SIGN IN   Advanced Search

Browse Illustration
Wrestling with SUMO in a New Arena

Sumoylation is a widespread posttranslational modification thought to affect primarily nuclear proteins, especially transcription factors for which sumoylation usually results in repression of their transactivational function. Recent proteomics studies have greatly expanded the cadre of known SUMO substrates, and an increasing number of cytoplasmic proteins have been identified as SUMO targets. However, very few of these cytosolic proteins have been evaluated for the functional consequences of sumoylation. Rajan et al. now demonstrate that the activity of an integral cytoplasmic membrane channel-forming protein, K2P1, is completely abrogated by sumoylation at a single lysine residue on the cytoplasmic tail. This is the first report of a plasma membrane protein as a SUMO substrate and explains the long-standing inability to demonstrate functionality of K2P1. Apparently, K2P1 is stoichiometrically sumoylated under most cellular conditions, so it is constitutively inactive until desumoylated. These observations raise several intriguing questions, including: How and where does K2P1 become sumoylated? Why, unlike most known substrates, is K2P1 so efficiently sumoylated? and, What are the signals and SUMO proteases that trigger K2P1 desumoylation? But most importantly, the report by Rajan et al. expands the functional roles attributed to sumoylation into the new arena of membrane protein functional regulation and suggests that similar mechanisms may regulate the function of other pore proteins.

Rate this Resource:
1 = not useful, 5 = very useful

Please be the first to rate this resource.

Subscribe and
View Resource


Resource Type: Diagram, Illustration, Journal article/Issue, Review
Audience Level: Undergraduate upper division 15-16, Graduate, Professional (degree program)

Author and Copyright

Authors and Editors: Van G. Wilson of Department of Medical Microbiology and Immunology and the College of Medicine, Texas A&M University System Health Science Center, German Rosas-Acosta of Department of Medical Microbiology and Immunology and the College of Medicine, Texas A&M University System Health Science Center
Publisher: American Association for the Advancement of Science
Format: application/pdf, image/gif, image/jpeg, text/html
Copyright and other restrictions: Yes
Cost: Yes


» Sign In or register to post comments.

STKE/Science Signaling



Triple A S National Science Foundation Naitonal Science Digital Library Pathway
Funded by the individual BEN Collaborators and grants from the
National Science Foundation [DUE 0085840 / DUE 0226185 / DUE 0532797 / DUE 0734995]

This website is a National Science Digital Library (NSDL) Pathway.
Copyright © 2019. American Association for the Advancement of Science. All Rights Reserved.