tailieunhanh - Báo cáo y học: "Deciphering histone 2A deubiquitination"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Deciphering histone 2A deubiquitination. | Minireview Deciphering histone 2A deubiquitination Michael J Clague Judy M Coulson and Sylvie Urbé Address Physiological Laboratory School of Biomedical Sciences University of Liverpool Crown St Liverpool L69 3BX UK. Correspondence Michael J Clague. Email clague@. Sylvie Urbé. Email urbe@ Published 23 January 2008 Genome Biology 2008 9 202 doi gb-2008-9-1-202 The electronic version of this article is the complete one and can be found online at http 2008 9 1 202 2008 BioMed Central Ltd Abstract Three recent papers have identified distinct enzymes that can remove ubiquitin from mammalian histone 2A H2A . Functions in transcriptional activation DNA repair and control of the cell cycle have been proposed for these enzymes. Ubiquitination is a reversible posttranslational modification of proteins that could rival phosphorylation in its scope and complexity. Removal of ubiquitin is accomplished through the action of deubiquitinating enzymes DUBs which fall into five distinct families in the human genome containing about 84 active members 1 2 . Post-translational modifications of histones include methylation acetylation sumoylation and ubiquitination enabling a combinatorial code to regulate chromatin structure 3 and recruit protein complexes 4 . An example of the interplay between these modifications is provided by the activity of Ubp8 a yeast deubiquitinating enzyme which regulates the methylation of histone 3 H3 on lysine 4 K4 methylation by deubiquitinating histone 2B H2B 5 . About 5-15 of histone 2A H2A is monoubiquitinated in mammalian cells making it the most abundant ubiquitinated protein in the nucleus in fact it was the first example of a ubiquitinated protein to be described 6 . Mono-ubiquitination is not linked to protein degradation but instead plays a role in transcriptional control DNA repair and other processes. It has also long been known that deubiquitination of histones occurs during metaphase of the cell .