Sex-specific regulation of the male-specific lethal-1 dosage compensation gene in Drosophila.
Dosage compensation in Drosophila occurs by a twofold increase in transcription per copy of X-linked genes in males (XY) compared with females (XX). msl-1 is one of four genes that are essential for dosage compensation in males, and MSL-1 protein is associated specifically with the male X chromosome. To explore the basis for the sex specificity of dosage compensation, we examined MSL-1 expression in males, females, and dosage compensation mutants. MSL-1 protein levels are negatively regulated by Sxl in females, resulting in male-specific expression of MSL-1. In addition, msl-2 is required for translation and/or stability of MSL-1 in males. Furthermore, the wild-type pattern of MSL-1 localization to the X chromosome is dependent on mle and msl-3 function, although a subset of sites are stained with MSL-1 antibodies in these mutants. Collectively, these data provide the first evidence for an order of msl gene function and suggest that male-specific expression of MSL-1 plays a key role in the sex specificity of dosage compensation.
Palmer
M J
MJ
Department of Entomology, Oklahoma State University, Stillwater 74078.
Richman
R
R
Richter
L
L
Kuroda
M I
MI
D000818:Animals; D015153:Blotting, Western; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development; D005260:Female; D018628:Gene Dosage; D005804:Genes, Lethal; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D007814:Larva; D008297:Male; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics*; D012727:Sex Characteristics; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*
D029721:Drosophila Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; C082132:msl-1 protein, Drosophila