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Cloning of cDNAs encoding Bombyx homologues of Cdc2 and Cdc2-related kinase from eggs

Iwasaki, H., Takahashi, M., Niimi, T., Yamashita, O., Yaginuma, T.
Insect molecular biology 1997 v.6 no.2 pp. 131-141
messenger RNA, structural genes, complementary DNA, ova, cell division, amino acid sequences, gene expression, diapause, Bombyx mori, nucleotide sequences, embryogenesis
In diapasons eggs of the silkworm, Bombyx mori, embryonic cell are arrested at G2 phase. The ability to undertake cell division is resumed in the course of diapause termination caused by such a treatment as acclimation to 5 degrees C. As an initial trial to investigate the relationship between diapause and embryonic cell cycling, we have cloned and sequenced two Bombyx cDNAs encoding two distinct cdc2-related Ser/Thr protein kinase. One (Bm cdc2) encoded a 37.0 kDa protein which had all of the domain characteristic of other Cdc2 kineses. The other (Bcdrk) encoded a 45.1 kDa protein that was most similar to Drosophila and human cdc2-related protein kinase (Dcdrk protein and PISSRLE kinase). Northern blot analysis was carried out to examine levels of Bm cdc2 and Bcdrk. mRNA during embryogenesis of non-diapause eggs. The result demonstrated that the mRNA level of Bm cdc2 appeared to correspond to the activity of nuclear/cellular division in non diapause eggs, and that the developmental profile in the level of Bcdrk mRNA was somewhat different from that of Bm cdc2 mRNA.