Casein kinase 2 (CK2) phosphorylates the deubiquitylase OTUB1 at Ser16 to trigger its nuclear localisation.

ABSTRACT: The deubiquitylating enzyme OTUB1 is ubiquitously expressed and is known to target a multitude of substrates, both in the cytosol and nucleus. Here, we demonstrate that phosphorylation of OTUB1 by Casein kinase 2 (CK2) at Ser16 triggers its nuclear accumulation. CK2 phosphorylates OTUB1 at Ser16 in vitro. In cells, endogenous OTUB1 is phosphorylated at Ser16 and this is blocked by chemical and genetic ablation of CK2 activity. Whereas OTUB1 is detected mainly in the cytosol, OTUB1 phosphorylated at Ser16 is detected only in the nucleus. Inhibition of CK2 causes nuclear exclusion of OTUB1. Although phosphorylation of OTUB1 at Ser16 does not alter its catalytic activity, ability to bind K63-linked ubiquitin chains and ability to interact with the E2 enzyme UBE2N in vitro, the nuclear localisation of OTUB1 appears to be essential for IR-induced DNA-damage repair.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Gopal Sapkota  

LAB HEAD: Gopal P Sapkota

PROVIDER: PXD001711 | Pride | 2015-04-15

REPOSITORIES: Pride