{"gene":"RDH10","run_date":"2026-06-10T06:43:36","timeline":{"discoveries":[{"year":2007,"finding":"RDH10 catalyzes the first oxidative step of vitamin A metabolism — the oxidation of retinol to retinal — and is required for embryonic retinoic acid synthesis. A missense mutation in RDH10 (trex allele) abolishes this retinol dehydrogenase activity, resulting in insufficient RA signaling and craniofacial, limb, and organ defects.","method":"ENU forward genetic screen, protein modeling, enzymatic activity assays, and analysis of mutant embryos","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1 / Strong — enzymatic assays combined with mutagenesis and in vivo genetic model, replicated across multiple subsequent studies","pmids":["17473173"],"is_preprint":false},{"year":2004,"finding":"RDH10 is expressed in retinal Müller cells (in addition to RPE) and its all-trans retinol dehydrogenase activity localizes to the microsomal fraction, using NADP as a preferred cofactor in those cells. It generates all-trans retinal, which serves as substrate for the photoisomerase RGR in Müller cells.","method":"Western blot, immunohistochemistry, RT-PCR, HPLC-based retinol dehydrogenase activity assay on microsomal fractions of rMC-1 cells","journal":"Investigative ophthalmology & visual science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (IHC, enzymatic assay, HPLC) in a single lab study","pmids":["15505029"],"is_preprint":false},{"year":2008,"finding":"Human RDH10 is a strictly NAD+-dependent enzyme (not NADP+-dependent as initially reported) with multisubstrate specificity, recognizing both all-trans-retinol and cis-retinols as substrates. It has an exceptionally low apparent Km for all-trans-retinol (~0.035 µM) but a relatively high Km for NAD+ (~100 µM). RDH10 functions exclusively in the oxidative direction in cells, increasing retinaldehyde and retinoic acid levels. siRNA-mediated knockdown of endogenous RDH10 in human cells significantly decreases retinoic acid production from retinol.","method":"Kinetic enzymatic assays with purified recombinant enzyme, cofactor specificity assays, siRNA knockdown with retinoid quantification","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — rigorous in vitro kinetic analysis with mutagenesis-level specificity assays plus siRNA functional validation, single lab with multiple orthogonal methods","pmids":["18502750"],"is_preprint":false},{"year":2009,"finding":"RDH10 oxidizes 11-cis-retinol to 11-cis-retinaldehyde in vitro (11-cis-RDH activity), stimulated by CRALBP. In a reconstituted visual cycle cell culture model (RDH10 + RPE65 + LRAT + CRALBP co-expression), 11-cis-retinaldehyde is generated from all-trans-retinol. RDH10 physically interacts with CRALBP and RPE65 by co-immunoprecipitation and co-localizes with them in bovine RPE cells.","method":"In vitro 11-cis-RDH activity assay in COS1 cells, reconstituted visual cycle in HEK-293A cells, co-immunoprecipitation, immunohistochemistry, HPLC retinoid profiling","journal":"Investigative ophthalmology & visual science","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — reconstitution of visual cycle pathway, co-IP for physical interaction, and in vitro enzymatic assay, multiple orthogonal methods in single study","pmids":["19458327"],"is_preprint":false},{"year":2011,"finding":"RDH10 is the primary retinol dehydrogenase responsible for the first oxidative step of embryonic vitamin A metabolism. The initial retinol-to-retinal conversion occurs predominantly in a membrane-bound cellular compartment, which prevents inhibition by cytosolic CRBP1 (RBP1). Cytosolic enzymes with RDH activity play a very limited role under normal dietary conditions.","method":"Rdh10trex mutant embryos, dietary retinaldehyde supplementation, RDH activity assays on membrane vs. cytosolic fractions","journal":"Developmental biology","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — genetic loss-of-function model combined with biochemical fractionation and dietary rescue, replicated across labs","pmids":["21782811"],"is_preprint":false},{"year":2011,"finding":"RDH10 (via RA synthesis) is required for interdigital tissue loss but not for limb patterning per se. In Rdh10trex/trex mutants, RA activity is absent from limb mesoderm but present in neuroectoderm; restoration with 25 nM RA rescues RARE-lacZ activity in limb mesoderm. Meis2 and Shh expression and skeletal patterning are normal in Rdh10 mutant hindlimbs despite absent limb RA.","method":"RARE-lacZ RA-reporter transgene, exogenous RA rescue, skeletal staining, in situ hybridization in Rdh10trex/trex mutant embryos","journal":"Developmental dynamics","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with reporter rescue and skeletal phenotyping, multiple orthogonal readouts","pmids":["21360789"],"is_preprint":false},{"year":2012,"finding":"Rdh10 associates predominantly with mitochondria/mitochondrial-associated membrane (MAM) in the absence of lipid droplet biosynthesis, but relocates to lipid droplets during acyl ester biosynthesis. The 32 N-terminal residues (including a hydrophobic region followed by net positive charge) are required for lipid droplet targeting; both N-terminal and 48 C-terminal hydrophobic residues are required for mitochondria/MAM targeting and/or protein stability. Co-localization of Rdh10, CRBP1, and LRAT on lipid droplets suggests a metabolon for retinol homeostasis.","method":"Subcellular fractionation, domain deletion mutants, fluorescence colocalization, cell biology assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — domain mutagenesis combined with fractionation and colocalization in a single lab study","pmids":["23155051"],"is_preprint":false},{"year":2013,"finding":"In human monocyte-derived dendritic cells, RDH10, RALDH2, and CRABP2 form a linear PPARγ-regulated pathway required for ATRA production. All three proteins are co-regulated by PPARγ activation and all three are required for ATRA synthesis induced by PPARγ-activating fatty acids.","method":"siRNA knockdown of RDH10, RALDH2, and CRABP2 in human mo-DCs with ATRA measurement; PPARγ activation assays; colocalization in gut-associated lymphoid tissue DCs","journal":"Journal of lipid research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional knockdown with pathway placement, single lab, multiple components tested","pmids":["23833249"],"is_preprint":false},{"year":2017,"finding":"Rdh10 is specifically required in non-neural crest cells prior to E10.5 for proper choanae formation. Loss of Rdh10 leads to ectopic Fgf8 expression in the nasal fin, decreased cell proliferation, and increased cell death in the nasal cavity epithelium, retarding invagination and causing fully penetrant choanal atresia.","method":"Conditional/temporal Rdh10 mutant mouse analysis, cell lineage tracing, in situ hybridization for Fgf8, cell proliferation and apoptosis assays","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-type-specific and stage-specific genetic requirement