XIST RNA AND ASSOCIATED TRANS ACTING FACTORS

小鼠Xist基因编码剂量所需的非翻译RNA 补偿。Xist RNA是从不活跃的X染色体上表达的 雌性小鼠细胞，是转录沉默所必需的 几乎所有其他基因都位于不活跃的X染色体上。 专门覆盖不活跃的X染色体。走向序列的区域 Xist作用因子的小鼠和人类同源物之间存在保守性 这可能会束缚Xist并参与剂量补偿过程 都还没有确定。 获取保守区功能重要性的策略 Xist将被实施，结合Xist RNA的反式作用因子将 被指认出来。含有精确缺失基因的转基因Xist基因 保守区将在模型细胞培养系统中表达，并且 这些突变的影响将通过执行 建立了Xist功能和RNA定位的检测方法。此外, 有独立的方法来识别反式作用因素 结合Xist RNA保守区的基因被概述。遵循他们的 这些反式作用因子的生物学意义 将由正在开发的抗体处理以评估细胞内 Xist结合蛋白的定位。此外，Xist RNA-蛋白质相互作用 将在体外进行研究。

The mouse Xist gene encodes an un-translated RNA required for dosage compensation. Xist RNA is expressed from the inactive X chromosome in female mouse cells and is required for the transcriptional silencing of virtually all other genes resident on the inactive X chromosome.Xist RNA specifically coats the inactive X chromosome. Regions of striking sequence conservation occur between mouse and human homologs of Xist acting factors that likely bind Xist and participate in the dosage compensation process have yet to be identified. A strategy to access the functional significance of conserved regions of Xist will be implemented and trans-acting factors that bind Xist RNA will be identified. Transgenic Xist genes containing precise deletion of the conserved regions will be expressed in a model cell-culture system, and the effects of these mutations will be determined by performing established assays for Xist function and RNA localization. In addition, there independent approaches designed to identify trans-acting factors that bind to conserved regions of Xist RNA are outlined. Following their identification, the biological significance of these trans-acting factors will be addressed by the developing antibodies to assess the intracellular locations of Xist binding proteins. Also, Xist RNA-protein interactions will be studied in vitro.