| 2007 |
Targeted disruption of AdipoR2 in mice resulted in decreased PPAR-alpha signaling pathway activity. Simultaneous disruption of AdipoR1 and AdipoR2 abolished adiponectin binding entirely. Adenovirus-mediated hepatic overexpression of AdipoR2 increased PPAR-alpha signaling and fatty acid oxidation, ameliorating diabetes in Lepr(-/-) mice. |
Targeted gene knockout mice, adenovirus-mediated overexpression in vivo, adiponectin binding assays, metabolic phenotyping |
Nature medicine |
High |
17268472
|
| 2008 |
Hepatic AdipoR2 signaling regulates PPAR-alpha activity and catalase expression, thereby controlling lipid peroxidation (ROS accumulation). Adenoviral knockdown of AdipoR2 aggravated NASH by diminishing PPAR-alpha/ACO/catalase expression, while overexpression improved steatohepatitis by enhancing PPAR-alpha activity and reducing TGF-beta1-induced ROS in primary hepatocytes. |
Adenoviral shRNA knockdown and overexpression in vivo (MCD diet mouse model), primary hepatocyte cultures, PPAR-alpha signaling assays, ROS measurement |
Hepatology (Baltimore, Md.) |
High |
18666257
|
| 2008 |
AdipoR1 and AdipoR2 activate ERK1/2 through a Src/Ras-dependent pathway. Adiponectin-induced ERK1/2 activation required APPL1 (adaptor protein), was abolished by Src family kinase inhibitor PP2 and Clostridium difficile toxin B (small GTPase inhibitor), and was associated with Src-dependent Ras (but not Rap1) activation. Either receptor alone was sufficient to mediate ERK1/2 activation. |
RNAi knockdown in HEK293 cells, pharmacological inhibitors (PP2, PKA inhibitor, toxin B), Ras activation assays, cell growth assays with overexpression |
Biochemistry |
Medium |
18842004
|
| 2010 |
ERp46 interacts specifically with AdipoR1 but NOT AdipoR2. The interaction is mediated by the cytoplasmic N-terminal residues (1-70) of AdipoR1. ERp46 is present at both ER and plasma membrane. Knockdown of ERp46 increased surface levels of both AdipoR1 and AdipoR2 and enhanced adiponectin-stimulated AMPK phosphorylation, but reduced p38MAPK phosphorylation. |
Co-immunoprecipitation followed by mass spectrometry, GST-fusion protein pulldown with truncated constructs, indirect immunofluorescence, subcellular fractionation, transient siRNA knockdown, AMPK and p38MAPK phosphorylation assays |
Biochemical and biophysical research communications |
Medium |
20074551
|
| 2010 |
ATF3, induced by ER stress, transcriptionally represses AdipoR2 expression. ER stress inducer thapsigargin decreased AdipoR2 protein and RNA levels concomitant with ATF3 induction. Chromatin immunoprecipitation and EMSA identified a specific ATF3-binding site at nucleotides -94 to -86 of the AdipoR2 promoter. Chemical chaperone PBA reversed these effects. |
Reporter gene assays with 5'-deleted AdipoR2 promoter constructs, ATF3 overexpression/knockdown, EMSA, chromatin immunoprecipitation, ob/ob mouse liver analysis |
The FEBS journal |
High |
20423458
|
| 2011 |
In human macrophage foam cell formation, AdipoR2 (but not AdipoR1) is the dominant receptor for adiponectin suppression of scavenger receptor A type 1 (SR-AI) and upregulation of IL-1Ra. Both AdipoR1 and AdipoR2 are required for adiponectin-mediated suppression of lipid accumulation. APPL1 knockdown abrogated adiponectin inhibition of lipid accumulation, SR-AI, NF-κB, and Akt phosphorylation. |
Overexpression and lentiviral-shRNA knockdown of AdipoR1, AdipoR2, and APPL1 in THP-1 monocytes, oxLDL-induced foam cell transformation, gene expression assays |
Atherosclerosis |
Medium |
22227293
|
| 2013 |
In C. elegans, PAQR-2 (AdipoR2 homolog) regulates fatty acid desaturation required for membrane fluidity during cold adaptation. Genetic suppressors of paqr-2 include genes in phosphatidylcholine synthesis and fatty acid metabolism pathways (sbp-1, Δ9-desaturases), establishing a cold adaptation pathway: paqr-2 → phosphatidylcholines/sbp-1 → Δ9-desaturases → unsaturated fatty acids → membrane fluidity. |
C. elegans suppressor screen, genetic epistasis analysis, fatty acid composition measurements, lipid analysis |
PLoS genetics |
High |
24068966
|
| 2013 |
