Structural highlights
Function
[URE2_YEAST] Plays an important role in nitrogen catabolite repression. Down-regulates the expression of many genes involved in nitrogen utilization by inhibiting the GATA transcriptional activators GLN3 and GAT1. Under good nitrogen conditions, binds to the phosphorylated forms of GLN3 and GAT1 and sequesters them in the cytoplasm, preventing transcription of genes expressed upon nitrogen limitation. Is also an atypical glutaredoxin without a catalytical cysteine residue. Has glutathione peroxidase and thiol:disulfide oxidoreductase activities in both native and fibrillar form. Also shows insulin disulfide reductase and dehydroascorbic acid reductase (DHAR) actvites.[1] [2] [3] [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
The [URE3] phenotype in yeast Saccharomyces cerevisiae is due to an altered prion form of Ure2p, a protein involved in nitrogen catabolism. To understand possible conformational changes at the origin of prion propagation, we previously solved the crystal structure of the Ure2p functional region [Bousset et al. (2001) Structure 9, 39-46]. We showed the protein to have a fold similar to that of the beta class of glutathione S-transferases (GSTs). Here we report crystal structures of the Ure2p functional region (extending from residues 95-354) in complex with glutathione (GSH), the substrate of all GSTs, and two widely used GST inhibitors, namely, S-hexylglutathione and S-p-nitrobenzylglutathione. In a manner similar to what is observed in many GSTs, ligand binding is not accompanied by a significant change in the conformation of the protein. We identify one GSH and one hydrophobic electrophile binding site per monomer as observed in all other GSTs. The sulfur group of GSH, that conjugates electrophiles, is located near the amide group of Asn124, allowing a hydrogen bond to be formed. Biochemical data indicate that GSH binds to Ure2p with high affinity. Its binding affects Ure2p oligomerization but has no effect on the assembly of the protein into amyloid fibrils. Despite results indicating that Ure2p lacks GST activity, we propose that Ure2p is a member of the GST superfamily that may describe a novel GST class. Our data bring new insights into the function of the Ure2p active region.
Crystal structures of the yeast prion Ure2p functional region in complex with glutathione and related compounds.,Bousset L, Belrhali H, Melki R, Morera S Biochemistry. 2001 Nov 13;40(45):13564-73. PMID:11695904[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Coschigano PW, Magasanik B. The URE2 gene product of Saccharomyces cerevisiae plays an important role in the cellular response to the nitrogen source and has homology to glutathione s-transferases. Mol Cell Biol. 1991 Feb;11(2):822-32. PMID:1990286
- ↑ Blinder D, Coschigano PW, Magasanik B. Interaction of the GATA factor Gln3p with the nitrogen regulator Ure2p in Saccharomyces cerevisiae. J Bacteriol. 1996 Aug;178(15):4734-6. PMID:8755910
- ↑ Beck T, Hall MN. The TOR signalling pathway controls nuclear localization of nutrient-regulated transcription factors. Nature. 1999 Dec 9;402(6762):689-92. PMID:10604478 doi:http://dx.doi.org/10.1038/45287
- ↑ Cunningham TS, Andhare R, Cooper TG. Nitrogen catabolite repression of DAL80 expression depends on the relative levels of Gat1p and Ure2p production in Saccharomyces cerevisiae. J Biol Chem. 2000 May 12;275(19):14408-14. PMID:10799523
- ↑ Bai M, Zhou JM, Perrett S. The yeast prion protein Ure2 shows glutathione peroxidase activity in both native and fibrillar forms. J Biol Chem. 2004 Nov 26;279(48):50025-30. Epub 2004 Sep 15. PMID:15371425 doi:http://dx.doi.org/10.1074/jbc.M406612200
- ↑ Zhang ZR, Perrett S. Novel glutaredoxin activity of the yeast prion protein Ure2 reveals a native-like dimer within fibrils. J Biol Chem. 2009 May 22;284(21):14058-67. doi: 10.1074/jbc.M901189200. Epub 2009, Mar 25. PMID:19321443 doi:http://dx.doi.org/10.1074/jbc.M901189200
- ↑ Bousset L, Belrhali H, Melki R, Morera S. Crystal structures of the yeast prion Ure2p functional region in complex with glutathione and related compounds. Biochemistry. 2001 Nov 13;40(45):13564-73. PMID:11695904
