A small region on the X chromosome of Drosophila regulates a key gene that controls sex determination and dosage compensation.
نویسندگان
چکیده
In Drosophila, flies with two X chromosomes are females, with one X chromosome, males. We investigated the presence of sex determining factors on the X chromosome by constructing genotypes with one X and various X-chromosomal duplications. We found that female determining factors are not evenly distributed along the X chromosome as had been previously postulated. A distal duplication covering 35% of the X chromosome promotes female differentiation, a much larger proximal duplication of 60% results in male differentiation. The strong feminizing effect of distal duplications originates from a small segment that, when present in two doses, activates Sxl, a key gene for sex determination and dosage compensation. Our results suggest that Sxl can be activated to intermediate levels.
منابع مشابه
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عنوان ژورنال:
- Cell
دوره 42 3 شماره
صفحات -
تاریخ انتشار 1985