DUBs: Regulation by Reversible Ubiquitination

Perspective

J Mol Biol & Mol Imaging. 2015;2(1): 1014.

DUBs: Regulation by Reversible Ubiquitination

Manisha Sharma and Girdhar K. Pandey*

Department of Plant Molecular Biology, University of Delhi South Campus, India

*Corresponding author: Girdhar K Pandey, Department of Plant Molecular Biology, University of Delhi South Campus, India

Received: February 14, 2015; Accepted: March 05, 2015; Published: March 06, 2015

Abstract

Deubiquitinases (DUBs) are the class of enzymes that serve to reverse the ubiquitination by cleaving and releasing ubiquitin moity from the modified proteins. Corresponding to E3 ligases, eukaryotic genomes also encode several DUB proteins that are further divided into subfamilies. The activity and functions of DUB proteins are enigmatic in the sense that upon binding ubiquitin or a protein scaffold they frequently undergo a confirmational change. The association of DUBs with different substrate protein complexes regulate their specificity towards target proteins. Recent studies in human and yeast have led to new insights into the role of DUBs in various cellular processes.

Keywords: Ubiquitin; DUBs; Enzymes; Protein

DUB Protein Complement in Plants

Plants have evolved a sophisticated armoury of proteins for the regulation of critical cellular signalling events. Post-translational modifications of proteins typically by reversible ubiquitination is associated with proteolysis of target protein by the 26S proteasome [1-2]. Moreover, the covalent attachment of ubiquitin to proteins not only target them for degradation but also influence their localization, activation and hence their stability. Ubiquitylation is sequentially regulated by a set of activating (E1), conjugating (E2) and ligase (E3) enzymes to facilitate the covalent attachment of ubiquitin on the substrate protein [1-3]. The substrate protein can be modified by the addition of single or multiple ubiquitin residues. The fate of ubiquitin bound substrate largely depends on the length and topology of ubiquitin oligomer. The subsequent addition of more than four ubiquitin residues facilitates efficient binding and degradation of modified protein by the 26S proteasome [3] (Figure 1).

Citation: Sharma M and Pandey GK. DUBs: Regulation by Reversible Ubiquitination. J Mol Biol & Mol Imaging. 2015;2(1): 1014. ISSN:2471-0237