructs for explicit plasma membrane tracking; simultaneous dynamic monitoring of plasma membrane CaSR levels and intracellular Ca2+; co-expression of WT and mutant CaSRs","journal":"Molecular endocrinology (Baltimore, Md.)","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal approaches (chimeric reporter, Ca2+ imaging, co-expression rescue experiments) in single rigorous study","pmids":["23077345"],"is_preprint":false},{"year":2019,"finding":"Biomechanical stress (fluid flow shear stress) increases CaSR expression and causes CaSR localization to the endoplasmic reticulum (ER) in chondrocytes, leading to Ca2+ loading and accelerated chondrocyte terminal differentiation. Chondrocyte-specific Casr knockout prevented UAC-induced acceleration of terminal differentiation and matrix degradation in TMJ cartilage; this was replicated pharmacologically with CaSR antagonist NPS2143.","method":"ATDC5 cell shear stress model; chondrocyte-specific Casr conditional KO mice; rat UAC osteoarthritis model; CaSR antagonist injection; CaSR knockdown; ER Ca2+ depletion experiments","journal":"Journal of bone and mineral research","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO plus pharmacological rescue plus in vitro mechanism, multiple orthogonal approaches across cell and animal models","pmids":["30496623"],"is_preprint":false},{"year":2016,"finding":"Filamin A (FLNA) co-localizes with CaSR in parathyroid adenoma-derived cells and is reduced in parathyroid tumors. FLNA silencing in HEK293 cells reduced CaSR mRNA levels, total and membrane-associated CaSR protein, and CaSR-induced ERK phosphorylation. FLNA expression positively correlates with CaSR expression in parathyroid adenomas.","method":"Co-immunoprecipitation/co-localization; FLNA siRNA knockdown in HEK293 cells transfected with CaSR variants; Western blot; correlation analysis in 74 parathyroid adenomas","journal":"Journal of molecular endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-localization plus siRNA loss-of-function, single lab with multiple readouts","pmids":["27872158"],"is_preprint":false},{"year":2021,"finding":"The renal CaSR, Klotho, and ADAM10 co-localize on the basolateral membrane of the distal convoluted tubule (DCT). CaSR activation by calcimimetics or HCO3- increases sKlotho levels in WT but not tubule-specific CaSR-/- mice. CaSR activation stimulates Klotho shedding via ADAM10 protease, as shown by ADAM10 inhibitor (GI254023X) and siRNA.","method":"Tubule-specific CaSR KO mice; calcimimetic and alkali treatment; confocal microscopy for CaSR/Klotho/ADAM10 co-localization; ADAM10 inhibitor and siRNA in cultured cells; sKlotho ELISA","journal":"Journal of the American Society of Nephrology : JASN","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO mice plus pharmacological/siRNA inhibition plus co-localization, multiple orthogonal approaches in single study","pmids":["34551996"],"is_preprint":false},{"year":2013,"finding":"CaSR mediates magnesium homeostasis: mice lacking both CaSR and PTH showed greater increases in serum Mg and Ca during Mg loading than PTH-null or WT mice, and CaSR loss abrogated calcitonin secretion in response to Mg loading, demonstrating CaSR's direct role in Mg homeostasis independent of PTH.","method":"PTH-KO and CaSR/PTH double-KO mouse models; Mg loading experiments; serum measurements of Mg, Ca, PTH, calcitonin, 1,25-dihydroxyvitamin D","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with multiple KO genotypes and multiple mineral challenges clearly separating CaSR and PTH effects","pmids":["23360827"],"is_preprint":false},{"year":2015,"finding":"CaSR in intestinal epithelial cells mediates anti-inflammatory effects of L-tryptophan: L-Trp reduced TNF-α-induced IL-8 secretion and inhibited JNK and IκBα phosphorylation via CaSR activation. The CaSR antagonist NPS-2143 abrogated these effects. β-arrestin2 was found to block TNF-α-induced signaling pathways after CaSR activation by L-Trp.","method":"Caco-2 and HT-29 cell lines; CaSR antagonist (NPS-2143) treatment; Western blot for JNK and IκBα phosphorylation; IL-8 ELISA","journal":"Journal of agricultural and food chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological CaSR inhibition with multiple signaling readouts, single lab with two cell lines","pmids":["26551350"],"is_preprint":false},{"year":2021,"finding":"Tryptophan enhances intestinal epithelial barrier integrity and reduces inflammatory responses through the CaSR/Rac1/PLC-γ1 signaling pathway: CaSR activation by tryptophan increases GTP-Rac1 and p-PLC-γ1; Rac1-siRNA, PLC-γ1-siRNA, or CaSR inhibitor blocked tryptophan's protective effects; CaSR overexpression increased cell migration that was reduced by Rac1 or PLC-γ1 silencing.","method":"IPEC-J2 cells; CaSR overexpression and CaSR inhibitor (NPS-2143); Rac1-siRNA and PLC-γ1-siRNA; TEER measurement; FITC-dextran permeability; Western blot","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pathway placement by multiple siRNA KDs plus CaSR OE and inhibitor, single lab","pmids":["34745120"],"is_preprint":false},{"year":2023,"finding":"CaSR activates ERK1/2 in pancreatic α cells via Gq (not Gi) signaling to drive hyperaminoacidemia-induced α cell proliferation. CaSR is also required for mTORC1 activation in α cells. Coactivation of Gq and mTORC1 was sufficient to induce α cell proliferation independent of hyperaminoacidemia.","method":"Mouse islets and glucagon receptor-deficient zebrafish; CaSR inactivation and rescue experiments; Gq vs. Gi signaling dissection; ERK1/2 activation assays; mTORC1 pathway analysis","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — two model organisms, loss-of-function rescue with specific G-protein pathway (Gq vs Gi), mTORC1 mechanistic dissection, multiple orthogonal approaches","pmids":["36646689"],"is_preprint":false},{"year":2019,"finding":"CaSR activates PKCδ which translocates to the ER to induce ER stress responses and ER stress-associated cardiomyocyte apoptosis during ischemia/reperfusion. CaSR activation with GdCl3 increased CaSR, GRP78, Caspase-12, p-JNK, and Caspase-3 expression and increased apoptotic cell ratios; PKCδ inhibitor (rottlerin) reversed these effects.","method":"In vivo rat cardiac I/R model; CaSR activator (GdCl3) and PKCδ inhibitor (rottlerin); Western blot for ER stress markers; apoptosis quantification","journal":"International journal of molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological activation/inhibition with mechanistic pathway dissection in vivo, single lab","pmids":["31257458"],"is_preprint":false},{"year":2014,"finding":"ZnR/GPR39 activity is regulated by the expression and activity of CaSR in prostate and salivary epithelial cells. Co-expression of CaSR and ZnR/GPR39 synergistically enhances Ca2+ responses; CaSR silencing (siRNA or dominant-negative) reduces Zn2+-dependent signaling, while CaSR agonist spermine below threshold enhanced Zn2+-dependent Ca2+ response.","method":"CaSR siRNA silencing; dominant-negative CaSR; GPR39 overexpression in HEK293 cells; Ca2+ imaging; pharmacological CaSR activation","journal":"Journal of cellular physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA, dominant-negative and reconstitution approaches, single lab","pmids":["24264723"],"is_preprint":false},{"year":2020,"finding":"CaSR promoter 2 hypermethylation and increased H3K9me3 are epigenetic mechanisms that silence CaSR expression in sporadic parathyroid adenomas. Treatment with 5-aza-2'deoxycytidine (DNA demethylase) restored CaSR expression in a parathyroid cell line. The GCM2 binding site on CaSR promoter 2 showed maximum CpG methylation.","method":"Bisulphite sequencing; chromatin immunoprecipitation-qPCR; 5-aza-2'deoxycytidine treatment; qPCR and IHC in 40 adenomas vs. 10 controls","journal":"The Journal of clinical endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 2 / Strong — bisulphite sequencing plus ChIP-qPCR plus pharmacological demethylation rescue, multiple orthogonal epigenetic methods in primary tumors","pmids":["32609827"],"is_preprint":false},{"year":2024,"finding":"Upper small intestinal CaSR is required for casein infusion to increase glucose tolerance and GLP-1/GIP secretion (in a PepT1-dependent manner). Ileal CaSR (PepT1-independent) is required to lower feeding and increase glucose tolerance with concurrent PYY and GLP-1 release. High-fat diet decreases ileal CaSR expression and disrupts casein sensing on feeding.","method":"Upper small intestine and ileum casein infusion in male rats; pharmacological CaSR inhibition; measurement of gut hormones (GLP-1, GIP, PYY); glucose tolerance tests; feeding behavior assays","journal":"Nature metabolism","confidence":"High","confidence_rationale":"Tier 2 / Strong — segment-specific pharmacological inhibition with multiple hormone readouts and behavioral endpoints, mechanistic dissection of CaSR vs. PepT1 pathways","pmids":["38167726"],"is_preprint":false},{"year":2019,"finding":"CaSR activation promotes M1 macrophage polarization by coupling to TRPV4 channels via PLA2/CYP450 and PLC/PKC pathways, leading to Ca2+ entry and upregulation of M1-associated cytokines IL-1β and TNFα. CaSR-induced Ca2+ signaling was significantly attenuated in TRPV4 knockout macrophages.","method":"TRPV4 KO mice peritoneal macrophages; pharmacological CaSR and TRPV4 inhibitors; pathway inhibitors (PLA2/CYP450, PLC/PKC); Ca2+ imaging; cytokine measurement","journal":"Acta physiologica (Oxford, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — TRPV4 KO genetic model plus pharmacological pathway