The non-conserved N-terminal region of AdipoR2 (residues 1-81) restricts its cell-surface expression. AdipoR1 is constitutively expressed at the cell surface, but AdipoR2 is not. Introduction of the AdipoR2 N-terminal region into AdipoR1 inhibited its surface expression; deletion from AdipoR2 promoted surface expression. AdipoR1 and AdipoR2 can form heterodimers, and co-expression enables AdipoR2 cell-surface localization. |
C-terminal epitope-tagged chimeric and truncated constructs, indirect immunofluorescence microscopy, quantitative plate-based surface expression analysis in HEK293 cells |
Biochemical and biophysical research communications |
Medium |
23376713
|
| 2014 |
AdipoR2 deficiency in mice severely attenuated revascularization after hind limb ischemic surgery, and adiponectin treatment failed to rescue AdipoR2-deficient mice. In contrast, AdipoR2-deficient mice were protected from diet-induced obesity and metabolic dysfunction. AdipoR1 deficiency led to metabolic dysfunction but not vascular defects, revealing divergent receptor functions in vascular vs. metabolic homeostasis. |
AdipoR1- and AdipoR2-knockout mice, hind limb ischemia surgery model, diet-induced obesity model, blood flow recovery measurements, metabolic phenotyping |
The Journal of biological chemistry |
High |
24742672
|
| 2015 |
AdipoR2 N-terminal truncation mutant (AdipoR2Δ99, residues 100-386) expressed as monodisperse protein in insect cells and was crystallized with anti-AdipoR1 Fv fragment by the lipidic mesophase method, yielding X-ray diffraction data to 2.4 Å resolution. Thermostability, thin-layer chromatography of bound lipids, and SPR ligand binding analyses confirmed structural integrity. |
Recombinant protein expression in insect cells, affinity and gel-filtration chromatography, thermostability assay, TLC, SPR, lipidic mesophase crystallization, X-ray diffraction |
Journal of structural and functional genomics |
Medium |
25462574
|
| 2015 |
Cell-surface expression of AdipoR1 and AdipoR2 is required for effective downstream signaling. Adiponectin induces internalization of both receptors. The non-conserved N-terminal trunks (AdipoR1 residues 1-70; AdipoR2 residues 1-81) define divergent temporal signaling profiles: AdipoR1 signals peak at 15 min; AdipoR2 signals peak at 24 h. |
Transient expression of AdipoR1/R2 and chimeric constructs in HEK293 cells, serum-starvation, cell-surface expression quantification, phosphorylation time-course analysis of downstream effectors |
Molecular and cellular endocrinology |
Medium |
25892445
|
| 2016 |
AdipoR2 (but not AdipoR1) in the dentate gyrus is necessary and sufficient for adiponectin-mediated facilitation of contextual fear extinction and suppression of intrinsic excitability of dentate gyrus granule neurons. Deletion of AdipoR2 in the DG caused augmented fear expression, reduced extinction, and intrinsic hyperexcitability. AdipoRon failed to suppress excitability in AdipoR2 knockout mice. |
Conditional AdipoR1/R2 knockout in dentate gyrus, contextual fear conditioning and extinction behavioral tests, whole-cell patch-clamp recordings in brain slices, AdipoRon pharmacology |
Molecular psychiatry |
High |
27137743
|
| 2016 |
C. elegans paqr-2 (AdipoR2 homolog) mutants lacking paqr-2 or its partner iglr-2 are glucose intolerant and die in the presence of low glucose concentrations. PAQR-2 and IGLR-2 interact on plasma membranes (shown by bimolecular fluorescence complementation) and act as a fluidity sensor controlling membrane lipid composition via FRAP-measured membrane fluidity. This pathway is independent of the insulin receptor/FoxO (daf-2/daf-16) pathway. |
C. elegans genetics, FRAP (Fluorescence Recovery After Photobleaching) on living worms, bimolecular fluorescence complementation, genetic epistasis with daf-2/daf-16 |
PLoS genetics |
High |
27082444
|
| 2017 |
AdipoR2 and its C. elegans homolog PAQR-2 are essential to counter membrane rigidification by exogenous saturated fatty acids. siRNA knockdown of AdipoR2 in mammalian cells prevented cells from counteracting the membrane-rigidifying effects of palmitic acid. Dietary SFA-rich diets cause membrane rigidity and lethality in paqr-2 mutants, rescued by dietary unsaturated FA supplements or genetic suppressors. |
