Characterizing the Nematode Dosage Compensation Complex

描述（由申请人提供）：为了弥补有两个X染色体，C。elegans hermaphrodites抑制转录从两个X的一个因素的两倍。Meyer实验室使用了多种细胞学、生物化学和遗传学方法来证明剂量补偿复合物（DCC）在这一过程中很重要。我计划通过纯化来确定这种缩合蛋白样DCC的作用机制，以确定其大小，组成和DNA结合能力。将通过确定DCC与DNA结合的性质来研究复合物的下游效应。目标2将使用遗传筛选来确定剂量补偿复合物沿沿着X染色体扩散所需的成分。这两组实验的目的是了解剂量补偿机制提供的精确转录调控的附加层如何叠加在一般转录机制上。这种理解将有助于建立一个凝聚蛋白样蛋白复合物如何结合DNA，以建立和维持一个稳定遗传的专门染色质状态。

DESCRIPTION (provided by applicant): To compensate for having two X chromosomes, C. elegans hermaphrodites repress transcription from both Xs by a factor of two. The Meyer lab has used a variety of cytological, biochemical, and genetic methods to show that the Dosage Compensation Complex (DCC) is important in this process. I plan to determine the mechanism of action of this Condensin-like DCC by purifying it to determine its size, composition, and DNA binding ability. The downstream effect of the complex will be investigated by determining the nature of DCC binding to DNA. Aim 2 will use a genetic screen to determine what components are required for the dosage compensation complex to spread along the X chromosome. The purpose of both sets of experiments is to understand how the additional layer of precise transcriptional regulation supplied by the dosage compensation machinery can be superimposed on the general transcription machinery. This understanding will help establish how a Condensin-like protein complex binds DNA to establish and maintain a stably inherited specialized chromatin state.