dissection, single lab","pmids":["36606511"],"is_preprint":false},{"year":2021,"finding":"CaSR promotes Rab27B expression and activates this secretory GTPase via PI3K, PKA, mTOR, and MADD (a guanine nucleotide exchange factor) in breast cancer cells, leading to secretion of cytokines and chemokines (IL-6, IL-1β, IL-8, IP-10, RANTES). This regulatory mechanism occurred in MDA-MB-231 and MCF-7 but not non-cancerous MCF-10A cells.","method":"CaSR stimulation in breast cancer cell lines; PI3K/PKA/mTOR inhibitors; MADD identification; cytokine secretion assays; Rab27B expression analysis","journal":"Biochimica et biophysica acta. Molecular cell research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple pathway inhibitors plus mechanistic identification of GEF (MADD), single lab","pmids":["33845096"],"is_preprint":false},{"year":2013,"finding":"CaSR expression and function is required for TGFβ receptor expression and cellular responses to TGFβ in human colonic epithelial cells. Knockdown of CaSR abrogated TGFβ-mediated cellular responses and attenuated TGFβ receptor expression; Ca2+ or vitamin D treatment induced CaSR expression with concurrent TGFβ receptor upregulation, but only when CaSR was present.","method":"CaSR shRNA knockdown in CBS cells; Ca2+ and vitamin D treatment; TGFβ receptor expression analysis; TGFβ response assays","journal":"Cell calcium","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA loss-of-function plus ligand stimulation with mechanistic pathway placement, single lab","pmids":["23639611"],"is_preprint":false},{"year":2016,"finding":"CaSR in esophageal epithelial cells (HET-1A line) mediates Ca2+ stimulation of ERK1/2 activation, intracellular Ca2+ mobilization via PI-PLC (blocked by U73122), and IL-8 secretion. siRNA knockdown of CaSR attenuated these Ca2+-induced responses while responses to acetylcholine remained sustained, confirming CaSR-specific signal transduction.","method":"CaSR siRNA transfection in HET-1A cells; PI-PLC inhibitor U73122; ERK Western blot; intracellular Ca2+ microfluorometry (Fluo-4); IL-8 ELISA","journal":"American journal of physiology. Gastrointestinal and liver physiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — siRNA-specific knockdown with multiple orthogonal readouts (Ca2+ imaging, kinase activation, cytokine secretion) and pathway inhibitor, single rigorous study","pmids":["17962359"],"is_preprint":false},{"year":2013,"finding":"CaSR signaling in vascular smooth muscle cells (hVSMCs) reduces vascular calcification. Calcimimetics (R-568, AMG 641) promote CaSR protein transport from ER to plasma membrane, increase total and surface CaSR expression, decrease matrix collagen secretion, and reduce mineral deposition by ~90% under pro-mineralizing conditions. These effects required CaSR activation as they were blocked by CaSR siRNA but not scrambled siRNA.","method":"hVSMC culture with calcimimetics; CaSR siRNA vs. scrambled siRNA; flow cytometry for surface CaSR; Alizarin red mineralization assay; qRT-PCR for phenotype markers","journal":"Cardiovascular research","confidence":"High","confidence_rationale":"Tier 2 / Strong — siRNA specificity control, multiple orthogonal methods (flow cytometry, mineralization, gene expression), direct rescue with CaSR knockdown demonstrating mechanistic dependence","pmids":["24217682"],"is_preprint":false}],"current_model":"CaSR is a family C G protein-coupled receptor that functions as the principal extracellular Ca2+ sensor: it couples to Gq/11, Gi/o, and G12/13 to regulate PTH secretion, renal Ca2+/Mg2+ handling, calcitonin release, and AQP2 trafficking (via p38-MAPK/ubiquitination and miRNA-137); it signals through PLC, PKC, ERK, PI3K/AKT, and mTORC2 via scaffold interactions with Homer1, filamin-A, and caveolin-1; it drives tissue-specific outcomes including skeletal development (chondrocyte/osteoblast differentiation via PLCγ and AKT/β-catenin), intestinal hormone secretion and barrier function (via CaSR/Rac1/PLC-γ1), neuroprotection through antagonistic regulation of GABABR1, and regulation of sKlotho shedding via ADAM10 in renal DCT cells; loss-of-function mutations cause FHH/NSHPT and gain-of-function mutations cause autosomal dominant hypocalcemia."},"narrative":{"mechanistic_narrative":"CASR encodes a family C G protein-coupled receptor that serves as the principal sensor of extracellular calcium, coupling small changes in [Ca2+]o through Gq/11, Gi/o, and G12/13 to PTH secretion, renal cation handling, and calcitonin release [PMID:11013439, PMID:23856262]. Its extracellular bi-lobed Venus Flytrap domain binds Ca2+ and transduces activation through a nine-cysteine linker to the seven-transmembrane domain, conferring high cooperativity and ligand-biased responses to agonists such as Sr2+ and modulators including L-amino acids and cinacalcet [PMID:23856262, PMID:23856260]. Beyond regulating PTH, CaSR directly defends against hypercalcemia by stimulating calcitonin secretion and renal Ca2+ clearance, and governs Mg2+ homeostasis, independently of PTH [PMID:19797241, PMID:23360827]; in the renal tubule it inhibits PTH-driven Ca2+ absorption and regulates NKCC2 in the thick ascending limb, suppresses AQP2 via p38-MAPK/ubiquitination and miR-137, and drives ADAM10-mediated shedding of soluble Klotho in the distal convoluted tubule [PMID:18982348, PMID:29212817, PMID:34551996]. Intracellularly, CaSR organizes compartmentalized signaling through scaffold interactions with filamin-A, caveolin-1, and Homer1, the latter recruiting mTORC2 to phosphorylate AKT-Ser473 and stabilize beta-catenin during osteoblast differentiation [PMID:23856262, PMID:22453940, PMID:31527082]; agonist-driven anterograde trafficking sets steady-state plasma-membrane receptor levels, and filamin-A supports CaSR expression and ERK signaling [PMID:23077345, PMID:27872158]. Through these effectors CaSR controls tissue-specific outcomes spanning skeletal and chondrocyte development [PMID:18765830, PMID:30496623], intestinal hormone secretion, barrier integrity, and epithelial growth via Wnt5a/Ror2 and Rac1/PLC-gamma1 [PMID:23856267, PMID:34745120, PMID:38167726], pancreatic alpha-cell proliferation via Gq/ERK and mTORC1 [PMID:36646689], macrophage polarization through TRPV4 [PMID:36606511], and neuroprotection via functional antagonism of GABABR1 [PMID:25540800]. Loss-of-function mutations cause familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism, while gain-of-function mutations cause autosomal dominant hypocalcemia [PMID:11013439]. In sporadic parathyroid adenomas, CaSR is silenced through promoter-2 hypermethylation and H3K9me3 [PMID:32609827].","teleology":[{"year":2000,"claim":"Establishing CaSR as a parathyroid/kidney calcium-sensing GPCR whose dose of function maps to distinct mineral disorders defined its core physiological role.","evidence":"Mutational analysis with genotype-phenotype correlation and functional variant characterization","pmids":["11013439"],"confidence":"High","gaps":["Did not resolve the downstream signaling effectors mediating PTH suppression versus renal handling","Structural basis of activation not defined"]},{"year":2000,"claim":"Identifying dual CASR promoters and showing selective silencing of the upstream promoter in parathyroid adenomas connected receptor transcriptional control to tumorigenesis.","evidence":"Genomic cloning and Northern blot of adenoma versus normal parathyroid tissue","pmids":["10713061"],"confidence":"High","gaps":["Mechanism of promoter silencing not yet identified","Functional consequence on Ca2+ sensing in tumors not measured"]},{"year":2008,"claim":"Tissue-specific knockouts demonstrated nonredundant CaSR roles in early embryogenesis and skeletal development beyond mineral homeostasis.","evidence":"Conditional Cre-lox Casr knockouts in parathyroid, bone, and chondrocytes with developmental phenotyping","pmids":["18765830"],"confidence":"High","gaps":["Signaling effectors driving chondrocyte/osteoblast phenotypes not defined here","Embryonic lethality mechanism unresolved"]},{"year":2009,"claim":"Genetic epistasis with PTH-null mice separated CaSR's PTH-independent defense against hypercalcemia via renal clearance and calcitonin from its PTH-regulating role.","evidence":"CaSR/PTH single and double knockout mice with hypercalcemic challenge and serum/urinary measurements","pmids":["19797241"],"confidence":"High","gaps":["Renal transport molecules mediating CaSR-dependent Ca2+ clearance not identified","Calcitonin cell signaling pathway not dissected"]},{"year":2013,"claim":"Genetic dissection extended CaSR's PTH-independent role to magnesium homeostasis and Mg-stimulated calcitonin secretion.","evidence":"PTH-KO and CaSR/PTH double-KO mice with Mg loading and serum measurements","pmids":["23360827"],"confidence":"High","gaps":["Renal Mg transporters downstream of CaSR not specified","Tissue site of Mg sensing not localized"]},{"year":2012,"claim":"Defining agonist-driven anterograde trafficking and demonstrating that WT receptor rescues mutant trafficking via shared intracellular Ca2+ signaling clarified how membrane receptor levels are set and how dominant mutations behave.","evidence":"Chimeric CaSR reporters with simultaneous membrane and Ca2+ imaging and WT/mutant co-expression rescue","pmids":["23077345"],"confidence":"High","gaps":["Trafficking machinery and adaptors not identified","Generality across all FHH/NSHPT mutant classes untested"]},{"year":2012,"claim":"Cataloguing filamin-A and caveolin-1 as scaffold partners established that CaSR signaling is compartmentally organized.","evidence":"Co-immunoprecipitation and signaling analysis synthesized in review","pmids":["22453940"],"confidence":"Medium","gaps":["Review without primary data","Stoichiometry and structural basis of scaffolds not defined"]},{"year":2013,"claim":"Synthesis of pharmacology defined CaSR's tripartite G-protein coupling, biased agonism, resistance to desensitization, and VFT/cysteine-rich/7TM domain architecture, framing the receptor as a multi-output signaling hub.","evidence":"Review integrating signaling and structural/promoter data","pmids":["23856262","23856260"],"confidence":"Medium","gaps":["Reviews without new primary data","Quantitative bias factors and structural mechanism of biased signaling not resolved"]},{"year":2013,"claim":"Multiple tissue studies placed CaSR upstream of distinct effector pathways: TAL Ca2+ transport/NKCC2, intestinal Wnt5a/Ror2 control of epithelial growth, TGFbeta receptor expression, and osteoblast PLC-gamma-driven bone formation.","evidence":"Renal tubule disruption, global/colonic CaSR KO mice with cell culture epistasis, shRNA knockdown, and osteoblast/ankylosing spondylitis models","pmids":["18982348","23856267","23639611","33259138"],"confidence":"Medium","gaps":["Direct physical links between CaSR and these effectors not all established","Mostly single-lab pathway placements"]},{"year":2014,"claim":"Pharmacological and reconstitution studies tied extracellular Ca2+/CaSR signaling to mesenchymal/osteoblast differentiation and to cross-regulation of the zinc receptor ZnR/GPR39.","evidence":"CaSR blockade in rBMSCs with differentiation assays; CaSR siRNA/dominant-negative and GPR39 co-expression in HEK293 with Ca2+ imaging","pmids":["24525034","24264723"],"confidence":"Medium","gaps":["Direct receptor cross-talk mechanism with GPR39 not structurally defined","In vivo relevance of GPR39 interplay not tested"]},{"year":2014,"claim":"Genetic and pharmacological epistasis revealed a heteromeric CaSR-GABABR1 complex in neurons in which CaSR antagonism is neuroprotective by restoring GABABR1, establishing functional receptor antagonism in ischemia.","evidence":"Neuron-specific Casr and Gabbr1 KO mice, forebrain ischemia, calcilytics +/- baclofen, behavioral testing","pmids":["25540800"],"confidence":"High","gaps":["Molecular interface of the heteromer not mapped","Signaling consequences of complex formation not fully resolved"]},{"year":2015,"claim":"Domain-mapping and ligand studies localized CaSR's ERK1/2-driving region to residues 877-907 (distinct from filamin-A binding) and demonstrated CaSR/ERK-mediated anti-inflammatory effects of L-tryptophan via beta-arrestin2.","evidence":"CaSR deletion mutants in sympathetic neurons with ERK inhibition; Caco-2/HT-29 cells with NPS-2143 and signaling readouts","pmids":["26200251","26551350"],"confidence":"Medium","gaps":["Direct effector binding to the 877-907 region not identified","beta-arrestin2 recruitment mechanism not structurally defined"]},{"year":2016,"claim":"Filamin-A was shown to be required for CaSR expression, membrane localization, and ERK signaling, and CaSR-specific signaling in esophageal epithelium (ERK, PI-PLC Ca2+ mobilization, IL-8) was established by knockdown specificity.","evidence":"FLNA siRNA in HEK293 with adenoma correlation; CaSR siRNA in HET-1A cells with U73122 and multiple readouts","pmids":["27872158","17962359"],"confidence":"Medium","gaps":["Mechanism by which FLNA stabilizes CaSR transcript/protein not defined","In vivo relevance of esophageal CaSR signaling untested"]},{"year":2018,"claim":"Renal collecting-duct studies identified two parallel CaSR mechanisms suppressing AQP2 (p38-MAPK/Ser261 phosphorylation/ubiquitination and miR-137), linking CaSR to water handling.","evidence":"Pendrin/NCC double-KO mice with calcilytic NPS2143, AQP2 Western blot, and miRNA quantification","pmids":["29212817"],"confidence":"High","gaps":["Upstream coupling of CaSR to p38 and miR-137 induction not detailed","Relative contribution of the two arms not quantified"]},{"year":2019,"claim":"The Homer1 scaffold was shown to bridge CaSR to mTORC2-dependent AKT-Ser473 phosphorylation, beta-catenin stabilization, and osteoblast differentiation, providing a reconstituted mechanistic chain.","evidence":"Reciprocal Co-IP in human osteoblasts, siRNA loss-of-function, and HEK-293 Homer1c/CaSR co-transfection reconstitution","pmids":["31527082"],"confidence":"High","gaps":["Structural basis of the CaSR-Homer1-mTORC2 assembly not solved","In vivo bone phenotype of disrupting this axis not tested"]},{"year":2019,"claim":"Additional effector branches were defined: biomechanical-stress-induced ER localization driving chondrocyte terminal differentiation, PKCdelta/ER-stress cardiomyocyte apoptosis, and TRPV4-coupled M1 macrophage polarization.","evidence":"Chondrocyte-specific Casr KO with shear-stress and OA models; rat cardiac I/R with rottlerin; TRPV4 KO macrophages with pathway inhibitors","pmids":["30496623","31257458","36606511"],"confidence":"Medium","gaps":["Mechanism of CaSR relocalization to ER not defined","Direct CaSR-TRPV4 coupling versus indirect lipid signaling not fully separated"]},{"year":2020,"claim":"Epigenetic profiling established promoter-2 hypermethylation and H3K9me3 as mechanisms silencing CaSR in sporadic parathyroid adenomas, with demethylase rescue restoring expression.","evidence":"Bisulphite sequencing, ChIP-qPCR, and 5-aza-2'deoxycytidine treatment in adenomas and a parathyroid cell line","pmids":["32609827"],"confidence":"High","gaps":["Trigger initiating CaSR promoter methylation unknown","Whether silencing is cause or consequence of tumorigenesis not resolved"]},{"year":2021,"claim":"CaSR was placed in renal sKlotho regulation and in cancer secretory signaling: it drives ADAM10-mediated Klotho shedding in the DCT and Rab27B-dependent cytokine secretion in breast cancer cells.","evidence":"Tubule-specific CaSR KO mice with ADAM10 inhibitor/siRNA and co-localization; breast cancer lines with PI3K/PKA/mTOR inhibitors and MADD identification","pmids":["34551996","33845096"],"confidence":"High","gaps":["How CaSR activates ADAM10 mechanistically not defined","Cancer-cell-selectivity of the Rab27B pathway not mechanistically explained"]},{"year":2021,"claim":"CaSR/Rac1/PLC-gamma1 signaling was defined as the pathway by which tryptophan enhances intestinal epithelial barrier integrity and migration.","evidence":"IPEC-J2 cells with CaSR overexpression/inhibitor and Rac1/PLC-gamma1 siRNA, TEER and permeability assays","pmids":["34745120"],"confidence":"Medium","gaps":["Direct CaSR-Rac1 coupling intermediary (GEF) not identified","Single cell-line, in vivo validation lacking"]},{"year":2023,"claim":"G-protein-selective dissection showed CaSR drives pancreatic alpha-cell proliferation via Gq/ERK and mTORC1 during hyperaminoacidemia, with Gq+mTORC1 coactivation sufficient.","evidence":"Mouse islets and glucagon-receptor-deficient zebrafish with CaSR loss/rescue and Gq-versus-Gi dissection","pmids":["36646689"],"confidence":"High","gaps":["How CaSR selectively engages Gq over Gi in alpha cells not explained","Link between Gq/ERK and mTORC1 activation not fully mapped"]},{"year":2024,"claim":"Segment-specific intestinal studies defined CaSR as a casein/amino-acid sensor controlling incretin and satiety hormone release and glucose tolerance, with high-fat diet impairing ileal CaSR sensing.","evidence":"Upper-intestine and ileum casein infusion in rats with CaSR inhibition, gut hormone measurements, and feeding/glucose-tolerance assays","pmids":["38167726"],"confidence":"High","gaps":["Enteroendocrine cell-intrinsic signaling downstream of CaSR not dissected","Mechanism of HFD-induced CaSR downregulation unknown"]},{"year":null,"claim":"A unified structural and quantitative model of how a single calcium-sensing receptor selects among Gq/11, Gi/o, G12/13, and arrestin outputs and among distinct scaffolds to produce tissue-specific outcomes remains unresolved.","evidence":"No single discovery in the corpus integrates biased coupling, scaffold selection, and tissue context mechanistically","pmids":[],"confidence":"Low","gaps":["No structural model linking ligand bias to G-protein/scaffold selection","Tissue-specific determinants of effector choice not defined","In vivo relevance of many single-lab effector pathways untested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[0,3,4]},{"term_id":"GO:0140299","term_label":"molecular sensor activity","supporting_discovery_ids":[0,3,4,26]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[7,14,17]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,15,31]},{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[16,23,31]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[3,14,22]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[2,6,19]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[1,8,16]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[0,6,25]}],"complexes":["CaSR-GABABR1 heteromer","CaSR-Homer1-mTORC2 complex"],"partners":["FLNA","CAV1","HOMER1","GABBR1","GPR39","TRPV4","ADAM10"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P41180","full_name":"Extracellular calcium-sensing receptor","aliases":["Parathyroid cell calcium-sensing receptor 1","PCaR1"],"length_aa":1078,"mass_kda":120.7,"function":"G-protein-coupled receptor that senses changes in the extracellular concentration of calcium ions and plays a key role in maintaining calcium homeostasis (PubMed:17555508, PubMed:19789209, PubMed:21566075, PubMed:22114145, PubMed:22789683, PubMed:23966241, PubMed:25104082, PubMed:25292184, PubMed:25766501, PubMed:26386835, PubMed:32817431, PubMed:33603117, PubMed:34194040, PubMed:34467854, PubMed:7759551, PubMed:8636323, PubMed:8702647, PubMed:8878438). Senses fluctuations in the circulating calcium concentration: activated by elevated circulating calcium, leading to decreased parathyroid hormone (PTH) secretion in parathyroid glands (By similarity). In kidneys, acts as a key regulator of renal tubular calcium resorption (By similarity). Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G-proteins) and modulates the activity of downstream effectors (PubMed:38632411). CASR is coupled with different G(q)/G(11), G(i)/G(o)- or G(s)-classes of G-proteins depending on the context (PubMed:38632411). In the parathyroid and kidney, CASR signals through G(q)/G(11) and G(i)/G(o) G-proteins: G(q)/G(11) coupling activates phospholipase C-beta, releasing diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) second messengers, while G(i)/G(o) coupling mediates inhibition of adenylate cyclase activity (PubMed:38632411, PubMed:7759551). The G-protein-coupled receptor activity is activated by a co-agonist mechanism: aromatic amino acids, such as Trp or Phe, act concertedly with divalent cations, such as calcium or magnesium, to achieve full receptor activation (PubMed:27386547, PubMed:27434672, PubMed:32817431, PubMed:33603117, PubMed:34194040). Acts as an activator of the NLRP3 inflammasome via G(i)/G(o)-mediated signaling: down-regulation of cyclic AMP (cAMP) relieving NLRP3 inhibition by cAMP (PubMed:32843625). Acts as a regulator of proton-sensing receptor GPR68 in a seesaw manner: CASR-mediated signaling inhibits GPR68 signaling in response to extracellular calcium, while GPR68 inhibits CASR in presence of extracellular protons (By similarity)","subcellular_location":"Cell membrane","url":"https://www.uniprot.org/uniprotkb/P41180/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CASR","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CASR","total_profiled":1310},"omim":[{"mim_id":"617343","title":"HYPERPARATHYROIDISM 4; HRPT4","url":"https://www.omim.org/entry/617343"},{"mim_id":"616884","title":"UNC79 HOMOLOG, NALCN CHANNEL COMPLEX SUBUNIT; UNC79","url":"https://www.omim.org/entry/616884"},{"mim_id":"615361","title":"HYPOCALCEMIA, AUTOSOMAL DOMINANT 2; HYPOC2","url":"https://www.omim.org/entry/615361"},{"mim_id":"613572","title":"G PROTEIN-COUPLED RECEPTOR, FAMILY C, GROUP 6, MEMBER A; GPRC6A","url":"https://www.omim.org/entry/613572"},{"mim_id":"612899","title":"EPILEPSY, IDIOPATHIC GENERALIZED, SUSCEPTIBILITY TO, 8; EIG8","url":"https://www.omim.org/entry/612899"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"parathyroid gland","ntpm":615.6}],"url":"https://www.proteinatlas.org/search/CASR"},"hgnc":{"alias_symbol":["FHH","NSHPT","GPRC2A"],"prev_symbol":["HHC","HHC1"]},"alphafold":{"accession":"P41180","domains":[{"cath_id":"3.40.50.2300","chopping":"19-46_58-189_330-362_393-479","consensus_level":"medium","plddt":88.376,"start":19,"end":479},{"cath_id":"3.40.50.2300","chopping":"191-327_487-528","consensus_level":"medium","plddt":92.1669,"start":191,"end":528},{"cath_id":"-","chopping":"551-601","consensus_level":"high","plddt":88.7827,"start":551,"end":601},{"cath_id":"1.20.1070.10","chopping":"612-709_716-875","consensus_level":"medium","plddt":86.1783,"start":612,"end":875}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P41180","model_url":"https://alphafold.ebi.ac.uk/files/AF-P41180-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P41180-F1-predicted_aligned_error_v6.png","plddt_mean":75.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CASR","jax_strain_url":"https://www.jax.org/strain/search?query=CASR"},"sequence":{"accession":"P41180","fasta_url":"https://rest.uniprot.org/uniprotkb/P41180.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P41180/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P41180"}},"corpus_meta":[{"pmid":"18765830","id":"PMC_18765830","title":"The extracellular calcium-sensing receptor (CaSR) is a critical modulator of skeletal development.","date":"2008","source":"Science signaling","url":"https://pubmed.ncbi.nlm.nih.gov/18765830","citation_count":212,"is_preprint":false},{"pmid":"11013439","id":"PMC_11013439","title":"Mutations of the calcium-sensing receptor (CASR) in familial hypocalciuric hypercalcemia, neonatal severe hyperparathyroidism, and autosomal dominant hypocalcemia.","date":"2000","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/11013439","citation_count":206,"is_preprint":false},{"pmid":"23856262","id":"PMC_23856262","title":"Calcium-sensing receptor (CaSR): pharmacological properties and signaling pathways.","date":"2013","source":"Best practice & research. 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Heterozygous loss-of-function mutations cause familial hypocalciuric hypercalcemia (FHH); homozygous mutations cause neonatal severe hyperparathyroidism (NSHPT); gain-of-function mutations cause autosomal dominant hypocalcemia (ADH).\",\n      \"method\": \"Mutational analysis of CASR gene combined with clinical phenotype/genotype correlation; functional characterization of disease-causing variants\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — replicated across multiple labs with genotype-phenotype correlation and functional variant studies\",\n      \"pmids\": [\"11013439\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Tissue-specific deletion of Casr in parathyroid gland or bone caused profound bone defects; deletion in chondrocytes caused embryonic death before E13; inducible chondrocyte-specific deletion between E16-E18 resulted in delayed growth plate development, demonstrating a nonredundant role for CaSR in early embryogenesis and skeletal development.\",\n      \"method\": \"Conditional/tissue-specific Casr knockout mice (Cre-lox); histological and developmental phenotypic analysis\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple tissue-specific KO models with defined cellular phenotypes, replicated across tissues\",\n      \"pmids\": [\"18765830\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"CaSR defends against hypercalcemia independently of its regulation of PTH secretion: CaSR-null/PTH-null double knockout mice showed increased susceptibility to hypercalcemia and reduced renal Ca2+ clearance compared to PTH-null alone mice, demonstrating a direct role of CaSR in regulating renal Ca2+ handling and stimulating calcitonin secretion during hypercalcemia.\",\n      \"method\": \"Single and double knockout mouse models (CaSR-/-, PTH-/-, CaSR-/-/PTH-/- double KO); hypercalcemic challenge experiments; serum calcitonin and urinary Ca measurements\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with multiple KO genotypes and multiple hypercalcemic challenges, clear mechanistic separation of PTH-dependent vs. CaSR-dependent effects\",\n      \"pmids\": [\"19797241\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR controls heterotrimeric G-proteins Gq/11, Gi/o, and G12/13 and their downstream signaling consequences. CaSR forms specific signaling scaffolds via peptide recognition sequences in its intracellular C-terminal tail, and interacts with filamin-A and caveolin-1 as scaffold partners. CaSR exhibits high cooperativity for Ca2+o and resistance to desensitization, and mediates both oscillatory and sustained Ca2+i mobilizing responses as well as context-dependent inhibition or elevation of cAMP. Ligand-biased signaling was identified for agonists including Sr2+ and modulators including L-amino acids and cinacalcet.\",\n      \"method\": \"Pharmacological and signaling pathway analyses; review integrating biochemical signaling data\",\n      \"journal\": \"Best practice & research. Clinical endocrinology & metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Strong — well-established signaling pathways synthesized from multiple studies, but this paper is a review without primary experimental data\",\n      \"pmids\": [\"23856262\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The human CASR gene has two promoters (P1 and P2) driving transcription of exons 1A and 1B respectively, with alternative 5'-UTRs splicing to exon 2. Functional elements responsive to 1,25-dihydroxyvitamin D, proinflammatory cytokines, and glial cells missing-2 (GCM2) are present in CASR promoters. The extracellular domain has a bi-lobed Venus Flytrap (VFT) domain with several Ca2+-binding sites, and a nine-cysteines domain that transduces activation to the 7-transmembrane domain.\",\n      \"method\": \"Genomic cloning, structural analysis, promoter reporter assays\",\n      \"journal\": \"Best practice & research. Clinical endocrinology & metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — structural and promoter characterization supported by genomic and functional data from prior studies synthesized in review\",\n      \"pmids\": [\"23856260\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"The human CaSR gene has two promoters and two 5'-untranslated exons (1A and 1B); alternative usage of these exons produces multiple CaSR mRNAs. The upstream promoter (driving exon 1A) is specifically reduced in parathyroid adenomas compared to normal glands, while exon 1B expression is unchanged, indicating selective transcriptional silencing of one promoter in parathyroid tumorigenesis.