Ubiquitin-specific protease-like 1 (USPL1) is a SUMO isopeptidase with essential, non-catalytic functions.

ABSTRACT: Isopeptidases are essential regulators of protein ubiquitination and sumoylation. However, only two families of SUMO isopeptidases are at present known. Here, we report an activity-based search with the suicide inhibitor haemagglutinin (HA)-SUMO-vinylmethylester that led to the identification of a surprising new SUMO protease, ubiquitin-specific protease-like 1 (USPL1). Indeed, USPL1 neither binds nor cleaves ubiquitin, but is a potent SUMO isopeptidase both in vitro and in cells. C13orf22l--an essential but distant zebrafish homologue of USPL1--also acts on SUMO, indicating functional conservation. We have identified invariant USPL1 residues required for SUMO binding and cleavage. USPL1 is a low-abundance protein that colocalizes with coilin in Cajal bodies. Its depletion does not affect

SUBMITTER: Schulz S 

PROVIDER: S-EPMC3463963 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature