| Structural highlights
2zk4 is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: |
| | Related: | 2zk0, 2zk1, 2zk2, 2zk3, 2zk5, 2zk6 |
| Gene: | pparg (Homo sapiens) |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Disease
[PPARG_HUMAN] Note=Defects in PPARG can lead to type 2 insulin-resistant diabetes and hyptertension. PPARG mutations may be associated with colon cancer. Defects in PPARG may be associated with susceptibility to obesity (OBESITY) [MIM:601665]. It is a condition characterized by an increase of body weight beyond the limitation of skeletal and physical requirements, as the result of excessive accumulation of body fat.[1] Defects in PPARG are the cause of familial partial lipodystrophy type 3 (FPLD3) [MIM:604367]. Familial partial lipodystrophies (FPLD) are a heterogeneous group of genetic disorders characterized by marked loss of subcutaneous (sc) fat from the extremities. Affected individuals show an increased preponderance of insulin resistance, diabetes mellitus and dyslipidemia.[2] [3] Genetic variations in PPARG can be associated with susceptibility to glioma type 1 (GLM1) [MIM:137800]. Gliomas are central nervous system neoplasms derived from glial cells and comprise astrocytomas, glioblastoma multiforme, oligodendrogliomas, and ependymomas. Note=Polymorphic PPARG alleles have been found to be significantly over-represented among a cohort of American patients with sporadic glioblastoma multiforme suggesting a possible contribution to disease susceptibility.
Function
[PPARG_HUMAN] Receptor that binds peroxisome proliferators such as hypolipidemic drugs and fatty acids. Once activated by a ligand, the receptor binds to a promoter element in the gene for acyl-CoA oxidase and activates its transcription. It therefore controls the peroxisomal beta-oxidation pathway of fatty acids. Key regulator of adipocyte differentiation and glucose homeostasis. Acts as a critical regulator of gut homeostasis by suppressing NF-kappa-B-mediated proinflammatory responses.[4] [5] [6]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Peroxisome proliferator-activated receptor (PPAR) gamma is a nuclear receptor that regulates lipid homeostasis, and several fatty acid metabolites have been identified as PPARgamma ligands. Here, we present four crystal structures of the PPARgamma ligand binding domain (LBD) covalently bound to endogenous fatty acids via a unique cysteine, which is reportedly critical for receptor activation. The structure analyses of the LBD complexed with 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) revealed that the covalent binding of 15d-PGJ(2) induced conformational changes in the loop region following helix H2', and rearrangements of the side-chain network around the created covalent bond in the LBD. Point mutations of these repositioned residues on the loop and helix H3 almost completely abolished PPARgamma activation by 15d-PGJ(2), indicating that the observed structural alteration may be crucial for PPARgamma activation by the endogenous fatty acid. To address the issue of partial agonism of endogenous PPARgamma ligands, we took advantage of a series of oxidized eicosatetraenoic acids (oxoETEs) as covalently bound ligands to PPARgamma. Despite similar structural and chemical properties, these fatty acids exhibited distinct degrees of transcriptional activity. Crystallographic studies, using two of the oxoETE/PPARgamma LBD complexes, revealed that transcriptional strength of each oxoETE is associated with the difference in the loop conformation, rather than the interaction between each ligand and helix H12. These results suggest that the loop conformation may be responsible for the modulation of PPARgamma activity. Based on these results, we identified novel agonists covalently bound to PPARgamma by in silico screening and a cell-based assay. Our crystallographic study of LBD complexed with nitro-233 demonstrated that the expected covalent bond is indeed formed between this newly identified agonist and the cysteine. This study presents the structural basis for the activation and modulation mechanism of PPARgamma through covalent modification with endogenous fatty acids.
Structural insight into PPARgamma activation through covalent modification with endogenous fatty acids.,Waku T, Shiraki T, Oyama T, Fujimoto Y, Maebara K, Kamiya N, Jingami H, Morikawa K J Mol Biol. 2009 Jan 9;385(1):188-99. Epub 2008 Oct 19. PMID:18977231[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Ristow M, Muller-Wieland D, Pfeiffer A, Krone W, Kahn CR. Obesity associated with a mutation in a genetic regulator of adipocyte differentiation. N Engl J Med. 1998 Oct 1;339(14):953-9. PMID:9753710 doi:10.1056/NEJM199810013391403
- ↑ Hegele RA, Cao H, Frankowski C, Mathews ST, Leff T. PPARG F388L, a transactivation-deficient mutant, in familial partial lipodystrophy. Diabetes. 2002 Dec;51(12):3586-90. PMID:12453919
- ↑ Agarwal AK, Garg A. A novel heterozygous mutation in peroxisome proliferator-activated receptor-gamma gene in a patient with familial partial lipodystrophy. J Clin Endocrinol Metab. 2002 Jan;87(1):408-11. PMID:11788685
- ↑ Mukherjee R, Jow L, Croston GE, Paterniti JR Jr. Identification, characterization, and tissue distribution of human peroxisome proliferator-activated receptor (PPAR) isoforms PPARgamma2 versus PPARgamma1 and activation with retinoid X receptor agonists and antagonists. J Biol Chem. 1997 Mar 21;272(12):8071-6. PMID:9065481
- ↑ Yin Y, Yuan H, Wang C, Pattabiraman N, Rao M, Pestell RG, Glazer RI. 3-phosphoinositide-dependent protein kinase-1 activates the peroxisome proliferator-activated receptor-gamma and promotes adipocyte differentiation. Mol Endocrinol. 2006 Feb;20(2):268-78. Epub 2005 Sep 8. PMID:16150867 doi:10.1210/me.2005-0197
- ↑ Park SH, Choi HJ, Yang H, Do KH, Kim J, Lee DW, Moon Y. Endoplasmic reticulum stress-activated C/EBP homologous protein enhances nuclear factor-kappaB signals via repression of peroxisome proliferator-activated receptor gamma. J Biol Chem. 2010 Nov 12;285(46):35330-9. doi: 10.1074/jbc.M110.136259. Epub 2010, Sep 9. PMID:20829347 doi:10.1074/jbc.M110.136259
- ↑ Waku T, Shiraki T, Oyama T, Fujimoto Y, Maebara K, Kamiya N, Jingami H, Morikawa K. Structural insight into PPARgamma activation through covalent modification with endogenous fatty acids. J Mol Biol. 2009 Jan 9;385(1):188-99. Epub 2008 Oct 19. PMID:18977231 doi:10.1016/j.jmb.2008.10.039
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