established with molecular readouts, single lab","pmids":["28169399"],"is_preprint":false},{"year":2018,"finding":"Rdh10 heterozygous hypomorphs produce ~25% less atRA in liver and adipose tissue, leading to escalated adipogenesis, increased adiposity under high-fat diet, liver steatosis, glucose intolerance, and insulin resistance. Embryonic fibroblasts with Rdh10 knockout show decreased atRA biosynthesis and escalated adipogenesis reversible by atRA or RAR pan-agonist treatment.","method":"Rdh10 heterozygote and knockout mouse models, atRA quantification by LC-MS, adipogenesis assays, metabolic phenotyping, pharmacological rescue with atRA","journal":"Diabetes","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic loss-of-function with biochemical atRA quantification and pharmacological rescue, multiple orthogonal metabolic readouts","pmids":["29321172"],"is_preprint":false},{"year":2018,"finding":"RDH10-mediated retinol metabolism and RARα-mediated RA signaling are required for submandibular salivary gland initiation. RDH10 and RALDH2 are expressed in the SMG mesenchyme at the initiation site, and ex vivo assays demonstrate that RDH10 and RA are both required for SOX9 expression and epithelial invagination. The RA requirement acts specifically through RARα with no contribution from other RAR isoforms.","method":"Ex vivo salivary gland initiation assay, stage-specific Rdh10 inactivation, RAR isoform-specific inhibitors/agonists, in situ hybridization","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ex vivo functional assay combined with genetic loss-of-function and pharmacological RAR isoform dissection, single lab","pmids":["29986869"],"is_preprint":false},{"year":2019,"finding":"RDH10 function (via RA synthesis) is required for spontaneous fetal mouth movement that facilitates palate shelf elevation. Rdh10-deficient embryos display mispatterned pharyngeal nerves and skeletal elements that physically block fetal mouth movement in utero, causing cleft palate through a mechanical (movement-dependent) mechanism rather than a direct tissue defect in the palate shelf.","method":"Stage-specific Rdh10 inactivation, X-ray microtomography, in utero ultrasound video, ex vivo culture, tissue staining of pharyngeal nerves and skeletal elements","journal":"Disease models & mechanisms","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct imaging of fetal mouth movement combined with genetic loss-of-function, novel mechanistic pathway placement, single lab","pmids":["31300413"],"is_preprint":false},{"year":2007,"finding":"Forced over-expression of RDH10 in HepG2 hepatocellular carcinoma cells increases endogenous RA concentration (measured by RARE-CAT reporter), causes antiproliferative effects without apoptosis, and is associated with upregulation of RARβ and p21Cip1 and downregulation of CyclinE/CDK2 mRNAs.","method":"Stable RDH10 over-expression in HepG2 cells, RARE-CAT reporter assay, RT-PCR for cell cycle gene expression, proliferation assays","journal":"Cancer biology & therapy","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single over-expression experiment with indirect RA measurement and mRNA readouts, single lab, single method per endpoint","pmids":["17218779"],"is_preprint":false},{"year":2025,"finding":"Rdh10 knockout embryos fail to form a proper optic cup. Combined ChIP-seq (H3K27ac) and RNA-seq on eye tissue identified Alx1 as a direct RA target gene with an RA response element (RARE) near an RA-regulated H3K27ac mark. CRISPR/Cas9 knockout of Alx1 phenocopies Rdh10 KO in optic cup formation, placing Alx1 downstream of RDH10-mediated RA synthesis in eye development.","method":"Rdh10 knockout mouse, ChIP-seq for H3K27ac, RNA-seq on eye tissue, CRISPR/Cas9 Alx1 knockout, in situ hybridization","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis combined with epigenomic (ChIP-seq) and transcriptomic evidence plus CRISPR functional validation, preprint not yet peer-reviewed","pmids":["bio_10.1101_2025.06.24.661406"],"is_preprint":true},{"year":2025,"finding":"Rdh10 is highly expressed in the mesenchyme surrounding the entrance to the foregut and is essential between E7.5–E9.5 for vagal neural crest cell invasion into the gut. Rdh10 loss-of-function embryos exhibit intestinal aganglionosis; NCC form and migrate normally but fail to invade the foregut. RNA-seq revealed downregulation of the Ret-Gdnf-Gfrα1 signaling network and altered extracellular matrix (increased collagen deposition) in the NCC microenvironment.","method":"Rdh10 loss-of-function mouse, stage-specific inactivation (E7.5–E9.5), NCC lineage tracing, comparative RNA-seq, extracellular matrix analysis","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with stage-specific requirement, RNA-seq pathway analysis, and ECM characterization; preprint not yet peer-reviewed","pmids":["39896510"],"is_preprint":true}],"current_model":"RDH10 (SDR16C4) is a membrane-associated, strictly NAD+-dependent short-chain dehydrogenase/reductase that catalyzes the first oxidative step of vitamin A metabolism — converting retinol to retinaldehyde — with exceptionally high affinity for all-trans-retinol; it localizes to mitochondria/MAM under basal conditions and redistributes to lipid droplets during acyl ester biosynthesis, functions as the primary enzyme driving embryonic all-trans-retinoic acid synthesis, acts as an 11-cis-retinol dehydrogenase in the visual cycle through physical interaction with CRALBP and RPE65, operates within a PPARγ-regulated RDH10–RALDH2–CRABP2 linear pathway in dendritic cells, and is required for a broad range of developmental processes including craniofacial morphogenesis, limb interdigital regression, salivary gland initiation, palate formation via fetal mouth movement, ENS formation via regulation of the NCC microenvironment, and adipogenesis/metabolic homeostasis in postnatal life."},"narrative":{"mechanistic_narrative":"RDH10 is a membrane-associated short-chain dehydrogenase that catalyzes the first oxidative step of vitamin A metabolism, converting retinol to retinaldehyde and thereby driving retinoic acid (RA) synthesis required across embryonic and postnatal development [PMID:17473173, PMID:18502750]. Biochemically it is strictly NAD+-dependent with an exceptionally low Km for all-trans-retinol (~0.035 µM), acts exclusively in the oxidative direction in cells, and is the rate-limiting source of retinaldehyde feeding RA production [PMID:18502750]; this activity is partitioned into a membrane-bound compartment that shields the reaction from inhibition by cytosolic CRBP1, making cytosolic RDH activity dispensable under normal conditions [PMID:21782811]. The enzyme relocates dynamically between mitochondria/mitochondrial-associated membranes and lipid droplets depending on acyl ester biosynthesis, with distinct N- and C-terminal hydrophobic determinants governing each targeting outcome [PMID:23155051]. In the retina, RDH10 additionally oxidizes 11-cis-retinol within a reconstituted