title: Clonal analysis ofsex-lethal, a gene needed for female sexual development inDrosophila melanogaster.
abstract: The mutationSxlf, located on the X-chromosome, is a sex-limited recessive lethal that specifically kills 2X; 2A flies while it does not affect X; 2A flies (Cline 1978). We have analyzed the role ofSxlfon sex determination by a clonal analysis of a new spontaneous allele,SxlfLS. Female embryos and larvae heterozygous forSxlfLSwere irradiated at different times of development to generate homozygousSxlfLSclones which were recognized by linked marker mutations. We have studied the phenotype of such clones on sexually dimorphic regions of the fly (foreleg basitarsus, 5th, 6th and 7th tergites, analia and external genitalia). Despite their female (2X; 2A) chromosomal constitution, clones homozygous forSxlfLSdifferentiated male structures. These results confirm and extend the preliminary report of Cline (1979). They show that the wildtype product ofSxlfis required for female development.
authors.affiliation: Zoologisches Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
authors.forename: Lucas
authors.initials: L
authors.lastname: Sánchez
authors.affiliation: Zoologisches Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
authors.forename: Rolf
authors.initials: R
authors.lastname: Nöthiger
keywords: Clonal analysis; Drosophila; Sex determination