The N-terminal domain of Sxl protein disrupts Sxl autoregulation in females and promotes female-specific splicing of tra in males.

摘要: Sex determination in Drosophila depends upon the post-transcriptional regulatory activities of Sex-lethal (Sxl) gene. Sxl maintains female determined state and activates differentiation pathways by directing female-specific splicing tra pre-mRNAs. While there is compelling evidence that proteins regulate directly binding to target RNAs, previous studies indicate two RNA-binding domains are not themselves sufficient for biological activity an intact N-terminal domain also critical function. To further investigate functions N terminus, we ectopically expressed a chimeric protein consisting 99 amino acids fused ss-galactosidase. The Nss-gal fusion behaves like dominant negative, interfering with autoregulatory feedback loop killing females. This negative can be attributed recruitment into large Sxl:Snf complexes found vivo consequent disruption these complexes. In addition activity, has novel gain-of-function males: it promotes processing discussed light blockage model regulation.