visual cycle and physically interacts with CRALBP and RPE65 [PMID:19458327]. Loss-of-function genetics establish RDH10 as the principal driver of embryonic RA signaling: the trex missense allele abolishes activity and produces craniofacial, limb, and organ defects [PMID:17473173], and tissue- and stage-specific inactivation shows RA generated by RDH10 controls interdigital regression [PMID:21360789], choanae formation [PMID:28169399], salivary gland initiation through RARα and SOX9 [PMID:29986869], palate closure via fetal mouth movement [PMID:31300413], and optic cup formation through the direct RA target Alx1 [PMID:bio_10.1101_2025.06.24.661406]. Postnatally, RDH10 haploinsufficiency lowers atRA in liver and adipose tissue, escalating adipogenesis and producing adiposity, steatosis, and insulin resistance reversible by atRA [PMID:29321172]. In dendritic cells RDH10 operates within a PPARγ-regulated RDH10–RALDH2–CRABP2 pathway for ATRA production [PMID:23833249].","teleology":[{"year":2004,"claim":"First localized RDH10's retinol dehydrogenase activity to microsomal membranes in retinal cells, establishing it as a generator of all-trans retinal feeding downstream photoisomerase activity.","evidence":"IHC, RT-PCR and HPLC-based RDH activity assays on microsomal fractions of Müller (rMC-1) cells","pmids":["15505029"],"confidence":"Medium","gaps":["Reported NADP preference later overturned for the human enzyme","Single-lab study without genetic loss-of-function"]},{"year":2007,"claim":"Defined RDH10 as the enzyme catalyzing the first oxidative step of vitamin A metabolism and demonstrated its requirement for embryonic RA signaling via a loss-of-function allele.","evidence":"ENU forward genetic screen yielding the trex missense allele, enzymatic assays, and mutant embryo phenotyping","pmids":["17473173"],"confidence":"High","gaps":["Cofactor identity not yet resolved at this stage","Subcellular site of catalysis not defined"]},{"year":2007,"claim":"Linked RDH10-driven RA production to growth control by showing overexpression raises RA and arrests hepatocellular carcinoma cell proliferation.","evidence":"Stable RDH10 overexpression in HepG2 cells with RARE-CAT reporter, proliferation assays, and cell-cycle gene RT-PCR","pmids":["17218779"],"confidence":"Low","gaps":["Single overexpression experiment with indirect RA readout","No endogenous loss-of-function in tumor context","Mechanism of antiproliferative effect inferred only from mRNA changes"]},{"year":2008,"claim":"Resolved the enzymology: RDH10 is strictly NAD+-dependent with very high affinity for all-trans-retinol and functions only in the oxidative direction, correcting the earlier NADP+ assignment.","evidence":"Kinetic assays with purified recombinant enzyme, cofactor specificity tests, and siRNA knockdown with retinoid quantification in human cells","pmids":["18502750"],"confidence":"High","gaps":["No crystal structure or active-site model","Membrane topology not defined"]},{"year":2009,"claim":"Extended RDH10's role into the visual cycle, showing it oxidizes 11-cis-retinol and physically partners with CRALBP and RPE65.","evidence":"In vitro 11-cis-RDH assay, reconstituted visual cycle in HEK-293A cells, co-immunoprecipitation, and IHC in bovine RPE","pmids":["19458327"],"confidence":"High","gaps":["Physiological contribution to the visual cycle in vivo not established","Co-IP not reciprocally validated for direct binding"]},{"year":2011,"claim":"Established that the rate-limiting retinol oxidation occurs in a membrane compartment, explaining why the reaction escapes CRBP1 inhibition and why cytosolic RDHs are dispensable.","evidence":"Rdh10trex embryos, membrane vs cytosolic RDH activity assays, and dietary retinaldehyde rescue","pmids":["21782811"],"confidence":"High","gaps":["Exact membrane identity not pinned in this study","Does not address tissue-specific enzyme redundancy"]},{"year":2011,"claim":"Dissected the developmental specificity of RDH10-dependent RA, showing it drives interdigital regression but is not required for limb skeletal patterning.","evidence":"RARE-lacZ reporter, exogenous RA rescue, skeletal staining and in situ hybridization in Rdh10trex mutants","pmids":["21360789"],"confidence":"High","gaps":["Source of residual patterning RA in mutant limb unresolved","Cellular mechanism of interdigital cell loss not detailed"]},{"year":2012,"claim":"Revealed dynamic subcellular partitioning of RDH10 between mitochondria/MAM and lipid droplets and mapped the N- and C-terminal determinants of targeting.","evidence":"Subcellular fractionation, domain deletion mutants, and fluorescence colocalization with CRBP1 and LRAT","pmids":["23155051"],"confidence":"Medium","gaps":["Proposed retinol metabolon not biochemically reconstituted","Functional consequence of relocation for RA output not measured","Single-lab cell biology study"]},{"year":2013,"claim":"Placed RDH10 within a defined PPARγ-regulated linear ATRA-synthesis pathway in dendritic cells alongside RALDH2 and CRABP2.","evidence":"siRNA knockdown of RDH10, RALDH2 and CRABP2 in human mo-DCs with ATRA measurement and PPARγ activation assays","pmids":["23833249"],"confidence":"Medium","gaps":["Direct transcriptional regulation of RDH10 by PPARγ not shown at promoter level","In vivo immune consequence not tested"]},{"year":2017,"claim":"Defined a cell-type- and stage-specific requirement for RDH10 in non-neural-crest cells for choanae formation, linking RA loss to ectopic Fgf8 and epithelial defects.","evidence":"Conditional/temporal Rdh10 mutants, lineage tracing, Fgf8 in situ, and proliferation/apoptosis assays","pmids":["28169399"],"confidence":"Medium","gaps":["Direct RA target genes in nasal epithelium not identified","Single-lab study"]},{"year":2018,"claim":"Demonstrated a postnatal metabolic role: RDH10 haploinsufficiency lowers atRA and escalates adipogenesis, adiposity and insulin resistance, reversible by atRA.","evidence":"Rdh10 heterozygote and knockout mice, LC-MS atRA quantification, adipogenesis assays, metabolic phenotyping, and pharmacological rescue","pmids":["29321172"],"confidence":"High","gaps":["Tissue-autonomous vs systemic contribution not fully separated","RAR target genes in adipocytes not enumerated"]},{"year":2018,"claim":"Showed RDH10-derived RA acts specifically through RARα to drive SOX9 expression and epithelial invagination in salivary gland initiation.","evidence":"Ex vivo salivary gland initiation assay, stage-specific Rdh10 inactivation, and RAR isoform-specific inhibitors/agonists","pmids":["29986869"],"confidence":"Medium","gaps":["Direct RARα target genes upstream of SOX9 not defined","Single-lab ex vivo system"]},{"year":2019,"claim":"Uncovered a mechanical mechanism for RDH10-dependent palate closure, where RA-dependent pharyngeal patterning enables fetal mouth movement required for shelf elevation.","evidence":"Stage-specific Rdh10 inactivation, X-ray microtomography, in utero ultrasound, and tissue staining of nerves