The antiapoptotic protein ICBP90 is a target for protein kinase 2.
Protein kinase 2 (casein kinase 2 [CK2]) is a protein serine/threonine kinase involved in cell proliferation with an expression that is dysregulated in tumors. ICBP90, a transcription factor exhibiting antiapoptotic properties, has several putative CK2 phosphorylation sites. The aim of the present study was to investigate whether ICBP90 could behave as a CK2 substrate. We observed that ICBP90 was more efficiently phosphorylated by the free CK2a subunit than by the heterotetrameric CK2 (alpha(2), beta(2)). Our results suggest that CK2 is an important regulator of the transcriptional activity of ICBP90 and therefore of the antiapoptotic properties of ICBP90. We propose that the "ICBP90 family" members may be substrates for CK2.
Bronner
Christian
C
Institute National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche-S392, Faculté de Pharmacie, B.P. 60024, 67401 Illkirch, France.
Trotzier
Marie-Aline
MA
Filhol
Odile
O
Cochet
Claude
C
Rochette-Egly
Cécile
C
Schöller-Guinard
Marie
M
Klein
Jean-Paul
JP
Mousli
Marc
M
D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism*; D019556:COS Cells; D047390:Casein Kinase II / Q000378:metabolism*; D006801:Humans; D010449:Peptide Mapping; D010766:Phosphorylation; D013379:Substrate Specificity; D044767:Ubiquitin-Protein Ligases
D022762:CCAAT-Enhancer-Binding Proteins; C406364:UHRF1 protein, human; D044767:Ubiquitin-Protein Ligases; D047390:Casein Kinase II