title: CK2 is acting upstream of MEK3/6 as a part of the signal control of ERK1/2 and p38 MAPK during keratinocytes autocrine differentiation.
abstract: Protein kinase CK2 (formerly termed "casein kinase II") is a ubiquitously in mammalian cells distributed Ser/Thr kinase, with global role in cell regulation. Although, the involvement of CK2 in cell signalling is vast-investigated, virtually nothing is known about its contribution to signal control of keratinocytes differentiation. Here we show that, in autocrine differentiating keratinocytes, inhibition of the CK2 activity induced by 4,5,6,7-tetrabromobenzotriazole (TBB) causes reciprocal changes in the activities of major signal transduction regulators of keratinocytes differentiation, i.e. ERK1/2 and p38 MAPK, without affecting their protein levels. The ERK1/2 activity is strongly suppressed, while the activity of p38 is increased. We have also found that the activity of upstream and specific for p38 MAPK kinase MEK3/6 is also stimulated by TBB. These original results clearly demonstrate the participation of CK2 in the signal transduction pathway controlling MEK3/6, p38 MAPK, and ERK1/2 in the used model system.
authors.affiliation: Department of Medical Chemistry and Biochemistry, Medical University of Sofia, 2 Zdrave Str., 1431 Sofia, Bulgaria. antonia_isaeva@yahoo.com
authors.forename: Antonia R
authors.initials: AR
authors.lastname: Isaeva
authors.forename: Vanio I
authors.initials: VI
authors.lastname: Mitev
mesh_terms: D015153:Blotting, Western; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000201:enzymology; D011494:Protein Kinases / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D011494:Protein Kinases