and skeletal elements","pmids":["31300413"],"confidence":"Medium","gaps":["Molecular RA targets in pharyngeal nerve/skeletal patterning not identified","Single-lab study"]},{"year":2025,"claim":"Identified Alx1 as a direct RA target downstream of RDH10 in optic cup formation, providing a molecular effector for an RDH10-dependent developmental phenotype.","evidence":"Rdh10 KO mouse with H3K27ac ChIP-seq, RNA-seq, RARE mapping, and CRISPR Alx1 knockout phenocopy (preprint)","pmids":["bio_10.1101_2025.06.24.661406"],"confidence":"Medium","gaps":["Preprint not yet peer-reviewed","Direct RARE occupancy not validated by reporter assay"]},{"year":2025,"claim":"Established a requirement for RDH10 in the foregut mesenchymal microenvironment for vagal neural crest invasion, linking RA loss to Ret-Gdnf-Gfrα1 signaling and ECM changes underlying enteric aganglionosis.","evidence":"Stage-specific Rdh10 loss-of-function mice, NCC lineage tracing, RNA-seq, and ECM analysis (preprint)","pmids":["39896510"],"confidence":"Medium","gaps":["Preprint not yet peer-reviewed","Direct RA-responsive elements in Ret-Gdnf network not mapped","Causality of ECM changes vs signaling not separated"]},{"year":null,"claim":"How RDH10's dynamic membrane localization, cofactor handling, and physical interactions are mechanistically coupled to control RA output in different tissues remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the enzyme or its membrane topology","The proposed lipid-droplet retinol metabolon is not biochemically reconstituted","Tissue-specific partner sets directing RDH10 output are uncharacterized"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[0,2,3]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[6]},{"term_id":"GO:0005811","term_label":"lipid droplet","supporting_discovery_ids":[6]},{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[1,4]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,2,9]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[0,5,8,10,11]},{"term_id":"R-HSA-9709957","term_label":"Sensory Perception","supporting_discovery_ids":[3]}],"complexes":[],"partners":["CRALBP","RPE65","RALDH2","CRABP2","CRBP1","LRAT"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8IZV5","full_name":"Retinol dehydrogenase 10","aliases":["Short chain dehydrogenase/reductase family 16C member 4"],"length_aa":341,"mass_kda":38.1,"function":"Retinol dehydrogenase with a clear preference for NADP. Converts all-trans-retinol to all-trans-retinal. Has no detectable activity towards 11-cis-retinol, 9-cis-retinol and 13-cis-retinol","subcellular_location":"Microsome membrane; Endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/Q8IZV5/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RDH10","classification":"Not Classified","n_dependent_lines":41,"n_total_lines":1208,"dependency_fraction":0.03394039735099338},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/RDH10","total_profiled":1310},"omim":[{"mim_id":"607599","title":"RETINOL DEHYDROGENASE 10; RDH10","url":"https://www.omim.org/entry/607599"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Lipid droplets","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/RDH10"},"hgnc":{"alias_symbol":["SDR16C4"],"prev_symbol":[]},"alphafold":{"accession":"Q8IZV5","domains":[{"cath_id":"3.40.50.720","chopping":"32-338","consensus_level":"high","plddt":91.8278,"start":32,"end":338}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8IZV5","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8IZV5-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8IZV5-F1-predicted_aligned_error_v6.png","plddt_mean":91.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RDH10","jax_strain_url":"https://www.jax.org/strain/search?query=RDH10"},"sequence":{"accession":"Q8IZV5","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8IZV5.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8IZV5/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8IZV5"}},"corpus_meta":[{"pmid":"17473173","id":"PMC_17473173","title":"RDH10 is essential for synthesis of embryonic retinoic acid and is required for limb, craniofacial, and organ development.","date":"2007","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/17473173","citation_count":276,"is_preprint":false},{"pmid":"21782811","id":"PMC_21782811","title":"RDH10 is the primary enzyme responsible for the first step of embryonic Vitamin A metabolism and retinoic acid synthesis.","date":"2011","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/21782811","citation_count":63,"is_preprint":false},{"pmid":"15505029","id":"PMC_15505029","title":"Identification of RDH10, an All-trans Retinol Dehydrogenase, in Retinal Muller Cells.","date":"2004","source":"Investigative ophthalmology & visual science","url":"https://pubmed.ncbi.nlm.nih.gov/15505029","citation_count":60,"is_preprint":false},{"pmid":"18502750","id":"PMC_18502750","title":"Kinetic analysis of human enzyme RDH10 defines the characteristics of a physiologically relevant retinol dehydrogenase.","date":"2008","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/18502750","citation_count":57,"is_preprint":false},{"pmid":"19458327","id":"PMC_19458327","title":"The 11-cis-retinol dehydrogenase activity of RDH10 and its interaction with visual cycle proteins.","date":"2009","source":"Investigative ophthalmology & visual science","url":"https://pubmed.ncbi.nlm.nih.gov/19458327","citation_count":57,"is_preprint":false},{"pmid":"21360789","id":"PMC_21360789","title":"Rdh10 mutants deficient in limb field retinoic acid signaling exhibit normal limb patterning but display interdigital webbing.","date":"2011","source":"Developmental dynamics : an official publication of the American Association of Anatomists","url":"https://pubmed.ncbi.nlm.nih.gov/21360789","citation_count":53,"is_preprint":false},{"pmid":"17849458","id":"PMC_17849458","title":"Expression of the murine retinol dehydrogenase 10 (Rdh10) gene correlates with many sites of retinoid signalling during embryogenesis and organ differentiation.","date":"2007","source":"Developmental dynamics : an official publication of the American Association of Anatomists","url":"https://pubmed.ncbi.nlm.nih.gov/17849458","citation_count":48,"is_preprint":false},{"pmid":"29321172","id":"PMC_29321172","title":"Modest Decreases in Endogenous All-trans-Retinoic Acid Produced by a Mouse Rdh10 Heterozygote Provoke Major Abnormalities in Adipogenesis and Lipid Metabolism.","date":"2018","source":"Diabetes","url":"https://pubmed.ncbi.nlm.nih.gov/29321172","citation_count":42,"is_preprint":false},{"pmid":"23155051","id":"PMC_23155051","title":"The retinol dehydrogenase Rdh10 localizes to lipid droplets during acyl ester biosynthesis.","date":"2012","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23155051","citation_count":41,"is_preprint":false},{"pmid":"22162152","id":"PMC_22162152","title":"Morphological defects in a novel Rdh10 mutant that has reduced retinoic acid biosynthesis and signaling.","date":"2012","source":"Genesis (New York, N.Y. : 2000)","url":"https://pubmed.ncbi.nlm.nih.gov/22162152","citation_count":36,"is_preprint":false},{"pmid":"18399539","id":"PMC_18399539","title":"Dynamic expression of the retinoic acid-synthesizing enzyme retinol dehydrogenase 10 (rdh10) in the developing mouse brain and sensory organs.","date":"2008","source":"The Journal of comparative neurology","url":"https://pubmed.ncbi.nlm.nih.gov/18399539","citation_count":32,"is_preprint":false},{"pmid":"28169399","id":"PMC_28169399","title":"Rdh10 loss-of-function and perturbed retinoid signaling underlies the etiology of choanal atresia.","date":"2017","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/28169399","citation_count":26,"is_preprint":false},{"pmid":"23833249","id":"PMC_23833249","title":"RDH10, RALDH2, and CRABP2 are required components of PPARγ-directed ATRA synthesis and signaling in human dendritic cells.","date":"2013","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/23833249","citation_count":24,"is_preprint":false},{"pmid":"20563989","id":"PMC_20563989","title":"The expression of Stra6 and Rdh10 in the avian embryo and their contribution to the generation of retinoid signatures.","date":"2010","source":"The International journal of developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/20563989","citation_count":20,"is_preprint":false},{"pmid":"29986869","id":"PMC_29986869","title":"RDH10-mediated retinol metabolism and RARα-mediated retinoic acid signaling are required for submandibular salivary gland initiation.","date":"2018","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/29986869","citation_count":19,"is_preprint":false},{"pmid":"17218779","id":"PMC_17218779","title":"Forced expression of RDH10 gene retards growth of HepG2 cells.","date":"2007","source":"Cancer biology & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/17218779","citation_count":15,"is_preprint":false},{"pmid":"31300413","id":"PMC_31300413","title":"RDH10 function is necessary for spontaneous fetal mouth movement that facilitates palate shelf elevation.","date":"2019","source":"Disease models & mechanisms","url":"https://pubmed.ncbi.nlm.nih.gov/31300413","citation_count":14,"is_preprint":false},{"pmid":"14596915","id":"PMC_14596915","title":"Genomic organization and transcription of the human retinol dehydrogenase 10 (RDH10) gene.","date":"2003","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/14596915","citation_count":9,"is_preprint":false},{"pmid":"39896510","id":"PMC_39896510","title":"Rdh10-mediated Retinoic Acid Signaling Regulates the Neural Crest Cell Microenvironment During ENS Formation.","date":"2025","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/39896510","citation_count":2,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.06.24.661406","title":"Retinoic acid-regulated epigenetic marks identify  <i>Alx1</i>  as a direct target gene required for optic cup formation","date":"2025-06-25","source":"bioRxiv","url":"https://doi.org/10.1101/2025.06.24.661406","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":11744,"output_tokens":4281,"usd":0.049723,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":12247,"output_tokens":4683,"usd":0.089155,"stage2_stop_reason":"end_turn"},"total_usd":0.138878,"stage1_batch_id":"msgbatch_01CNoDbkChHEkgrJnL7BwtGJ","stage2_batch_id":"msgbatch_016Y4x9E9Wg5VQDANj9quSQD","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2007,\n      \"finding\": \"RDH10 catalyzes the first oxidative step of vitamin A metabolism — the oxidation of retinol to retinal — and is required for embryonic retinoic acid synthesis. A missense mutation in RDH10 (trex allele) abolishes this retinol dehydrogenase activity, resulting in insufficient RA signaling and craniofacial, limb, and organ defects.\",\n      \"method\": \"ENU forward genetic screen, protein modeling, enzymatic activity assays, and analysis of mutant embryos\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — enzymatic assays combined with mutagenesis and in vivo genetic model, replicated across multiple subsequent studies\",\n      \"pmids\": [\"17473173\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"RDH10 is expressed in retinal Müller cells (in addition to RPE) and its all-trans retinol dehydrogenase activity localizes to the microsomal fraction, using NADP as a preferred cofactor in those cells. It generates all-trans retinal, which serves as substrate for the photoisomerase RGR in Müller cells.\",\n      \"method\": \"Western blot, immunohistochemistry, RT-PCR, HPLC-based retinol dehydrogenase activity assay on microsomal fractions of rMC-1 cells\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (IHC, enzymatic assay, HPLC) in a single lab study\",\n      \"pmids\": [\"15505029\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Human RDH10 is a strictly NAD+-dependent enzyme (not NADP+-dependent as initially reported) with multisubstrate specificity, recognizing both all-trans-retinol and cis-retinols as substrates. It has an exceptionally low apparent Km for all-trans-retinol (~0.035 µM) but a relatively high Km for NAD+ (~100 µM). RDH10 functions exclusively in the oxidative direction in cells, increasing retinaldehyde and retinoic acid levels. siRNA-mediated knockdown of endogenous RDH10 in human cells significantly decreases retinoic acid production from retinol.\",\n      \"method\": \"Kinetic enzymatic assays with purified recombinant enzyme, cofactor specificity assays, siRNA knockdown with retinoid quantification\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — rigorous in vitro kinetic analysis with mutagenesis-level specificity assays plus siRNA functional validation, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"18502750\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"RDH10 oxidizes 11-cis-retinol to 11-cis-retinaldehyde in vitro (11-cis-RDH activity), stimulated by CRALBP. In a reconstituted visual cycle cell culture model (RDH10 + RPE65 + LRAT + CRALBP co-expression), 11-cis-retinaldehyde is generated from all-trans-retinol. RDH10 physically interacts with CRALBP and RPE65 by co-immunoprecipitation and co-localizes with them in bovine RPE cells.\",\n      \"method\": \"In vitro 11-cis-RDH activity assay in COS1 cells, reconstituted visual cycle in HEK-293A cells, co-immunoprecipitation, immunohistochemistry, HPLC retinoid profiling\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — reconstitution of visual cycle pathway, co-IP for physical interaction, and in vitro enzymatic assay, multiple orthogonal methods in single study\",\n      \"pmids\": [\"19458327\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"RDH10 is the primary retinol dehydrogenase responsible for the first oxidative step of embryonic vitamin A metabolism. The initial retinol-to-retinal conversion occurs predominantly in a membrane-bound cellular compartment, which prevents inhibition by cytosolic CRBP1 (RBP1). Cytosolic enzymes with RDH activity play a very limited role under normal dietary conditions.