DWnt-2, a Drosophila Wnt gene required for the development of the male reproductive tract, specifies a sexually dimorphic cell fate.
The sexually dimorphic characteristics of the reproductive tract in Drosophila require that cells of the gonad and the genital disc be assigned sex-specific fates. We report here that DWnt-2, a secreted glycoprotein related to wingless, is a signal required for cell fate determination and morphogenesis in the developing male reproductive tract. Testes from DWnt-2 null mutant flies lack the male-specific pigment cells of the reproductive tract sheath and the muscle precursors of the sheath fail to migrate normally. However, other cell types of the testis are unaffected. DWnt-2 is expressed in somatic cells of the gonad throughout development, implicating it as a signal that can influence pigment cell fate directly. Indeed, the ectopic expression of DWnt-2 in females results in the appearance of male-specific pigment cells in otherwise morphologically normal ovaries. Thus, the presence of pigment cells is a sexually dimorphic trait that is controlled by DWnt-2 expression. DWnt-2 is also expressed in regions of the male genital disc and gonad, which we have identified as sites of contact with muscle precursor cells, suggesting that secreted DWnt-2 protein is a signal for the migration or attachment of these cells.
Kozopas
K M
KM
Howard Hughes Medical Insitute and Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305-5323 USA.
Samos
C H
CH
Nusse
R
R
D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D029721:Drosophila Proteins; D005260:Female; D015870:Gene Expression; D017344:Genes, Insect; D005837:Genitalia, Male / Q000254:growth & development; D008297:Male; D009132:Muscles / Q000196:embryology; D009154:Mutation; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D012733:Sex Differentiation; D013737:Testis / Q000196:embryology; D051154:Wnt2 Protein
D029721:Drosophila Proteins; D011518:Proto-Oncogene Proteins; D051154:Wnt2 Protein; C495251:Wnt2 protein, Drosophila