The role of the Drosophila LAMMER protein kinase DOA in somatic sex determination.
DOA kinase, the Drosophila member of the LAMMER/Clk protein kinase family, phosphorylates SR and SR-like proteins, including TRA, TRA2 and RBP1, which are responsible for the alternative splicing of transcripts encoding the key regulator of sex-specific expression in somatic cells of the fly, DOUBLESEX. Specific Doa alleles induce somatic female-to-male sex transformations, which can be enhanced when combined with mutations in loci encoding SR and SR-like proteins. The Doa locus encodes six different kinases, of which a 69-kDa isoform is expressed solely in females. Expression of this isoform is itself under the regulation of the somatic sex determination regulatory network, thus forming a putative positive autoregulatory loop which would reinforce the choice of the female cell-fate. We speculate that this loop is part of the evolutionary ancestral sex-determination machinery, based upon evidence demonstrating the existence of an autoregulatory loop involving TRA and TRA2 in several other insect species.
Rabinow
Leonard
L
Université Paris Sud 11, Centre de Neurosciences de Paris Sud, Bâtiment 442 bis, 91405 Orsay Cedex, France. Leonard.Rabinow@u-psud.fr
Samson
Marie-Laure
ML
D017398:Alternative Splicing / Q000235:genetics; D000818:Animals; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000201:enzymology* / Q000235:genetics; D005260:Female; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D019849:Sex Determination Processes
D029721:Drosophila Proteins; D007527:Isoenzymes; C089977:Doa protein, Drosophila; D017346:Protein Serine-Threonine Kinases