\",\n      \"method\": \"Rdh10trex mutant embryos, dietary retinaldehyde supplementation, RDH activity assays on membrane vs. cytosolic fractions\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — genetic loss-of-function model combined with biochemical fractionation and dietary rescue, replicated across labs\",\n      \"pmids\": [\"21782811\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"RDH10 (via RA synthesis) is required for interdigital tissue loss but not for limb patterning per se. In Rdh10trex/trex mutants, RA activity is absent from limb mesoderm but present in neuroectoderm; restoration with 25 nM RA rescues RARE-lacZ activity in limb mesoderm. Meis2 and Shh expression and skeletal patterning are normal in Rdh10 mutant hindlimbs despite absent limb RA.\",\n      \"method\": \"RARE-lacZ RA-reporter transgene, exogenous RA rescue, skeletal staining, in situ hybridization in Rdh10trex/trex mutant embryos\",\n      \"journal\": \"Developmental dynamics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with reporter rescue and skeletal phenotyping, multiple orthogonal readouts\",\n      \"pmids\": [\"21360789\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Rdh10 associates predominantly with mitochondria/mitochondrial-associated membrane (MAM) in the absence of lipid droplet biosynthesis, but relocates to lipid droplets during acyl ester biosynthesis. The 32 N-terminal residues (including a hydrophobic region followed by net positive charge) are required for lipid droplet targeting; both N-terminal and 48 C-terminal hydrophobic residues are required for mitochondria/MAM targeting and/or protein stability. Co-localization of Rdh10, CRBP1, and LRAT on lipid droplets suggests a metabolon for retinol homeostasis.\",\n      \"method\": \"Subcellular fractionation, domain deletion mutants, fluorescence colocalization, cell biology assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain mutagenesis combined with fractionation and colocalization in a single lab study\",\n      \"pmids\": [\"23155051\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"In human monocyte-derived dendritic cells, RDH10, RALDH2, and CRABP2 form a linear PPARγ-regulated pathway required for ATRA production. All three proteins are co-regulated by PPARγ activation and all three are required for ATRA synthesis induced by PPARγ-activating fatty acids.\",\n      \"method\": \"siRNA knockdown of RDH10, RALDH2, and CRABP2 in human mo-DCs with ATRA measurement; PPARγ activation assays; colocalization in gut-associated lymphoid tissue DCs\",\n      \"journal\": \"Journal of lipid research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional knockdown with pathway placement, single lab, multiple components tested\",\n      \"pmids\": [\"23833249\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Rdh10 is specifically required in non-neural crest cells prior to E10.5 for proper choanae formation. Loss of Rdh10 leads to ectopic Fgf8 expression in the nasal fin, decreased cell proliferation, and increased cell death in the nasal cavity epithelium, retarding invagination and causing fully penetrant choanal atresia.\",\n      \"method\": \"Conditional/temporal Rdh10 mutant mouse analysis, cell lineage tracing, in situ hybridization for Fgf8, cell proliferation and apoptosis assays\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-type-specific and stage-specific genetic requirement established with molecular readouts, single lab\",\n      \"pmids\": [\"28169399\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Rdh10 heterozygous hypomorphs produce ~25% less atRA in liver and adipose tissue, leading to escalated adipogenesis, increased adiposity under high-fat diet, liver steatosis, glucose intolerance, and insulin resistance. Embryonic fibroblasts with Rdh10 knockout show decreased atRA biosynthesis and escalated adipogenesis reversible by atRA or RAR pan-agonist treatment.\",\n      \"method\": \"Rdh10 heterozygote and knockout mouse models, atRA quantification by LC-MS, adipogenesis assays, metabolic phenotyping, pharmacological rescue with atRA\",\n      \"journal\": \"Diabetes\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic loss-of-function with biochemical atRA quantification and pharmacological rescue, multiple orthogonal metabolic readouts\",\n      \"pmids\": [\"29321172\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"RDH10-mediated retinol metabolism and RARα-mediated RA signaling are required for submandibular salivary gland initiation. RDH10 and RALDH2 are expressed in the SMG mesenchyme at the initiation site, and ex vivo assays demonstrate that RDH10 and RA are both required for SOX9 expression and epithelial invagination. The RA requirement acts specifically through RARα with no contribution from other RAR isoforms.\",\n      \"method\": \"Ex vivo salivary gland initiation assay, stage-specific Rdh10 inactivation, RAR isoform-specific inhibitors/agonists, in situ hybridization\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ex vivo functional assay combined with genetic loss-of-function and pharmacological RAR isoform dissection, single lab\",\n      \"pmids\": [\"29986869\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"RDH10 function (via RA synthesis) is required for spontaneous fetal mouth movement that facilitates palate shelf elevation. Rdh10-deficient embryos display mispatterned pharyngeal nerves and skeletal elements that physically block fetal mouth movement in utero, causing cleft palate through a mechanical (movement-dependent) mechanism rather than a direct tissue defect in the palate shelf.\",\n      \"method\": \"Stage-specific Rdh10 inactivation, X-ray microtomography, in utero ultrasound video, ex vivo culture, tissue staining of pharyngeal nerves and skeletal elements\",\n      \"journal\": \"Disease models & mechanisms\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct imaging of fetal mouth movement combined with genetic loss-of-function, novel mechanistic pathway placement, single lab\",\n      \"pmids\": [\"31300413\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Forced over-expression of RDH10 in HepG2 hepatocellular carcinoma cells increases endogenous RA concentration (measured by RARE-CAT reporter), causes antiproliferative effects without apoptosis, and is associated with upregulation of RARβ and p21Cip1 and downregulation of CyclinE/CDK2 mRNAs.\",\n      \"method\": \"Stable RDH10 over-expression in HepG2 cells, RARE-CAT reporter assay, RT-PCR for cell cycle gene expression, proliferation assays\",\n      \"journal\": \"Cancer biology & therapy\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single over-expression experiment with indirect RA measurement and mRNA readouts, single lab, single method per endpoint\",\n      \"pmids\": [\"17218779\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Rdh10 knockout embryos fail to form a proper optic cup. Combined ChIP-seq (H3K27ac) and RNA-seq on eye tissue identified Alx1 as a direct RA target gene with an RA response element (RARE) near an RA-regulated H3K27ac mark. CRISPR/Cas9 knockout of Alx1 phenocopies Rdh10 KO in optic cup formation, placing Alx1 downstream of RDH10-mediated RA synthesis in eye development.