C. elegans dietary supplementation with saturated/monounsaturated FAs, direct membrane fluidity measurements, AdipoR2 siRNA knockdown in mammalian cells, lipidomics |
PLoS genetics |
High |
28886012
|
| 2017 |
AdipoR2 modulates collagen 1-alpha1 (Col1-α1) and alpha-SMA gene expression, hepatic stellate cell (HSC) migration, and AMPK activity in primary HSCs. AdipoR2 KO mice showed enhanced fibrotic gene expression (Col1-α1, TGF-β1, TIMP-1, IL-10, MMP-2, MMP-9) after CCl4-induced fibrosis, identifying AdipoR2 as the major adiponectin receptor on HSCs mediating anti-fibrotic effects. |
AdipoR1 and AdipoR2 KO mice with CCl4 fibrosis model, siRNA knockdown in primary HSCs, HSC migration assays, AMPK activity, gene expression analysis |
Biochimica et biophysica acta. Molecular basis of disease |
Medium |
29237572
|
| 2017 |
Muscle-specific overexpression of AdipoR2 (but not AdipoR1) in tibialis anterior muscle increased PPARα and ACOX1 (acox1) expression, and uniquely promoted systemic effects in obese mice including decreased weight gain, reduced epididymal fat mass, reduced epididymal inflammation, and increased circulating adiponectin. |
In vivo electrotransfer-mediated overexpression of AdipoR1 or AdipoR2 in tibialis anterior muscle of lean and obese mice, tissue gene expression, metabolic phenotyping |
Scientific reports |
Medium |
28145500
|
| 2018 |
PAQR-2 (AdipoR2 homolog) regulates membrane homeostasis cell nonautonomously in C. elegans: expression of paqr-2 in the hypodermis, gonad sheath cells, or intestine is sufficient to suppress systemic paqr-2 mutant membrane phenotypes in other tissues. In human HEK293 cells, AdipoR2-expressing cells normalize membrane fluidity in distant AdipoR2-silenced cells. Δ9 desaturases (SCD) are essential for this cell-nonautonomous membrane homeostasis. |
C. elegans mosaic analysis, tissue-specific rescue constructs, FRAP in C. elegans intestinal cells, siRNA against SCD in HEK293 cells, co-culture experiments |
Genetics |
High |
29997234
|
| 2019 |
AdipoR1 and AdipoR2 are essential for sustaining desaturase expression and high levels of unsaturated fatty acids in membrane phospholipids in many human cell types including primary HUVECs. Three independent methods (FRAP, Laurdan dye GP, mass spectrometry of phospholipid FA composition) confirm their role as membrane fluidity regulators. Critically, AdipoRs can prevent lipotoxicity in the complete absence of adiponectin, indicating their primary cellular function is membrane homeostasis independent of adiponectin ligand. |
AdipoR1/R2 siRNA knockdown in multiple human cell types, FRAP, Laurdan generalized polarization, phospholipid FA composition by mass spectrometry, palmitate challenge |
Journal of lipid research |
High |
30890562
|
| 2019 |
C. elegans PAQR-2 (AdipoR2 homolog) senses temperature drop and promotes biosynthesis of γ-linolenic acid and arachidonic acid (ω-6 PUFAs), which initiate autophagy in the epidermis, delaying age-dependent collagen decline and extending lifespan at low temperature. |
C. elegans genetics, lipidomics, autophagy assays, lifespan analysis, epistasis with fatty acid biosynthesis genes |
Nature communications |
Medium |
31197136
|
| 2021 |
AdipoR2 deficiency causes extensive transcriptome misregulation and membrane defects in cells challenged with saturated fatty acids (SFAs). Transcriptomics and lipidomics showed AdipoR2 responds to membrane rigidification by regulating lipid metabolism genes. AdipoR2 deficiency phenocopies SREBP deficiency upon SFA challenge. Among AdipoR2, SCD, FADS2, PEMT and ACSL4, AdipoR2 and SCD are the most important for preventing membrane rigidification by exogenous SFAs. |
Transcriptomics, lipidomics, growth and respiration assays, membrane property analyses in HEK293 and HUVEC cells with AdipoR2 KO or knockdown, comparative gene silencing of multiple lipid metabolism genes |
Biochimica et biophysica acta. Molecular and cell biology of lipids |
High |
33444759
|
| 2021 |