\",\n      \"method\": \"Genomic library screening, promoter cloning, Northern blot analysis of parathyroid adenoma vs. normal tissue\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct cloning and Northern blot with comparisons between tumor and normal tissue, multiple methods in a primary experimental study\",\n      \"pmids\": [\"10713061\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"CaSR activation in the thick ascending limb (TAL) inhibits cellular Ca2+ absorption induced by PTH as well as passive paracellular Ca2+ transport; CaSR also regulates the apical Na+:K+:2Cl- co-transporter (NKCC2) and disruption of CaSR function results in Bartter syndrome.\",\n      \"method\": \"Genetic and pharmacological disruption in renal tubule models; review of molecular physiology\",\n      \"journal\": \"Pflugers Archiv : European journal of physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — synthesis of multiple mechanistic studies on TAL CaSR function, supported by genetic disease models (Bartter syndrome)\",\n      \"pmids\": [\"18982348\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"CaSR interacts with filamin-A and caveolin-1 as scaffold partners that organize CaSR signaling compartmentally. CaSR links to various heterotrimeric and small molecular weight G proteins to regulate intracellular second messengers, lipid kinases, various protein kinases, and transcription factors.\",\n      \"method\": \"Co-immunoprecipitation and signaling pathway analysis; review of established binding partners\",\n      \"journal\": \"Advances in experimental medicine and biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Strong — scaffold interactions replicated across multiple papers cited in this review\",\n      \"pmids\": [\"22453940\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR activation in intestinal myofibroblasts stimulates secretion of Wnt5a, which engages its receptor Ror2 on overlying epithelial cells to promote differentiation and reduce TNFR1 expression. CaSR activators also inhibit Cl- secretion and stimulate Na+ absorption. Colonic CaSR KO mice show increased proliferation with increased Wnt/β-catenin signaling, demonstrating that CaSR negatively modulates colonic epithelial growth.\",\n      \"method\": \"Transgenic and global CaSR knockout mice; cell culture models; paracrine signaling assays\",\n      \"journal\": \"Best practice & research. Clinical endocrinology & metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CaSR KO mouse phenotype plus cell culture epistasis establishing Wnt5a/Ror2 pathway\",\n      \"pmids\": [\"23856267\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Extracellular calcium induces rat bone marrow mesenchymal stromal cell migration, proliferation, and osteoblastic differentiation (upregulation of ALP, bone sialoprotein, collagen Ia1, osteocalcin) in a CaSR-dependent manner; CaSR blockage inhibited all these cellular responses to high [Ca2+]o.\",\n      \"method\": \"CaSR pharmacological blockade; RT-PCR; immunofluorescence; functional ALP activity and mineralization assays in rBMSCs\",\n      \"journal\": \"Acta biomaterialia\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (gene expression, protein, functional assay) with pharmacological CaSR inhibition, single lab\",\n      \"pmids\": [\"24525034\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CaSR forms a heteromeric complex with the inhibitory GABA-B receptor 1 (GABABR1) in hippocampal neurons. Ischemia causes CaSR overexpression and GABABR1 downregulation. Genetic ablation of Casr or CaSR antagonism provided neuroprotection partly by restoring GABABR1 expression; concurrent ablation of Gabbr1 blocked this neuroprotection, demonstrating functional antagonism between the two receptors.\",\n      \"method\": \"Neuron-specific Casr and Gabbr1 knockout mice; forebrain ischemia model; pharmacological CaSR inhibition (calcilytics) ± GABABR1 agonist (baclofen); behavioral memory assessment\",\n      \"journal\": \"Annals of clinical and translational neurology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO epistasis with multiple genotypes plus pharmacological validation, double KO demonstrates mechanistic dependence\",\n      \"pmids\": [\"25540800\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR activates signaling through PLCγ in osteoblasts to promote bone formation; inflammatory cytokines upregulate CaSR expression through NF-κB/p65 and JAK/Stat3 pathways in osteoblasts, and CaSR-PLCγ signaling mediates pathological new bone formation in ankylosing spondylitis.\",\n      \"method\": \"In vitro CaSR activation/inhibition in osteoblasts; animal models of ankylosing spondylitis; CaSR antagonist treatment; in vivo bone formation assays\",\n      \"journal\": \"EMBO molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro and in vivo mechanistic studies with pathway identification and pharmacological rescue, single lab\",\n      \"pmids\": [\"33259138\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"CaSR signaling in the renal collecting duct reduces AQP2 abundance via two mechanisms: (1) activation of p38-MAPK leading to AQP2 phosphorylation at Ser261, ubiquitination, and proteasomal degradation; and (2) upregulation of AQP2-targeting miRNA-137. CaSR inhibition with calcilytic NPS2143 reversed these effects in pendrin/NaCl cotransporter double-KO mice.\",\n      \"method\": \"Pendrin/NaCl cotransporter double-KO mouse model; calcilytic treatment; Western blot for AQP2 phosphorylation and ubiquitination; miRNA quantification\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two orthogonal mechanisms identified (miRNA and p38-MAPK/ubiquitination), genetic KO model plus pharmacological rescue with calcilytic\",\n      \"pmids\": [\"29212817\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"CaSR-dependent ERK1/2 activation promotes axon growth in embryonic sympathetic neurons. The region between alanine 877 and glycine 907 of the CaSR cytoplasmic tail is required for ERK1/2 activation and axon growth promotion, distinct from the high-affinity filamin-A binding site.\",\n      \"method\": \"Cultured embryonic sympathetic neurons; CaSR deletion mutants; pharmacological ERK inhibition; axon growth measurement\",\n      \"journal\": \"Neuroscience letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — deletion mutagenesis identifying functional domain plus pharmacological inhibition, single lab\",\n      \"pmids\": [\"26200251\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Homer1 scaffolding protein associates with CaSR in primary human osteoblasts (confirmed by co-immunoprecipitation). The CaSR-Homer1 complex, whose formation increases in response to extracellular Ca2+, binds mTORC2, which phosphorylates and activates AKT at Ser473. Both CaSR and Homer1 are required for extracellular Ca2+-stimulated AKT phosphorylation, inhibition of apoptosis, and AKT-dependent β-catenin stabilization and osteoblast differentiation. Co-transfection of both Homer1c and CaSR (but neither alone) in HEK-293 cells recapitulated Ca2+-sensitive AKT-Ser473 phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation in primary human osteoblasts; siRNA knockdown; HEK-293 co-transfection reconstitution; Western blot for AKT phosphorylation and β-catenin\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — reciprocal Co-IP, siRNA loss-of-function, reconstitution in HEK-293 cells, multiple orthogonal methods in single study\",\n      \"pmids\": [\"31527082\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"CaSR plasma membrane trafficking is driven by CaSR signaling itself: agonist-driven anterograde CaSR trafficking establishes a new steady-state plasma membrane level. FHH/NSHPT loss-of-function mutations impair both plasma membrane targeting and Ca2+ signaling. Wild-type CaSR rescues mutant trafficking by providing sufficient intracellular Ca2+ signaling; heterodimerization alone (with intracellular Ca2+ oscillations only) was insufficient for rescue.\",\n      \"method\": \"Chimeric CaSR constructs for explicit plasma membrane tracking; simultaneous dynamic monitoring of plasma membrane CaSR levels and intracellular Ca2+; co-expression of WT and mutant CaSRs\",\n      \"journal\": \"Molecular endocrinology (Baltimore, Md.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal approaches (chimeric reporter, Ca2+ imaging, co-expression rescue experiments) in single rigorous study\",\n      \"pmids\": [\"23077345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Biomechanical stress (fluid flow shear stress) increases CaSR expression and causes CaSR localization to the endoplasmic reticulum (ER) in chondrocytes, leading to Ca2+ loading and accelerated chondrocyte terminal differentiation. Chondrocyte-specific Casr knockout prevented UAC-induced acceleration of terminal differentiation and matrix degradation in TMJ cartilage; this was replicated pharmacologically with CaSR antagonist NPS2143.\",\n      \"method\": \"ATDC5 cell shear stress model; chondrocyte-specific Casr conditional KO mice; rat UAC osteoarthritis model; CaSR antagonist injection; CaSR knockdown; ER Ca2+ depletion experiments\",\n      \"journal\": \"Journal of bone and mineral research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO plus pharmacological rescue plus in vitro mechanism, multiple orthogonal approaches across cell and animal models\",\n      \"pmids\": [\"30496623\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Filamin A (FLNA) co-localizes with CaSR in parathyroid adenoma-derived cells and is reduced in parathyroid tumors. FLNA silencing in HEK293 cells reduced CaSR mRNA levels, total and membrane-associated CaSR protein, and CaSR-induced ERK phosphorylation. FLNA expression positively correlates with CaSR expression in parathyroid adenomas.