Receptor nomenclature | NR1C3 |
Receptor code | 4.10.1:FA:1:C3 |
Molecular information | Hs: 478aa, P37231, chr. 3p251–3 |
| Rn: 505aa, O88275, chr. 4q424 |
| Mm: 475aa, P37238, chr. 6 E3-F15 |
DNA binding | |
Structure | Heterodimer, RXR partner |
HRE core sequence | AACTAGGNCA A AGGTCA (DR-1) |
Partners | RXR (physical, functional) DNA binding6 |
Agonists | SB-219994 (8.68), LY-510929 (8), AD-5061 (7.7), TZD18 (7.24), L-764406 (7.15), ragaglitazar (7.03), GW0072 (6.96), nTzDpa (6.5), troglitazone (6.27), LY-465608 (6.26), pioglitazone (6.23), fatty acids (6), SB-219993 (5.5), 5-ASA (1.82) [pIC50]7–26. GW1929 (8.84), L-796449 (8.7), GW7845 (8.43), CDDO (8), L-783483 (7.85), L-165461 (7.8), AD5075 (7.66), [3H]AD5075* (7.66), FMOC-l-leucine (∼6), CS-045 (5.8) [pKi]27–32. [3H]AD-5061* (8), farglitazar (7.47), indomethacin (7.38), rosiglitazone* (7.37), [125I]SB-236636* (7.1), [3H]GW2331* (6.52), GW2331 (6.52), KRP-297/MK-0767 (6.49), PAT5A (6.35), MCC555 (∼6.3), Iinoleic acid (5.3), BADGE (4) [pKd]13,15, 34,21,22 ,26,33–43. GW409544 (9.55), GW9578 (6) BVT0.13 (7.52), TAK-559 (7.5), reglitazar (7.08), GW9578 (6), ciglitazone (4.64), KRP-297/MK-0767 (7) [pEC50]13,22,44–49; DRF2519, LG10074, ibuprofen, diclofenac, COOH50–56 |
Antagonists | GW9662 (8.48), PD068235 (6.1), BADGE (5), SR-202 (3.85) [pIC50]57–59, 42; CDDO-Me (8), LG100641 (6.36) [pKi]32,60; diclofenac55 |
Coactivators | PGC-2, ARA-70, PGC-1α, PPARGC1B, CREBBP, p300, CITED2, ERAP140, PPARBP, PRMT-2, PIMT, NCOA1, NCOA2, NCOA3, NCOA6, SWI/SNF, PDIP61–76,80–88,137 |
Corepressors | NRIP1, SAF-B, TAZ, NCOR1, NCOR268,89–94 |
Biologically important isoforms | PPARγ1 {Hs, Mm}: encoded by eight exons (two of them PPARγ1-specific)2,95,96; PPARγ2 {Hs, Mm, Rn}: N terminus carries 30 additional amino acids encoded by exon B PPARγ2-specific, encoded by seven exons2,95; PPARγ3 {Hs}: gives rise to a protein indistinguishable from PPARγ1 from a distinct promoter—expression restricted to the colon and adipose tissue97; γORF4 {Hs}: read-through in intron 4, encoded protein lacks the LBD, dominant-negative vs. PPARγ, expressed in tumor cell lines and tissues3 |
Tissue distribution | Adipose tissues, lymphoid tissues, colon, liver, and heart {Hs, Mm, Rn} [Northern blot, Western blot, immunohistology]90 |
Functional assays | BADGE adipogenesis assay using 3T3-L1 and 3T3-F442A cells {Mm}42; induction of apoptotic cell death by measuring lipogenesis in C6 glioma cells {Rn}98; measurement of lipogenesis in C3H10T1/2 cells to determine adipocyte differentiation {Hs}29,35 |
Main target genes | Activated: FATP {Mm}99, acyl CoA-synthetase {Mm}100,101, aP2 adipocyte lipid-binding protein {Mm}102, Lpl {Mm}103, UCP-1 {Mm}104,105, PEPCK {Mm}106, Apoa2 {Mm}107 |
Mutant phenotype | Forced expression in hepatocytes induced the classic pattern of PPARγ-mediated gene activation and resulted in steatosis {Mm} [retroviral infection]108; disrupted expression in macrophages {Mm} [transgenesis]109; knockout not viable due to defects in placenta formation {Mm} [knockout]110; conditional knockout in adipocytes causes white and brown adipocytes to be replaced with newly formed PPARγ-positive adipocytes {Mm} [conditional knockout]111; conditional knockout in adipocytes results in lipodystrophy (hypocellularity and hypertrophy), elevated plasma FFAs and TGs, decreased plasma leptin and adiponectin, and insuline resistance in fat and liver {Mm} [conditional knockout]112; conditional knockout in white adipocytes results in retarded growth, severe lipodystrophy (hypocellularity and hypertrophy) and hyperlipidemia {Mm} [conditional knockout]113; conditional knockout in muscle causes progressive insulin resistance combined with increased adipose tissue mass {Mm} [conditional knockout]114,115; conditional knockout in pancreatic β-cells results in significant islet hyperplasia on chow diet, blunted expansion of β-cell mass {Mm} [conditional knockout]116; L466A dominant-negative knockin mutant {Mm} [knockin]117; heterozygous mice have reduced body size and weight, reduced insulin resistance, smaller adipocytes and fat depots {Mm} [knockout]54,118,119 |
Human disease | Obesity and insulin resistance: associated with a mutation in the ligand-independent activation domain of PPARγ2—increased PPARγ2 mRNA found in obese subjects120–124; insulin resistance, type II diabetes mellitus and hypertension: associated with a mutation of the LBD—improved insulin sensitivity associated with polymorphism (Pro12Ala) in PPARγ246,121,123,125,126; syndrome X or metabolic syndrome: associated with dominant-negative PPARγ mutations125–127; atherosclerosis: increased receptor expression in atherosclerotic lesions, macrophages, and monocytic cell lines123,128; colon cancer: associated with loss-of-function mutations in PPARγ LBD—potential antitumor efficacy of combining RXR and PPARγ agonist129–132; prostate cancer: PPARγ expressed in human prostate adenocarcinomas and cell lines derived from human prostate tumors133; thyroid tumors: the PAX8-PPARγ fusion protein promotes differentiated follicular thyroid neoplasia134–136 |