C. elegans forward genetic screen identified that only the PAQR-2/IGLR-2 pathway (homologous to human AdipoR2) is uniquely essential for tolerance to dietary saturated fatty acids. FRET analysis showed that the PAQR-2/IGLR-2 interaction is regulated by membrane fluidity, indicating a membrane fluidity-sensing mechanism. N-terminal truncation of PAQR-2 showed the cytoplasmic domain is dispensable but IGLR-2 interaction remains required. |
C. elegans whole-organism forward genetic screen, lipidomics, membrane fluidity measurements, FRET-based protein interaction assay, PAQR-2 domain deletion analysis |
Biochimica et biophysica acta. Molecular and cell biology of lipids |
High |
33444761
|
| 2021 |
AdipoR2 silencing in the presence of exogenous palmitic acid potently increases dihydroceramide levels (ceramide precursor in de novo synthesis), consistent with AdipoR2 silencing increasing intracellular palmitic acid supply driving serine palmitoyl transferase activity. AdipoR2 overexpression caused depletion of dihydroceramides. |
AdipoR2 siRNA knockdown and overexpression in cultured cells, sphingolipid lipidomics, comparison with SCD and SREBF1/2 silencing |
Lipids in health and disease |
Medium |
34839823
|
| 2022 |
RNF145 is an E3 ubiquitin ligase that ubiquitinates and promotes degradation of ADIPOR2 in unsaturated lipid membranes. When membranes become enriched in saturated FAs, RNF145 auto-ubiquitinates and is itself degraded, stabilizing ADIPOR2. ADIPOR2 hydrolase activity then restores lipid homeostasis and prevents lipotoxicity. RNF145 and ADIPOR2 form an autoregulatory loop controlling membrane lipid composition. |
Systematic proteomics identifying differentially expressed proteins with saturated vs. unsaturated FA feeding, ubiquitination assays, RNF145 and ADIPOR2 degradation assays, lipid homeostasis and lipotoxicity assays in mammalian cells |
The EMBO journal |
High |
35993436
|
| 2023 |
AdipoR2 promotes elongation and incorporation of polyunsaturated fatty acids into phospholipids. Immunoprecipitation of tagged AdipoR2 followed by mass spectrometry identified evolutionarily conserved interactors including the dehydratase HACD3 (essential for fatty acid elongation step 3) and ACSL4 (activates unsaturated FAs for phospholipid incorporation). 13C-labeled FA tracing confirmed AdipoR2 promotes FA elongation. These interactions are functionally verified. |
Immunoprecipitation of tagged AdipoR2 and PAQR-2 from HEK293 cells and C. elegans followed by mass spectrometry, 13C-labeled fatty acid tracing, functional interaction validation experiments |
The Journal of biological chemistry |
High |
37164154
|
| 2024 |
AdipoR2 regulates the meiosis-specific lipidome in mouse testes by promoting synthesis of very-long-chain polyunsaturated fatty acids (VLC-PUFAs) in sphingolipids and phospholipids. AdipoR2 upregulates fatty acid elongase ELOVL2 both transcriptionally and post-transcriptionally. AdipoR2 KO testes accumulate palmitic acid and show membrane stiffening, causing nuclear envelope invagination, impaired meiotic telomere peripheral distribution, errors in homologous synapsis and recombination, and defective intercellular bridge formation. |
AdipoR2 knockout mice, testis lipidomics, ELOVL2 expression analysis (transcriptional and post-transcriptional), nuclear envelope ultrastructure analysis, meiotic telomere distribution assays, synapsis/recombination analysis, germ cell syncytium analysis |
Nature communications |
High |
38485951
|
| 2024 |
AdipoR2 KO mice have brains with excessive phospholipid saturation (excess palmitic acid at expense of oleic acid in phosphatidylcholines, ~12% increase in saturated FA in PC), consistent with a defect in fatty acid desaturation and elongation. Older AdipoR2 KO mice are hyperactive and anxious, do not gain weight in old age, and have lower cell density in the cerebrum, but have normal lifespans. |
AdipoR2 KO mice, lipidomics of brain phospholipids at 2/7/18 months, histology, electron microscopy, proteomics, behavioral tests (hyperactivity, anxiety) |
FASEB journal |
Medium |
38989587
|
| 2024 |
SCM-198 selectively binds AdipoR2 with the R335 residue critical for SCM-198-AdipoR2 binding and Y274 serving as a molecular switch for Ca2+ influx. SCM-198-AdipoR2 binding causes Ca2+ influx and elevates phosphorylation of CaMKII and NOS3 within an identified AdipoR2-CaM-CaMKII-NOS3 complex, rapidly inducing nitric oxide production that protects against acute liver failure. |
