Kalmykova, Alla I3; Shevelyov, Yuri Y3; Polesskaya, Oksana O3; Dobritsa, Anna A3; Evstafieva, Alexandra G3; Boldyreff, Brigitte3; Issinger, Olaf-Georg4; Gvozdev, Vladimir A3
1 Faculty of Science, SDU2 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU3 unknown4 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU
An earlier described CK2(beta)tes gene of Drosophila melanogaster is shown to encode a male germline specific isoform of regulatory beta subunit of casein kinase 2. Western-analysis using anti-CK2(beta)tes Ig revealed CK2(beta)tes protein in Drosophila testes extract. Expression of a CK2(beta)tes-beta-galactosidase fusion protein driven by the CK2(beta)tes promoter was found in transgenic flies at postmitotic stages of spermatogenesis. Examination of biochemical characteristics of a recombinant CK2(beta)tes protein expressed in Escherichia coli revealed properties similar to those of CK2beta: (a) CK2(beta)tes protein stimulates CK2alpha catalytic activity toward synthetic peptide; (b) it inhibits phosphorylation of calmodulin and mediates stimulation of CK2alpha by polylysine; (c) it is able to form (CK2(beta)tes)2 dimers, as well as (CK2alpha)2(CK2(beta)tes)2 tetramers. Using the yeast two-hybrid system and coimmunoprecipitation analysis of protein extract from Drosophila testes, we demonstrated an association between CK2(beta)tes and CK2alpha. Northern-analysis has shown that another regulatory (beta') subunit found recently in D. melanogaster genome is also testis-specific. Thus, we describe the first example of two tissue-specific regulatory subunits of CK2 which might serve to provide CK2 substrate recognition during spermatogenesis.
European Journal of Biochemistry, 2002, Vol 269, Issue 5, p. 1418-27
Animals; Calmodulin; Casein Kinase II; Catalysis; Drosophila Proteins; Drosophila melanogaster; Isoenzymes; Male; Organ Specificity; Polylysine; Protein Subunits; Protein-Serine-Threonine Kinases; Repressor Proteins; Testis; Two-Hybrid System Techniques