Nagoshi R N, Baker B S
Department of Biological Sciences, Stanford University, California 94305-5020.
Genes Dev. 1990 Jan;4(1):89-97. doi: 10.1101/gad.4.1.89.
Sex-specific alternative RNA splicing of the doublesex (dsx) pre-mRNA results in sex-specific polypeptides that regulate both male and female somatic sexual differentiation in Drosophila melanogaster. We have molecularly characterized a class of dsx mutations that act in cis to disrupt the regulation of dsx RNA processing, causing the dsx pre-mRNA to be spliced in the male-specific pattern regardless of the chromosomal sex of the fly. These dsx mutations are associated with rearrangements in the female-specific exon just 3' to the female-specific splice acceptor. The mutations do not affect the female-specific splice sites or intron that are identical to wild-type sequences. These results indicate that sequences in the female-specific exon are important for the regulation of sex-specific RNA splicing, perhaps by acting as sites of interaction with trans-acting regulators. Furthermore, the data suggest that female-specific regulation of dsx RNA processing occurs by promoting the usage of the female splice acceptor site, rather than by repressing the usage of the alternative male-specific splice acceptor.
双性基因（dsx）前体mRNA的性别特异性可变RNA剪接产生性别特异性多肽，这些多肽调节黑腹果蝇的雄性和雌性体细胞性别分化。我们已经从分子水平上鉴定了一类dsx突变，这些突变顺式作用以破坏dsx RNA加工的调控，导致dsx前体mRNA无论果蝇的染色体性别如何，都以雄性特异性模式进行剪接。这些dsx突变与紧接在雌性特异性剪接受体3'端的雌性特异性外显子的重排有关。这些突变不影响与野生型序列相同的雌性特异性剪接位点或内含子。这些结果表明，雌性特异性外显子中的序列对于性别特异性RNA剪接的调控很重要，可能是作为与反式作用调节因子相互作用的位点。此外，数据表明dsx RNA加工的雌性特异性调控是通过促进雌性剪接受体位点的使用来实现的，而不是通过抑制替代性雄性特异性剪接受体的使用。