Molecular docking, site-directed mutagenesis of AdipoR2 (R335, Y274 residues), Ca2+ influx measurements, co-immunoprecipitation of AdipoR2-CaM-CaMKII-NOS3 complex, phosphorylation assays, NO production measurement, mouse ALF model, human ESC-derived liver organoids |
Nature communications |
High |
39681560
|
| 2006 |
Adiponectin downregulates the expression of its own receptor AdipoR2 (but not AdipoR1) both in vivo (transgenic mice overexpressing adiponectin in adipose tissue showed decreased AdipoR2 mRNA) and in vitro (recombinant adiponectin added to 3T3-F442A adipocytes decreased AdipoR2 mRNA). Conversely, AdipoR2 (but not AdipoR1) was specifically upregulated in fat of adiponectin-null mice, establishing a specific negative feedback loop. |
Transgenic mice with adipose-targeted adiponectin expression, adiponectin-KO mice, 3T3-F442A adipocyte cell culture with recombinant adiponectin, RT-PCR and protein quantification |
Biochemical and biophysical research communications |
Medium |
16729974
|
| 2009 |
In human granulosa KGN cells, AdipoR2 knockdown reduced progesterone and estradiol production and lower StAR protein levels in response to FSH or IGF-1 stimulation. AdipoR2 knockdown also reduced adiponectin/FSH-induced MAPK ERK1/2 phosphorylation. In contrast, AdipoR1 knockdown caused apoptosis (increased cleaved caspase-3, decreased BAD phosphorylation and PCNA), indicating differential roles: AdipoR1 in cell survival, AdipoR2 in steroid production via ERK1/2. |
RNAi knockdown of AdipoR1 and AdipoR2 in KGN cells, steroid hormone RIA, western blot for signaling proteins, tritiated thymidine proliferation assay |
Human reproduction (Oxford, England) |
Medium |
19671624
|
| 2010 |
AdipoR2 signaling in the anterior cingulate cortex (ACC) contributes to alcohol-related behaviors. AdipoR2 expression in the ACC was differentially regulated by alcohol in a K-ras-dependent manner. AdipoR2 null mice showed attenuated withdrawal-associated increased drinking. Adiponectin increased the excitability of ACC neurons, more pronounced during alcohol withdrawal. |
Gene expression analysis in ACC, AdipoR2 null mice behavioral testing (alcohol drinking), intracellular electrophysiological recordings of ACC neurons during alcohol withdrawal |
Brain research |
Medium |
20380822
|
| 2021 |
CTRP3 suppresses Th17 cell differentiation via AdipoR2 (but not AdipoR1). Suppression of Th17 differentiation by CTRP3 was abolished by an AdipoR2 receptor antagonist but not an AdipoR1 antagonist, and was associated with suppression of Rorc and Stat3 expression. AdipoRon also suppressed Th17 differentiation via AdipoR2. |
T cell differentiation assays, AdipoR1/R2 receptor antagonists, C1qtnf3 knockout mice, EAE (experimental autoimmune encephalomyelitis) model, AdipoRon treatment |
Frontiers in immunology |
Medium |
34925309
|
| 2023 |
Emodin succinate monoethyl ester (ESME) activates AdipoR2 by forming an arene-arene interaction (molecular docking). Fluorescent ESME labels AdipoR2 on the cytomembrane of HepG2 cells. ESME activates AdipoR2, AMPK (via CaMKK2 and LKB1), and PPARα to reduce hepatic lipogenesis. AdipoR2 suppression completely eliminates ESME's lipid-lowering effect. |
Molecular docking, fluorescent ligand labeling on cell membranes, AdipoR2 siRNA knockdown, AMPK/PPARα signaling assays, lipid accumulation assays, in vivo hamster and mouse models |
Free radical biology & medicine |
Medium |
37044149
|
| 2024 |
AdipoR2 regulates luteal steroidogenesis specifically through AMPK. APN (1 μg/mL) or AdipoRon (25 μM) increased P-AMPK in goat luteal cells and decreased progesterone (P4) and steroidogenic protein levels (STAR/CYP11A1/HSD3B) after 24h. APN failed to affect P-AMPK, CYP11A1 expression, or P4 levels when AdipoR2 was silenced (SiAdipoR2), while silencing AdipoR1 or T-cadherin did not block this pathway. |
Primary goat luteal steroidogenic cell culture, AdipoRon and APN treatment, siRNA knockdown of AdipoR1, AdipoR2, and T-cadherin, AMPK phosphorylation and steroidogenic protein western blots, progesterone RIA |
Cells |
Medium |
37408227
|