Department of Molecular Biology, Umeå University, SE-90187 Umeå, Sweden.
Nucleic Acids Res. 2011 Aug;39(15):6428-39. doi: 10.1093/nar/gkr236. Epub 2011 May 6.
In Drosophila, the global increase in transcription from the male X chromosome to compensate for its monosomy is mediated by the male-specific lethal (MSL) complex consisting of five proteins and two non-coding RNAs, roX1 and roX2. After an initial sequence-dependent recognition by the MSL complex of 150-300 high affinity sites, the spread to the majority of the X-linked genes depends on local MSL-complex concentration and active transcription. We have explored whether any additional RNA species are associated with the MSL complex. No additional roX RNA species were found, but a strong association was found between a spliced and poly-adenylated msl2 RNA and the MSL complex. Based on our results, we propose a model in which a non-chromatin-associated partial or complete MSL-complex titrates newly transcribed msl2 mRNA and thus regulates the amount of available MSL complex by feedback. This represents a novel mechanism in chromatin structure regulation.
在果蝇中，通过由五个蛋白质和两个非编码 RNA（roX1 和 roX2）组成的雄性特异致死（MSL）复合物，从雄性 X 染色体转录的全局增加来补偿其单体性。在 MSL 复合物对 150-300 个高亲和力位点进行初始序列依赖性识别之后，向大多数 X 连锁基因的扩展取决于局部 MSL 复合物浓度和活性转录。我们已经探索了是否有任何其他 RNA 物种与 MSL 复合物相关。没有发现其他的 roX RNA 物种，但在剪接和多聚腺苷酸化的 msl2 RNA 与 MSL 复合物之间发现了强烈的关联。基于我们的结果，我们提出了一个模型，其中非染色质相关的部分或完整 MSL 复合物使新转录的 msl2 mRNA 变构，从而通过反馈调节可用 MSL 复合物的量。这代表了染色质结构调节中的一种新机制。