\",\n      \"method\": \"Rdh10 knockout mouse, ChIP-seq for H3K27ac, RNA-seq on eye tissue, CRISPR/Cas9 Alx1 knockout, in situ hybridization\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis combined with epigenomic (ChIP-seq) and transcriptomic evidence plus CRISPR functional validation, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.06.24.661406\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Rdh10 is highly expressed in the mesenchyme surrounding the entrance to the foregut and is essential between E7.5–E9.5 for vagal neural crest cell invasion into the gut. Rdh10 loss-of-function embryos exhibit intestinal aganglionosis; NCC form and migrate normally but fail to invade the foregut. RNA-seq revealed downregulation of the Ret-Gdnf-Gfrα1 signaling network and altered extracellular matrix (increased collagen deposition) in the NCC microenvironment.\",\n      \"method\": \"Rdh10 loss-of-function mouse, stage-specific inactivation (E7.5–E9.5), NCC lineage tracing, comparative RNA-seq, extracellular matrix analysis\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with stage-specific requirement, RNA-seq pathway analysis, and ECM characterization; preprint not yet peer-reviewed\",\n      \"pmids\": [\"39896510\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"RDH10 (SDR16C4) is a membrane-associated, strictly NAD+-dependent short-chain dehydrogenase/reductase that catalyzes the first oxidative step of vitamin A metabolism — converting retinol to retinaldehyde — with exceptionally high affinity for all-trans-retinol; it localizes to mitochondria/MAM under basal conditions and redistributes to lipid droplets during acyl ester biosynthesis, functions as the primary enzyme driving embryonic all-trans-retinoic acid synthesis, acts as an 11-cis-retinol dehydrogenase in the visual cycle through physical interaction with CRALBP and RPE65, operates within a PPARγ-regulated RDH10–RALDH2–CRABP2 linear pathway in dendritic cells, and is required for a broad range of developmental processes including craniofacial morphogenesis, limb interdigital regression, salivary gland initiation, palate formation via fetal mouth movement, ENS formation via regulation of the NCC microenvironment, and adipogenesis/metabolic homeostasis in postnatal life.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"RDH10 is a membrane-associated short-chain dehydrogenase that catalyzes the first oxidative step of vitamin A metabolism, converting retinol to retinaldehyde and thereby driving retinoic acid (RA) synthesis required across embryonic and postnatal development [#0, #2]. Biochemically it is strictly NAD+-dependent with an exceptionally low Km for all-trans-retinol (~0.035 µM), acts exclusively in the oxidative direction in cells, and is the rate-limiting source of retinaldehyde feeding RA production [#2]; this activity is partitioned into a membrane-bound compartment that shields the reaction from inhibition by cytosolic CRBP1, making cytosolic RDH activity dispensable under normal conditions [#4]. The enzyme relocates dynamically between mitochondria/mitochondrial-associated membranes and lipid droplets depending on acyl ester biosynthesis, with distinct N- and C-terminal hydrophobic determinants governing each targeting outcome [#6]. In the retina, RDH10 additionally oxidizes 11-cis-retinol within a reconstituted visual cycle and physically interacts with CRALBP and RPE65 [#3]. Loss-of-function genetics establish RDH10 as the principal driver of embryonic RA signaling: the trex missense allele abolishes activity and produces craniofacial, limb, and organ defects [#0], and tissue- and stage-specific inactivation shows RA generated by RDH10 controls interdigital regression [#5], choanae formation [#8], salivary gland initiation through RARα and SOX9 [#10], palate closure via fetal mouth movement [#11], and optic cup formation through the direct RA target Alx1 [#13]. Postnatally, RDH10 haploinsufficiency lowers atRA in liver and adipose tissue, escalating adipogenesis and producing adiposity, steatosis, and insulin resistance reversible by atRA [#9]. In dendritic cells RDH10 operates within a PPARγ-regulated RDH10–RALDH2–CRABP2 pathway for ATRA production [#7].\",\n  \"teleology\": [\n    {\n      \"year\": 2004,\n      \"claim\": \"First localized RDH10's retinol dehydrogenase activity to microsomal membranes in retinal cells, establishing it as a generator of all-trans retinal feeding downstream photoisomerase activity.\",\n      \"evidence\": \"IHC, RT-PCR and HPLC-based RDH activity assays on microsomal fractions of Müller (rMC-1) cells\",\n      \"pmids\": [\"15505029\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Reported NADP preference later overturned for the human enzyme\", \"Single-lab study without genetic loss-of-function\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined RDH10 as the enzyme catalyzing the first oxidative step of vitamin A metabolism and demonstrated its requirement for embryonic RA signaling via a loss-of-function allele.\",\n      \"evidence\": \"ENU forward genetic screen yielding the trex missense allele, enzymatic assays, and mutant embryo phenotyping\",\n      \"pmids\": [\"17473173\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Cofactor identity not yet resolved at this stage\", \"Subcellular site of catalysis not defined\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Linked RDH10-driven RA production to growth control by showing overexpression raises RA and arrests hepatocellular carcinoma cell proliferation.\",\n      \"evidence\": \"Stable RDH10 overexpression in HepG2 cells with RARE-CAT reporter, proliferation assays, and cell-cycle gene RT-PCR\",\n      \"pmids\": [\"17218779\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single overexpression experiment with indirect RA readout\", \"No endogenous loss-of-function in tumor context\", \"Mechanism of antiproliferative effect inferred only from mRNA changes\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Resolved the enzymology: RDH10 is strictly NAD+-dependent with very high affinity for all-trans-retinol and functions only in the oxidative direction, correcting the earlier NADP+ assignment.\",\n      \"evidence\": \"Kinetic assays with purified recombinant enzyme, cofactor specificity tests, and siRNA knockdown with retinoid quantification in human cells\",\n      \"pmids\": [\"18502750\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No crystal structure or active-site model\", \"Membrane topology not defined\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Extended RDH10's role into the visual cycle, showing it oxidizes 11-cis-retinol and physically partners with CRALBP and RPE65.