3olm

Structural highlights

Function

[RSP5_YEAST] E3 ubiquitin-protein ligase which accepts ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. Component of a RSP5 ubiquitin ligase complex which specifies polyubiquitination and intracellular trafficking of the general amino acid permease GAP1 as well as other cell surface proteins like GAP1, FUR4, MAL61, PMA1 and STE2. The RSP5-BUL1/2 complex is also necessary for the heat-shock element (HSE)-mediated gene expression, nitrogen starvation GLN3-dependent transcription, pressure-induced differential regulation of the two tryptophan permeases TAT1 and TAT2 and sorting efficiency into multivesicular bodies. Also acts on RBP1. Plays a role in tolerance to o-dinitrobenzene. Involved in actin cytoskeleton organization and dynamics. Ubiquitinates the LAS17-binding proteins LSB1 and PIN3/LSB2 without directing them for degradation and affects LAS17 levels in a SLA1-dependent and LSB1/2-independent manner.^{[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12]} [UBI4P_YEAST] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity).

See Also

• Ubiquitin protein ligase

References

1. ↑ Huibregtse JM, Scheffner M, Beaudenon S, Howley PM. A family of proteins structurally and functionally related to the E6-AP ubiquitin-protein ligase. Proc Natl Acad Sci U S A. 1995 Mar 28;92(7):2563-7. PMID:7708685
2. ↑ Yashiroda H, Kaida D, Toh-e A, Kikuchi Y. The PY-motif of Bul1 protein is essential for growth of Saccharomyces cerevisiae under various stress conditions. Gene. 1998 Dec 28;225(1-2):39-46. PMID:9931424
3. ↑ Wang G, Yang J, Huibregtse JM. Functional domains of the Rsp5 ubiquitin-protein ligase. Mol Cell Biol. 1999 Jan;19(1):342-52. PMID:9858558
4. ↑ Andoh T, Hirata Y, Kikuchi A. PY motifs of Rod1 are required for binding to Rsp5 and for drug resistance. FEBS Lett. 2002 Aug 14;525(1-3):131-4. PMID:12163175
5. ↑ Kaida D, Toh-e A, Kikuchi Y. Rsp5-Bul1/2 complex is necessary for the HSE-mediated gene expression in budding yeast. Biochem Biophys Res Commun. 2003 Jul 11;306(4):1037-41. PMID:12821147
6. ↑ Abe F, Iida H. Pressure-induced differential regulation of the two tryptophan permeases Tat1 and Tat2 by ubiquitin ligase Rsp5 and its binding proteins, Bul1 and Bul2. Mol Cell Biol. 2003 Nov;23(21):7566-84. PMID:14560004
7. ↑ Crespo JL, Helliwell SB, Wiederkehr C, Demougin P, Fowler B, Primig M, Hall MN. NPR1 kinase and RSP5-BUL1/2 ubiquitin ligase control GLN3-dependent transcription in Saccharomyces cerevisiae. J Biol Chem. 2004 Sep 3;279(36):37512-7. Epub 2004 Jul 9. PMID:15247235 doi:10.1074/jbc.M407372200
8. ↑ Pizzirusso M, Chang A. Ubiquitin-mediated targeting of a mutant plasma membrane ATPase, Pma1-7, to the endosomal/vacuolar system in yeast. Mol Biol Cell. 2004 May;15(5):2401-9. Epub 2004 Mar 12. PMID:15020711 doi:10.1091/mbc.E03-10-0727
9. ↑ Kee Y, Lyon N, Huibregtse JM. The Rsp5 ubiquitin ligase is coupled to and antagonized by the Ubp2 deubiquitinating enzyme. EMBO J. 2005 Jul 6;24(13):2414-24. Epub 2005 Jun 2. PMID:15933713 doi:7600710
10. ↑ Feller A, Boeckstaens M, Marini AM, Dubois E. Transduction of the nitrogen signal activating Gln3-mediated transcription is independent of Npr1 kinase and Rsp5-Bul1/2 ubiquitin ligase in Saccharomyces cerevisiae. J Biol Chem. 2006 Sep 29;281(39):28546-54. Epub 2006 Jul 24. PMID:16864574 doi:10.1074/jbc.M605551200
11. ↑ Ren J, Kee Y, Huibregtse JM, Piper RC. Hse1, a component of the yeast Hrs-STAM ubiquitin-sorting complex, associates with ubiquitin peptidases and a ligase to control sorting efficiency into multivesicular bodies. Mol Biol Cell. 2007 Jan;18(1):324-35. Epub 2006 Nov 1. PMID:17079730 doi:10.1091/mbc.E06-06-0557
12. ↑ Kaminska J, Spiess M, Stawiecka-Mirota M, Monkaityte R, Haguenauer-Tsapis R, Urban-Grimal D, Winsor B, Zoladek T. Yeast Rsp5 ubiquitin ligase affects the actin cytoskeleton in vivo and in vitro. Eur J Cell Biol. 2011 Dec;90(12):1016-28. doi: 10.1016/j.ejcb.2011.08.002. Epub, 2011 Oct 14. PMID:22000681 doi:10.1016/j.ejcb.2011.08.002
13. ↑ Kim HC, Steffen AM, Oldham ML, Chen J, Huibregtse JM. Structure and function of a HECT domain ubiquitin-binding site. EMBO Rep. 2011 Mar 11. PMID:21399621 doi:10.1038/embor.2011.23