Sex-specific transcripts of the Dstpk61 serine threonine kinase gene in Drosophila melanogaster

We describe the characterization of several transcripts of the Drosophila s erine/threonine protein kinase 61 (Dstpk61) gene. Dstpk61 produces at least four transcripts, including a 3.0-kb testis-specific transcript, a 4.5-kb female-specific carcass transcript, a 3.5-kb ovary-specific transcript, and a 4.7-kb non-sex-specific transcript. Two cDNAs, a 3.5-kb cDNA (cDNA(B)) a nd a 3.0-kb cDNA (cDNA(A)), likely to correspond to either the non-specific or the female-specific carcass and the testis-specific transcript, respect ively, were fully sequenced and found to encode a novel OPA-repeat-containi ng serine/threonine-specific protein kinase. cDNA(A) and cDNA(B) both conta in the entire ORF that encodes this predicted protein, but differ in the un translated regions. The cDNAs contain translational control elements which are found in transcripts under male germline-specific translational control , and doublesex-like 13-nucleotide repeat elements, which are required for transformer/transformer-2-mediated splicing of the female doublesex transcr ipt. The complex tissue and sex-specific transcripts, differing in the untr anslated regions which are likely to be crucial in translational control, s uggest that this kinase may have both general and sex-specific functions. T he protein is homologous to human 3-phosphoinositide dependent protein kina se, which is involved in transduction of insulin signalling.