Format

Send to:

Choose Destination
See comment in PubMed Commons below
Biochem J. 2009 Jun 26;421(2):223-30. doi: 10.1042/BJ20090246.

Characterization of SENP7, a SUMO-2/3-specific isopeptidase.

Author information

  • 1Wellcome Trust Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD15EH, Scotland, UK.

Abstract

The modification of proteins by SUMO (small ubiquitin-related modifier) plays important roles in regulating the activity, stability and cellular localization of target proteins. Similar to ubiquitination, SUMO modification is a dynamic process that can be reversed by SENPs [SUMO-1/sentrin/SMT3 (suppressor of mif two 3 homologue 1)-specific peptidases]. To date, six SENPs have been discovered in humans, although knowledge of their regulation, specificity and biological functions is limited. In the present study, we report that SENP7 has a restricted substrate specificity, being unable to process SUMO precursors and displaying paralogue-specific isopeptidase activity. The C-terminal catalytic domain of SENP7 efficiently depolymerized poly-SUMO-2 chains but had undetectable activity against poly-SUMO-1 chains. SENP7 also displayed isopeptidase activity against di-SUMO-2- and SUMO-2-modified RanGAP1 (Ran GTPase-activating protein 1) but had limited activity against SUMO-1-modified RanGAP1. in vivo, full-length SENP7 was localized to the nucleoplasm and preferentially reduced the accumulation of high-molecular-mass conjugates of SUMO-2 and SUMO-3 compared with SUMO-1. Small interfering RNA-mediated ablation of SENP7 expression led to the accumulation of high-molecular-mass SUMO-2 species and to the accumulation of promyelocytic leukaemia protein in subnuclear bodies. These findings suggest that SENP7 acts as a SUMO-2/3-specific protease that is likely to regulate the metabolism of poly-SUMO-2/3 rather than SUMO-1 conjugation in vivo.

PMID:
19392659
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Portland Press
    Loading ...
    Write to the Help Desk