Structural highlights
Function
PSA3_HUMAN The proteasome is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. The proteasome has an ATP-dependent proteolytic activity. Binds to the C-terminus of CDKN1A and thereby mediates its degradation. Negatively regulates the membrane trafficking of the cell-surface thromboxane A2 receptor (TBXA2R) isoform 2.[1] [2]
Publication Abstract from PubMed
The proteasome is a highly regulated protease complex fundamental for cell homeostasis and controlled cell cycle progression. It functions by removing a wide range of specifically tagged proteins, including key cellular regulators. Here we present the structure of the human 20S proteasome core bound to a substrate analogue inhibitor molecule, determined by electron cryo-microscopy (cryo-EM) and single-particle analysis at a resolution of around 3.5 A. Our map allows the building of protein coordinates as well as defining the location and conformation of the inhibitor at the different active sites. These results open new prospects to tackle the proteasome functional mechanisms. Moreover, they also further demonstrate that cryo-EM is emerging as a realistic approach for general structural studies of protein-ligand interactions.
Cryo-EM reveals the conformation of a substrate analogue in the human 20S proteasome core.,da Fonseca PC, Morris EP Nat Commun. 2015 Jul 2;6:7573. doi: 10.1038/ncomms8573. PMID:26133119[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Touitou R, Richardson J, Bose S, Nakanishi M, Rivett J, Allday MJ. A degradation signal located in the C-terminus of p21WAF1/CIP1 is a binding site for the C8 alpha-subunit of the 20S proteasome. EMBO J. 2001 May 15;20(10):2367-75. PMID:11350925 doi:http://dx.doi.org/10.1093/emboj/20.10.2367
- ↑ Sasaki M, Sukegawa J, Miyosawa K, Yanagisawa T, Ohkubo S, Nakahata N. Low expression of cell-surface thromboxane A2 receptor beta-isoform through the negative regulation of its membrane traffic by proteasomes. Prostaglandins Other Lipid Mediat. 2007 Jun;83(4):237-49. Epub 2006 Dec 27. PMID:17499743 doi:http://dx.doi.org/10.1016/j.prostaglandins.2006.12.001
- ↑ da Fonseca PC, Morris EP. Cryo-EM reveals the conformation of a substrate analogue in the human 20S proteasome core. Nat Commun. 2015 Jul 2;6:7573. doi: 10.1038/ncomms8573. PMID:26133119 doi:http://dx.doi.org/10.1038/ncomms8573