THE BETA-CK2TES-GENE ENCODES THE TISSUE-SPECIFIC REGULATORY SUBUNIT OF CASEIN-KINASE-2 IN DROSOPHILA-MELANOGASTER

The beta CK2tes gene encodes a new variant of the tissue-specific regu latory beta-subunit of casein kinase 2 (CK2). The beta CK2tes open rea ding frame comprises nucleotide stretches encoding for the conservativ e polypeptide motifs characteristic for the CK2 beta-subunit including the Glu/Asp rich region responsible for regulation of CK2, C-terminal fragment responsible for binding to the catalytic alpha-subunit, and ''zinc finger'' motif. Unlike conserved sequences of CK2 beta-subunits in other organisms, the beta CK2tes polypeptide has no autophosphoryl ation site or other putative phosphorylation sites. beta CK2tes is exp ressed only in testes, whereas beta CK2 expression is maximal at embry onic stages and is detected also in larvae. We suggest that beta CK2te s determines substrate specificity of CK2 and/or CK2 activity during s permatogenesis in Drosophila.