Hedley M L, Maniatis T
Harvard University, Department of Biochemistry and Molecular Biology, Cambridge, Massachusetts 02138.
Cell. 1991 May 17;65(4):579-86. doi: 10.1016/0092-8674(91)90090-l.
Somatic sex determination in Drosophila involves a hierarchy of regulated alternative pre-mRNA processing. Female-specific splicing and/or polyadenylation of doublesex (dsx) pre-mRNA, the final gene in this pathway, requires transformer (tra) and transformer-2 (tra-2) proteins. The mechanisms by which these proteins regulate RNA processing has not been characterized. In this paper we show that tra-2 produced in Escherichia coli binds specifically to a site within the female-specific exon of dsx pre-mRNA. This site, which contains six copies of a 13 nucleotide repeat, is required not only for female-specific splicing, but also for female-specific polyadenylation. These observations suggest that tra-2 is a positive regulator of dsx pre-mRNA processing.
果蝇的体细胞性别决定涉及一系列受调控的可变前体mRNA加工过程。该途径中的最后一个基因——双性基因（doublesex，dsx）前体mRNA的雌性特异性剪接和/或聚腺苷酸化，需要transformer（tra）和transformer-2（tra-2）蛋白。这些蛋白质调节RNA加工的机制尚未明确。在本文中，我们表明在大肠杆菌中产生的tra-2能特异性结合dsx前体mRNA雌性特异性外显子内的一个位点。该位点包含13个核苷酸重复序列的六个拷贝，不仅是雌性特异性剪接所必需的，也是雌性特异性聚腺苷酸化所必需的。这些观察结果表明，tra-2是dsx前体mRNA加工的正调控因子。
