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

Lina Herhaus; Ana B Perez-Oliva; Giorgio Cozza; Robert Gourlay; Simone Weidlich; David G Campbell; Lorenzo A Pinna; Gopal P Sapkota

doi:10.1126/scisignal.aaa0441

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

Sci Signal. 2015 Apr 14;8(372):ra35. doi: 10.1126/scisignal.aaa0441.

Authors

Lina Herhaus¹, Ana B Perez-Oliva¹, Giorgio Cozza², Robert Gourlay¹, Simone Weidlich¹, David G Campbell¹, Lorenzo A Pinna², Gopal P Sapkota³

Affiliations

¹ MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
² Department of Biomedical Sciences and CNR Institute of Neurosciences, University of Padova, via Ugo Bassi 58/B, 35131 Padova, Italy.
³ MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK. g.sapkota@dundee.ac.uk.

Abstract

The deubiquitylating enzyme OTUB1 is present in all tissues and targets many substrates, in both the cytosol and nucleus. We found that casein kinase 2 (CK2) phosphorylated OTUB1 at Ser(16) to promote its nuclear accumulation in cells. Pharmacological inhibition or genetic ablation of CK2 blocked the phosphorylation of OTUB1 at Ser(16), causing its nuclear exclusion in various cell types. Whereas we detected unphosphorylated OTUB1 mainly in the cytosol, we detected Ser(16)-phosphorylated OTUB1 only in the nucleus. In vitro, Ser(16)-phosphorylated OTUB1 and nonphosphorylated OTUB1 exhibited similar catalytic activity, bound K63-linked ubiquitin chains, and interacted with the E2 enzyme UBE2N. CK2-mediated phosphorylation and subsequent nuclear localization of OTUB1 promoted the formation of 53BP1 (p53-binding protein 1) DNA repair foci in the nucleus of osteosarcoma cells exposed to ionizing radiation. Our findings indicate that the activity of CK2 is necessary for the nuclear translocation and subsequent function of OTUB1 in DNA damage repair.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Active Transport, Cell Nucleus / drug effects
Active Transport, Cell Nucleus / genetics
Animals
Casein Kinase II / antagonists & inhibitors
Casein Kinase II / genetics
Casein Kinase II / metabolism*
Cell Line, Tumor
Cell Nucleus / metabolism*
Cells, Cultured
Cysteine Endopeptidases / genetics
Cysteine Endopeptidases / metabolism*
Deubiquitinating Enzymes
Embryo, Mammalian / cytology
Fibroblasts / cytology
Fibroblasts / drug effects
Fibroblasts / metabolism
HEK293 Cells
HeLa Cells
Humans
Immunoblotting
Lysine / genetics
Lysine / metabolism
Mice, Knockout
Microscopy, Fluorescence
Mutation
Phosphorylation / drug effects
Protein Binding
Protein Kinase Inhibitors / pharmacology
Protein Serine-Threonine Kinases / genetics
Protein Serine-Threonine Kinases / metabolism
RNA Interference
Receptor, Transforming Growth Factor-beta Type I
Receptors, Transforming Growth Factor beta / genetics
Receptors, Transforming Growth Factor beta / metabolism
Serine / genetics
Serine / metabolism*
Transforming Growth Factor beta / pharmacology
Ubiquitin-Conjugating Enzymes / genetics
Ubiquitin-Conjugating Enzymes / metabolism

Substances

Protein Kinase Inhibitors
Receptors, Transforming Growth Factor beta
Transforming Growth Factor beta
Serine
UBE2N protein, human
Ubiquitin-Conjugating Enzymes
Casein Kinase II
Protein Serine-Threonine Kinases
Receptor, Transforming Growth Factor-beta Type I
Deubiquitinating Enzymes
OTUB1 protein, human
Cysteine Endopeptidases
Lysine

Abstract

Publication types

MeSH terms

Substances

Grants and funding