\",\n      \"method\": \"Co-immunoprecipitation/co-localization; FLNA siRNA knockdown in HEK293 cells transfected with CaSR variants; Western blot; correlation analysis in 74 parathyroid adenomas\",\n      \"journal\": \"Journal of molecular endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-localization plus siRNA loss-of-function, single lab with multiple readouts\",\n      \"pmids\": [\"27872158\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"The renal CaSR, Klotho, and ADAM10 co-localize on the basolateral membrane of the distal convoluted tubule (DCT). CaSR activation by calcimimetics or HCO3- increases sKlotho levels in WT but not tubule-specific CaSR-/- mice. CaSR activation stimulates Klotho shedding via ADAM10 protease, as shown by ADAM10 inhibitor (GI254023X) and siRNA.\",\n      \"method\": \"Tubule-specific CaSR KO mice; calcimimetic and alkali treatment; confocal microscopy for CaSR/Klotho/ADAM10 co-localization; ADAM10 inhibitor and siRNA in cultured cells; sKlotho ELISA\",\n      \"journal\": \"Journal of the American Society of Nephrology : JASN\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO mice plus pharmacological/siRNA inhibition plus co-localization, multiple orthogonal approaches in single study\",\n      \"pmids\": [\"34551996\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR mediates magnesium homeostasis: mice lacking both CaSR and PTH showed greater increases in serum Mg and Ca during Mg loading than PTH-null or WT mice, and CaSR loss abrogated calcitonin secretion in response to Mg loading, demonstrating CaSR's direct role in Mg homeostasis independent of PTH.\",\n      \"method\": \"PTH-KO and CaSR/PTH double-KO mouse models; Mg loading experiments; serum measurements of Mg, Ca, PTH, calcitonin, 1,25-dihydroxyvitamin D\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with multiple KO genotypes and multiple mineral challenges clearly separating CaSR and PTH effects\",\n      \"pmids\": [\"23360827\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"CaSR in intestinal epithelial cells mediates anti-inflammatory effects of L-tryptophan: L-Trp reduced TNF-α-induced IL-8 secretion and inhibited JNK and IκBα phosphorylation via CaSR activation. The CaSR antagonist NPS-2143 abrogated these effects. β-arrestin2 was found to block TNF-α-induced signaling pathways after CaSR activation by L-Trp.\",\n      \"method\": \"Caco-2 and HT-29 cell lines; CaSR antagonist (NPS-2143) treatment; Western blot for JNK and IκBα phosphorylation; IL-8 ELISA\",\n      \"journal\": \"Journal of agricultural and food chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological CaSR inhibition with multiple signaling readouts, single lab with two cell lines\",\n      \"pmids\": [\"26551350\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Tryptophan enhances intestinal epithelial barrier integrity and reduces inflammatory responses through the CaSR/Rac1/PLC-γ1 signaling pathway: CaSR activation by tryptophan increases GTP-Rac1 and p-PLC-γ1; Rac1-siRNA, PLC-γ1-siRNA, or CaSR inhibitor blocked tryptophan's protective effects; CaSR overexpression increased cell migration that was reduced by Rac1 or PLC-γ1 silencing.\",\n      \"method\": \"IPEC-J2 cells; CaSR overexpression and CaSR inhibitor (NPS-2143); Rac1-siRNA and PLC-γ1-siRNA; TEER measurement; FITC-dextran permeability; Western blot\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pathway placement by multiple siRNA KDs plus CaSR OE and inhibitor, single lab\",\n      \"pmids\": [\"34745120\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CaSR activates ERK1/2 in pancreatic α cells via Gq (not Gi) signaling to drive hyperaminoacidemia-induced α cell proliferation. CaSR is also required for mTORC1 activation in α cells. Coactivation of Gq and mTORC1 was sufficient to induce α cell proliferation independent of hyperaminoacidemia.\",\n      \"method\": \"Mouse islets and glucagon receptor-deficient zebrafish; CaSR inactivation and rescue experiments; Gq vs. Gi signaling dissection; ERK1/2 activation assays; mTORC1 pathway analysis\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two model organisms, loss-of-function rescue with specific G-protein pathway (Gq vs Gi), mTORC1 mechanistic dissection, multiple orthogonal approaches\",\n      \"pmids\": [\"36646689\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"CaSR activates PKCδ which translocates to the ER to induce ER stress responses and ER stress-associated cardiomyocyte apoptosis during ischemia/reperfusion. CaSR activation with GdCl3 increased CaSR, GRP78, Caspase-12, p-JNK, and Caspase-3 expression and increased apoptotic cell ratios; PKCδ inhibitor (rottlerin) reversed these effects.\",\n      \"method\": \"In vivo rat cardiac I/R model; CaSR activator (GdCl3) and PKCδ inhibitor (rottlerin); Western blot for ER stress markers; apoptosis quantification\",\n      \"journal\": \"International journal of molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological activation/inhibition with mechanistic pathway dissection in vivo, single lab\",\n      \"pmids\": [\"31257458\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"ZnR/GPR39 activity is regulated by the expression and activity of CaSR in prostate and salivary epithelial cells. Co-expression of CaSR and ZnR/GPR39 synergistically enhances Ca2+ responses; CaSR silencing (siRNA or dominant-negative) reduces Zn2+-dependent signaling, while CaSR agonist spermine below threshold enhanced Zn2+-dependent Ca2+ response.\",\n      \"method\": \"CaSR siRNA silencing; dominant-negative CaSR; GPR39 overexpression in HEK293 cells; Ca2+ imaging; pharmacological CaSR activation\",\n      \"journal\": \"Journal of cellular physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA, dominant-negative and reconstitution approaches, single lab\",\n      \"pmids\": [\"24264723\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"CaSR promoter 2 hypermethylation and increased H3K9me3 are epigenetic mechanisms that silence CaSR expression in sporadic parathyroid adenomas. Treatment with 5-aza-2'deoxycytidine (DNA demethylase) restored CaSR expression in a parathyroid cell line. The GCM2 binding site on CaSR promoter 2 showed maximum CpG methylation.\",\n      \"method\": \"Bisulphite sequencing; chromatin immunoprecipitation-qPCR; 5-aza-2'deoxycytidine treatment; qPCR and IHC in 40 adenomas vs. 10 controls\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — bisulphite sequencing plus ChIP-qPCR plus pharmacological demethylation rescue, multiple orthogonal epigenetic methods in primary tumors\",\n      \"pmids\": [\"32609827\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Upper small intestinal CaSR is required for casein infusion to increase glucose tolerance and GLP-1/GIP secretion (in a PepT1-dependent manner). Ileal CaSR (PepT1-independent) is required to lower feeding and increase glucose tolerance with concurrent PYY and GLP-1 release. High-fat diet decreases ileal CaSR expression and disrupts casein sensing on feeding.\",\n      \"method\": \"Upper small intestine and ileum casein infusion in male rats; pharmacological CaSR inhibition; measurement of gut hormones (GLP-1, GIP, PYY); glucose tolerance tests; feeding behavior assays\",\n      \"journal\": \"Nature metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — segment-specific pharmacological inhibition with multiple hormone readouts and behavioral endpoints, mechanistic dissection of CaSR vs. PepT1 pathways\",\n      \"pmids\": [\"38167726\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"CaSR activation promotes M1 macrophage polarization by coupling to TRPV4 channels via PLA2/CYP450 and PLC/PKC pathways, leading to Ca2+ entry and upregulation of M1-associated cytokines IL-1β and TNFα. CaSR-induced Ca2+ signaling was significantly attenuated in TRPV4 knockout macrophages.\",\n      \"method\": \"TRPV4 KO mice peritoneal macrophages; pharmacological CaSR and TRPV4 inhibitors; pathway inhibitors (PLA2/CYP450, PLC/PKC); Ca2+ imaging; cytokine measurement\",\n      \"journal\": \"Acta physiologica (Oxford, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — TRPV4 KO genetic model plus pharmacological pathway dissection, single lab\",\n      \"pmids\": [\"36606511\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"CaSR promotes Rab27B expression and activates this secretory GTPase via PI3K, PKA, mTOR, and MADD (a guanine nucleotide exchange factor) in breast cancer cells, leading to secretion of cytokines and chemokines (IL-6, IL-1β, IL-8, IP-10, RANTES). This regulatory mechanism occurred in MDA-MB-231 and MCF-7 but not non-cancerous MCF-10A cells.\",\n      \"method\": \"CaSR stimulation in breast cancer cell lines; PI3K/PKA/mTOR inhibitors; MADD identification; cytokine secretion assays; Rab27B expression analysis\",\n      \"journal\": \"Biochimica et biophysica acta. Molecular cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple pathway inhibitors plus mechanistic identification of GEF (MADD), single lab\",\n      \"pmids\": [\"33845096\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR expression and function is required for TGFβ receptor expression and cellular responses to TGFβ in human colonic epithelial cells. Knockdown of CaSR abrogated TGFβ-mediated cellular responses and attenuated TGFβ receptor expression; Ca2+ or vitamin D treatment induced CaSR expression with concurrent TGFβ receptor upregulation, but only when CaSR was present.