Defining an Embedded Code for Protein Ubiquitination
Trafina Jadhav and Marie W. Wooten*
Program in Cellular and Molecular Biosciences, Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA
- *Corresponding Author:
- Dr. Marie W. Wooten
Program in Cellular and Molecular Biosciences
Department of Biological Sciences
Auburn University, Auburn
AL, 36849, USA
Tel: (334) 844-9226
Fax: +1 (334) 844-5255
E-mail : [email protected]
Received Date: June 26, 2009; Accepted Date: July 23, 2009; Published Date: July 24, 2009
Citation: Jadhav T, Wooten M (2009) Defining an Embedded Code for Protein Ubiquitination. J Proteomics Bioinform 2: 316-333. doi: 10.4172/jpb.1000091
Copyright: © 2009 Jadhav T. et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
It has been more than 30 years since the initial report of the discovery of ubiquitin as an 8.5 kDa protein of unknown function expressed universally in living cells. And still, protein modification by covalent conjugation of the ubiquitin molecule is one of the most dynamic posttranslational modifications studied in terms of biochemistry and cell physiology. Ubiquitination plays a central regulatory role in number of eukaryotic cellular processes such as receptor endocytosis, growth-factor signaling, cell-cycle control, transcription, DNA repair, gene silencing, and stress response. Ubiquitin conjugation is a three step concerted action of the E1-E2-E3 enzymes that produces a modified protein. In this review we investigate studies undertaken to identify both ubiquitin and SUMO (small ubiquitin-related modifier) substrates with the goal of understanding how lysine selectivity is achieved. The SUMOylation pathway though distinct from that of ubiquitination, draws many parallels. Based upon the recent findings, we present a model to explain how an individual ubiquitin ligase may target specific lysine residue(s) with the co-operation from a scaffold protein.