RRC ID 545
Author Suzuki MG, Funaguma S, Kanda T, Tamura T, Shimada T.
Title Role of the male BmDSX protein in the sexual differentiation of Bombyx mori.
Journal Evol Dev
Abstract The sex determination pathway is different between Drosophila melanogaster and Bombyx mori in the initial signal. Here we show evidence that the sex determination pathway in B. mori is similar to that of D. melanogaster at the level of the terminal regulator, doublesex (dsx), which is essential for the proper differentiation of the sexually dimorphic somatic features of D. melanogaster. In B. mori, a homolog of dsx (Bmdsx) is expressed in various tissues, and its primary transcript is alternatively spliced in males and females to yield sex-specific mRNAs that encode male-specific (BmDSXM) and female-specific (BmDSXF) polypeptides. In the studies reported here, transgenic silkworms carrying a construct with a Bmdsx male cDNA placed under the control of either an hsp70 promoter or a Bombyx actin3 promoter were generated by piggyBac-mediated germline transformation. Ectopic expression of the male cDNA in females resulted in abnormal differentiation of certain female-specific genital organs and caused partial male differentiation in female genitalia. Transgenic analysis also revealed that the expression of BmDSXM in females caused repression of the female-specifically expressed gene, the vitellogenin gene, and also resulted in activation of the pheromone-binding protein gene that is dominantly expressed in males. These results provide evidence that the role of BmDSXM includes the activation of some aspects of male differentiation as well as the repression of female differentiation. Taken together with our previous data on the function of BmDSXF, we can conclude that Bmdsx is a double-switch gene at the final step in the sex-determination cascade of B. mori.
Volume 7(1)
Pages 58-68
Published 2005-1-1
DOI 10.1111/j.1525-142X.2005.05007.x
PII EDE05007
PMID 15642090
MeSH Animals Animals, Genetically Modified Blotting, Northern Bombyx DNA / metabolism DNA, Complementary / metabolism DNA-Binding Proteins / metabolism DNA-Binding Proteins / physiology* Female Gene Expression Regulation, Developmental* Genitalia, Female / pathology Genitalia, Male / pathology HSP70 Heat-Shock Proteins / genetics Insect Proteins / metabolism Insect Proteins / physiology* Male Models, Anatomic Polymerase Chain Reaction Promoter Regions, Genetic RNA, Messenger / metabolism Reverse Transcriptase Polymerase Chain Reaction Sex Differentiation* Sex Factors Time Factors Transgenes Vitellogenins / genetics
IF 1.925
Times Cited 72
Silkworms EST database