\",\n      \"method\": \"CaSR shRNA knockdown in CBS cells; Ca2+ and vitamin D treatment; TGFβ receptor expression analysis; TGFβ response assays\",\n      \"journal\": \"Cell calcium\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA loss-of-function plus ligand stimulation with mechanistic pathway placement, single lab\",\n      \"pmids\": [\"23639611\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CaSR in esophageal epithelial cells (HET-1A line) mediates Ca2+ stimulation of ERK1/2 activation, intracellular Ca2+ mobilization via PI-PLC (blocked by U73122), and IL-8 secretion. siRNA knockdown of CaSR attenuated these Ca2+-induced responses while responses to acetylcholine remained sustained, confirming CaSR-specific signal transduction.\",\n      \"method\": \"CaSR siRNA transfection in HET-1A cells; PI-PLC inhibitor U73122; ERK Western blot; intracellular Ca2+ microfluorometry (Fluo-4); IL-8 ELISA\",\n      \"journal\": \"American journal of physiology. Gastrointestinal and liver physiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — siRNA-specific knockdown with multiple orthogonal readouts (Ca2+ imaging, kinase activation, cytokine secretion) and pathway inhibitor, single rigorous study\",\n      \"pmids\": [\"17962359\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CaSR signaling in vascular smooth muscle cells (hVSMCs) reduces vascular calcification. Calcimimetics (R-568, AMG 641) promote CaSR protein transport from ER to plasma membrane, increase total and surface CaSR expression, decrease matrix collagen secretion, and reduce mineral deposition by ~90% under pro-mineralizing conditions. These effects required CaSR activation as they were blocked by CaSR siRNA but not scrambled siRNA.\",\n      \"method\": \"hVSMC culture with calcimimetics; CaSR siRNA vs. scrambled siRNA; flow cytometry for surface CaSR; Alizarin red mineralization assay; qRT-PCR for phenotype markers\",\n      \"journal\": \"Cardiovascular research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — siRNA specificity control, multiple orthogonal methods (flow cytometry, mineralization, gene expression), direct rescue with CaSR knockdown demonstrating mechanistic dependence\",\n      \"pmids\": [\"24217682\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CaSR is a family C G protein-coupled receptor that functions as the principal extracellular Ca2+ sensor: it couples to Gq/11, Gi/o, and G12/13 to regulate PTH secretion, renal Ca2+/Mg2+ handling, calcitonin release, and AQP2 trafficking (via p38-MAPK/ubiquitination and miRNA-137); it signals through PLC, PKC, ERK, PI3K/AKT, and mTORC2 via scaffold interactions with Homer1, filamin-A, and caveolin-1; it drives tissue-specific outcomes including skeletal development (chondrocyte/osteoblast differentiation via PLCγ and AKT/β-catenin), intestinal hormone secretion and barrier function (via CaSR/Rac1/PLC-γ1), neuroprotection through antagonistic regulation of GABABR1, and regulation of sKlotho shedding via ADAM10 in renal DCT cells; loss-of-function mutations cause FHH/NSHPT and gain-of-function mutations cause autosomal dominant hypocalcemia.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CASR encodes a family C G protein-coupled receptor that serves as the principal sensor of extracellular calcium, coupling small changes in [Ca2+]o through Gq/11, Gi/o, and G12/13 to PTH secretion, renal cation handling, and calcitonin release [#0, #3]. Its extracellular bi-lobed Venus Flytrap domain binds Ca2+ and transduces activation through a nine-cysteine linker to the seven-transmembrane domain, conferring high cooperativity and ligand-biased responses to agonists such as Sr2+ and modulators including L-amino acids and cinacalcet [#3, #4]. Beyond regulating PTH, CaSR directly defends against hypercalcemia by stimulating calcitonin secretion and renal Ca2+ clearance, and governs Mg2+ homeostasis, independently of PTH [#2, #19]; in the renal tubule it inhibits PTH-driven Ca2+ absorption and regulates NKCC2 in the thick ascending limb, suppresses AQP2 via p38-MAPK/ubiquitination and miR-137, and drives ADAM10-mediated shedding of soluble Klotho in the distal convoluted tubule [#6, #12, #18]. Intracellularly, CaSR organizes compartmentalized signaling through scaffold interactions with filamin-A, caveolin-1, and Homer1, the latter recruiting mTORC2 to phosphorylate AKT-Ser473 and stabilize beta-catenin during osteoblast differentiation [#3, #7, #14]; agonist-driven anterograde trafficking sets steady-state plasma-membrane receptor levels, and filamin-A supports CaSR expression and ERK signaling [#15, #17]. Through these effectors CaSR controls tissue-specific outcomes spanning skeletal and chondrocyte development [#1, #16], intestinal hormone secretion, barrier integrity, and epithelial growth via Wnt5a/Ror2 and Rac1/PLC-gamma1 [#8, #21, #26], pancreatic alpha-cell proliferation via Gq/ERK and mTORC1 [#22], macrophage polarization through TRPV4 [#27], and neuroprotection via functional antagonism of GABABR1 [#10]. Loss-of-function mutations cause familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism, while gain-of-function mutations cause autosomal dominant hypocalcemia [#0]. In sporadic parathyroid adenomas, CaSR is silenced through promoter-2 hypermethylation and H3K9me3 [#25].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Establishing CaSR as a parathyroid/kidney calcium-sensing GPCR whose dose of function maps to distinct mineral disorders defined its core physiological role.\",\n      \"evidence\": \"Mutational analysis with genotype-phenotype correlation and functional variant characterization\",\n      \"pmids\": [\"11013439\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the downstream signaling effectors mediating PTH suppression versus renal handling\", \"Structural basis of activation not defined\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Identifying dual CASR promoters and showing selective silencing of the upstream promoter in parathyroid adenomas connected receptor transcriptional control to tumorigenesis.\",\n      \"evidence\": \"Genomic cloning and Northern blot of adenoma versus normal parathyroid tissue\",\n      \"pmids\": [\"10713061\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of promoter silencing not yet identified\", \"Functional consequence on Ca2+ sensing in tumors not measured\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Tissue-specific knockouts demonstrated nonredundant CaSR roles in early embryogenesis and skeletal development beyond mineral homeostasis.\",\n      \"evidence\": \"Conditional Cre-lox Casr knockouts in parathyroid, bone, and chondrocytes with developmental phenotyping\",\n      \"pmids\": [\"18765830\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Signaling effectors driving chondrocyte/osteoblast phenotypes not defined here\", \"Embryonic lethality mechanism unresolved\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Genetic epistasis with PTH-null mice separated CaSR's PTH-independent defense against hypercalcemia via renal clearance and calcitonin from its PTH-regulating role.\",\n      \"evidence\": \"CaSR/PTH single and double knockout mice with hypercalcemic challenge and serum/urinary measurements\",\n      \"pmids\": [\"19797241\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Renal transport molecules mediating CaSR-dependent Ca2+ clearance not identified\", \"Calcitonin cell signaling pathway not dissected\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Genetic dissection extended CaSR's PTH-independent role to magnesium homeostasis and Mg-stimulated calcitonin secretion.\",\n      \"evidence\": \"PTH-KO and CaSR/PTH double-KO mice with Mg loading and serum measurements\",\n      \"pmids\": [\"23360827\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Renal Mg transporters downstream of CaSR not specified\", \"Tissue site of Mg sensing not localized\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Defining agonist-driven anterograde trafficking and demonstrating that WT receptor rescues mutant trafficking via shared intracellular Ca2+ signaling clarified how membrane receptor levels are set and how dominant mutations behave.\",\n      \"evidence\": \"Chimeric CaSR reporters with simultaneous membrane and Ca2+ imaging and WT/mutant co-expression rescue\",\n      \"pmids\": [\"23077345\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Trafficking machinery and adaptors not identified\", \"Generality across all FHH/NSHPT mutant classes untested\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Cataloguing filamin-A and caveolin-1 as scaffold partners established that CaSR signaling is compartmentally organized.\",\n      \"evidence\": \"Co-immunoprecipitation and signaling analysis synthesized in review\",\n      \"pmids\": [\"22453940\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Review without primary data\", \"Stoichiometry and structural basis of scaffolds not defined\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Synthesis of pharmacology defined CaSR's tripartite G-protein coupling, biased agonism, resistance to desensitization, and VFT/cysteine-rich/7TM domain architecture, framing the receptor as a multi-output signaling hub.