\",\n      \"evidence\": \"In vitro 11-cis-RDH assay, reconstituted visual cycle in HEK-293A cells, co-immunoprecipitation, and IHC in bovine RPE\",\n      \"pmids\": [\"19458327\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological contribution to the visual cycle in vivo not established\", \"Co-IP not reciprocally validated for direct binding\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Established that the rate-limiting retinol oxidation occurs in a membrane compartment, explaining why the reaction escapes CRBP1 inhibition and why cytosolic RDHs are dispensable.\",\n      \"evidence\": \"Rdh10trex embryos, membrane vs cytosolic RDH activity assays, and dietary retinaldehyde rescue\",\n      \"pmids\": [\"21782811\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Exact membrane identity not pinned in this study\", \"Does not address tissue-specific enzyme redundancy\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Dissected the developmental specificity of RDH10-dependent RA, showing it drives interdigital regression but is not required for limb skeletal patterning.\",\n      \"evidence\": \"RARE-lacZ reporter, exogenous RA rescue, skeletal staining and in situ hybridization in Rdh10trex mutants\",\n      \"pmids\": [\"21360789\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Source of residual patterning RA in mutant limb unresolved\", \"Cellular mechanism of interdigital cell loss not detailed\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Revealed dynamic subcellular partitioning of RDH10 between mitochondria/MAM and lipid droplets and mapped the N- and C-terminal determinants of targeting.\",\n      \"evidence\": \"Subcellular fractionation, domain deletion mutants, and fluorescence colocalization with CRBP1 and LRAT\",\n      \"pmids\": [\"23155051\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Proposed retinol metabolon not biochemically reconstituted\", \"Functional consequence of relocation for RA output not measured\", \"Single-lab cell biology study\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Placed RDH10 within a defined PPARγ-regulated linear ATRA-synthesis pathway in dendritic cells alongside RALDH2 and CRABP2.\",\n      \"evidence\": \"siRNA knockdown of RDH10, RALDH2 and CRABP2 in human mo-DCs with ATRA measurement and PPARγ activation assays\",\n      \"pmids\": [\"23833249\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct transcriptional regulation of RDH10 by PPARγ not shown at promoter level\", \"In vivo immune consequence not tested\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Defined a cell-type- and stage-specific requirement for RDH10 in non-neural-crest cells for choanae formation, linking RA loss to ectopic Fgf8 and epithelial defects.\",\n      \"evidence\": \"Conditional/temporal Rdh10 mutants, lineage tracing, Fgf8 in situ, and proliferation/apoptosis assays\",\n      \"pmids\": [\"28169399\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct RA target genes in nasal epithelium not identified\", \"Single-lab study\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Demonstrated a postnatal metabolic role: RDH10 haploinsufficiency lowers atRA and escalates adipogenesis, adiposity and insulin resistance, reversible by atRA.\",\n      \"evidence\": \"Rdh10 heterozygote and knockout mice, LC-MS atRA quantification, adipogenesis assays, metabolic phenotyping, and pharmacological rescue\",\n      \"pmids\": [\"29321172\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue-autonomous vs systemic contribution not fully separated\", \"RAR target genes in adipocytes not enumerated\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Showed RDH10-derived RA acts specifically through RARα to drive SOX9 expression and epithelial invagination in salivary gland initiation.\",\n      \"evidence\": \"Ex vivo salivary gland initiation assay, stage-specific Rdh10 inactivation, and RAR isoform-specific inhibitors/agonists\",\n      \"pmids\": [\"29986869\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct RARα target genes upstream of SOX9 not defined\", \"Single-lab ex vivo system\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Uncovered a mechanical mechanism for RDH10-dependent palate closure, where RA-dependent pharyngeal patterning enables fetal mouth movement required for shelf elevation.\",\n      \"evidence\": \"Stage-specific Rdh10 inactivation, X-ray microtomography, in utero ultrasound, and tissue staining of nerves and skeletal elements\",\n      \"pmids\": [\"31300413\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular RA targets in pharyngeal nerve/skeletal patterning not identified\", \"Single-lab study\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identified Alx1 as a direct RA target downstream of RDH10 in optic cup formation, providing a molecular effector for an RDH10-dependent developmental phenotype.\",\n      \"evidence\": \"Rdh10 KO mouse with H3K27ac ChIP-seq, RNA-seq, RARE mapping, and CRISPR Alx1 knockout phenocopy (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.06.24.661406\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint not yet peer-reviewed\", \"Direct RARE occupancy not validated by reporter assay\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Established a requirement for RDH10 in the foregut mesenchymal microenvironment for vagal neural crest invasion, linking RA loss to Ret-Gdnf-Gfrα1 signaling and ECM changes underlying enteric aganglionosis.\",\n      \"evidence\": \"Stage-specific Rdh10 loss-of-function mice, NCC lineage tracing, RNA-seq, and ECM analysis (preprint)\",\n      \"pmids\": [\"39896510\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint not yet peer-reviewed\", \"Direct RA-responsive elements in Ret-Gdnf network not mapped\", \"Causality of ECM changes vs signaling not separated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How RDH10's dynamic membrane localization, cofactor handling, and physical interactions are mechanistically coupled to control RA output in different tissues remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the enzyme or its membrane topology\", \"The proposed lipid-droplet retinol metabolon is not biochemically reconstituted\", \"Tissue-specific partner sets directing RDH10 output are uncharacterized\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [0, 2, 3]},\n      {\"term_id\": \"GO:0016209\", \"supporting_discovery_ids\": []}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [6]},\n      {\"term_id\": \"GO:0005811\", \"supporting_discovery_ids\": [6]},\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [1, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 2, 9]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [0, 5, 8, 10, 11]},\n      {\"term_id\": \"R-HSA-9709957\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"CRALBP\", \"RPE65\", \"RALDH2\", \"CRABP2\", \"CRBP1\", \"LRAT\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}