\",\n      \"evidence\": \"Review integrating signaling and structural/promoter data\",\n      \"pmids\": [\"23856262\", \"23856260\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Reviews without new primary data\", \"Quantitative bias factors and structural mechanism of biased signaling not resolved\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Multiple tissue studies placed CaSR upstream of distinct effector pathways: TAL Ca2+ transport/NKCC2, intestinal Wnt5a/Ror2 control of epithelial growth, TGFbeta receptor expression, and osteoblast PLC-gamma-driven bone formation.\",\n      \"evidence\": \"Renal tubule disruption, global/colonic CaSR KO mice with cell culture epistasis, shRNA knockdown, and osteoblast/ankylosing spondylitis models\",\n      \"pmids\": [\"18982348\", \"23856267\", \"23639611\", \"33259138\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct physical links between CaSR and these effectors not all established\", \"Mostly single-lab pathway placements\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Pharmacological and reconstitution studies tied extracellular Ca2+/CaSR signaling to mesenchymal/osteoblast differentiation and to cross-regulation of the zinc receptor ZnR/GPR39.\",\n      \"evidence\": \"CaSR blockade in rBMSCs with differentiation assays; CaSR siRNA/dominant-negative and GPR39 co-expression in HEK293 with Ca2+ imaging\",\n      \"pmids\": [\"24525034\", \"24264723\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct receptor cross-talk mechanism with GPR39 not structurally defined\", \"In vivo relevance of GPR39 interplay not tested\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Genetic and pharmacological epistasis revealed a heteromeric CaSR-GABABR1 complex in neurons in which CaSR antagonism is neuroprotective by restoring GABABR1, establishing functional receptor antagonism in ischemia.\",\n      \"evidence\": \"Neuron-specific Casr and Gabbr1 KO mice, forebrain ischemia, calcilytics +/- baclofen, behavioral testing\",\n      \"pmids\": [\"25540800\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular interface of the heteromer not mapped\", \"Signaling consequences of complex formation not fully resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Domain-mapping and ligand studies localized CaSR's ERK1/2-driving region to residues 877-907 (distinct from filamin-A binding) and demonstrated CaSR/ERK-mediated anti-inflammatory effects of L-tryptophan via beta-arrestin2.\",\n      \"evidence\": \"CaSR deletion mutants in sympathetic neurons with ERK inhibition; Caco-2/HT-29 cells with NPS-2143 and signaling readouts\",\n      \"pmids\": [\"26200251\", \"26551350\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct effector binding to the 877-907 region not identified\", \"beta-arrestin2 recruitment mechanism not structurally defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Filamin-A was shown to be required for CaSR expression, membrane localization, and ERK signaling, and CaSR-specific signaling in esophageal epithelium (ERK, PI-PLC Ca2+ mobilization, IL-8) was established by knockdown specificity.\",\n      \"evidence\": \"FLNA siRNA in HEK293 with adenoma correlation; CaSR siRNA in HET-1A cells with U73122 and multiple readouts\",\n      \"pmids\": [\"27872158\", \"17962359\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which FLNA stabilizes CaSR transcript/protein not defined\", \"In vivo relevance of esophageal CaSR signaling untested\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Renal collecting-duct studies identified two parallel CaSR mechanisms suppressing AQP2 (p38-MAPK/Ser261 phosphorylation/ubiquitination and miR-137), linking CaSR to water handling.\",\n      \"evidence\": \"Pendrin/NCC double-KO mice with calcilytic NPS2143, AQP2 Western blot, and miRNA quantification\",\n      \"pmids\": [\"29212817\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Upstream coupling of CaSR to p38 and miR-137 induction not detailed\", \"Relative contribution of the two arms not quantified\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"The Homer1 scaffold was shown to bridge CaSR to mTORC2-dependent AKT-Ser473 phosphorylation, beta-catenin stabilization, and osteoblast differentiation, providing a reconstituted mechanistic chain.\",\n      \"evidence\": \"Reciprocal Co-IP in human osteoblasts, siRNA loss-of-function, and HEK-293 Homer1c/CaSR co-transfection reconstitution\",\n      \"pmids\": [\"31527082\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of the CaSR-Homer1-mTORC2 assembly not solved\", \"In vivo bone phenotype of disrupting this axis not tested\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Additional effector branches were defined: biomechanical-stress-induced ER localization driving chondrocyte terminal differentiation, PKCdelta/ER-stress cardiomyocyte apoptosis, and TRPV4-coupled M1 macrophage polarization.\",\n      \"evidence\": \"Chondrocyte-specific Casr KO with shear-stress and OA models; rat cardiac I/R with rottlerin; TRPV4 KO macrophages with pathway inhibitors\",\n      \"pmids\": [\"30496623\", \"31257458\", \"36606511\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of CaSR relocalization to ER not defined\", \"Direct CaSR-TRPV4 coupling versus indirect lipid signaling not fully separated\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Epigenetic profiling established promoter-2 hypermethylation and H3K9me3 as mechanisms silencing CaSR in sporadic parathyroid adenomas, with demethylase rescue restoring expression.\",\n      \"evidence\": \"Bisulphite sequencing, ChIP-qPCR, and 5-aza-2'deoxycytidine treatment in adenomas and a parathyroid cell line\",\n      \"pmids\": [\"32609827\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Trigger initiating CaSR promoter methylation unknown\", \"Whether silencing is cause or consequence of tumorigenesis not resolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"CaSR was placed in renal sKlotho regulation and in cancer secretory signaling: it drives ADAM10-mediated Klotho shedding in the DCT and Rab27B-dependent cytokine secretion in breast cancer cells.\",\n      \"evidence\": \"Tubule-specific CaSR KO mice with ADAM10 inhibitor/siRNA and co-localization; breast cancer lines with PI3K/PKA/mTOR inhibitors and MADD identification\",\n      \"pmids\": [\"34551996\", \"33845096\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How CaSR activates ADAM10 mechanistically not defined\", \"Cancer-cell-selectivity of the Rab27B pathway not mechanistically explained\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"CaSR/Rac1/PLC-gamma1 signaling was defined as the pathway by which tryptophan enhances intestinal epithelial barrier integrity and migration.\",\n      \"evidence\": \"IPEC-J2 cells with CaSR overexpression/inhibitor and Rac1/PLC-gamma1 siRNA, TEER and permeability assays\",\n      \"pmids\": [\"34745120\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct CaSR-Rac1 coupling intermediary (GEF) not identified\", \"Single cell-line, in vivo validation lacking\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"G-protein-selective dissection showed CaSR drives pancreatic alpha-cell proliferation via Gq/ERK and mTORC1 during hyperaminoacidemia, with Gq+mTORC1 coactivation sufficient.\",\n      \"evidence\": \"Mouse islets and glucagon-receptor-deficient zebrafish with CaSR loss/rescue and Gq-versus-Gi dissection\",\n      \"pmids\": [\"36646689\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How CaSR selectively engages Gq over Gi in alpha cells not explained\", \"Link between Gq/ERK and mTORC1 activation not fully mapped\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Segment-specific intestinal studies defined CaSR as a casein/amino-acid sensor controlling incretin and satiety hormone release and glucose tolerance, with high-fat diet impairing ileal CaSR sensing.\",\n      \"evidence\": \"Upper-intestine and ileum casein infusion in rats with CaSR inhibition, gut hormone measurements, and feeding/glucose-tolerance assays\",\n      \"pmids\": [\"38167726\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Enteroendocrine cell-intrinsic signaling downstream of CaSR not dissected\", \"Mechanism of HFD-induced CaSR downregulation unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A unified structural and quantitative model of how a single calcium-sensing receptor selects among Gq/11, Gi/o, G12/13, and arrestin outputs and among distinct scaffolds to produce tissue-specific outcomes remains unresolved.\",\n      \"evidence\": \"No single discovery in the corpus integrates biased coupling, scaffold selection, and tissue context mechanistically\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model linking ligand bias to G-protein/scaffold selection\", \"Tissue-specific determinants of effector choice not defined\", \"In vivo relevance of many single-lab effector pathways untested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [0, 3, 4]},\n      {\"term_id\": \"GO:0140299\", \"supporting_discovery_ids\": [0, 3, 4, 26]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [7, 14, 17]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 15, 31]},\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [16, 23, 31]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [3, 14, 22]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [2, 6, 19]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [1, 8, 16]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [0, 6, 25]}\n    ],\n    \"complexes\": [\n      \"CaSR-GABABR1 heteromer\",\n      \"CaSR-Homer1-mTORC2 complex\"\n    ],\n    \"partners\": [\n      \"FLNA\",\n      \"CAV1\",\n      \"HOMER1\",\n      \"GABBR1\",\n      \"GPR39\",\n      \"TRPV4\",\n      \"ADAM10\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}