REGULATION OF THE NEURAL DETERMINATION GENE MASH1

描述：本应用程序主要关注的是 小鼠神经基因MASH-1。Mash-1编码一种DNA结合蛋白 属于bHLH家族；其表达和功能丧失表型 得到了广泛的研究。在上一个批准期内， 申请人已着手确定顺应性因素和交易因素 控制小鼠神经系统中MASH-1的表达。这些 经过努力，鉴定出了一个1.2kB的序列，该序列能够 驱动LacZ报告基因的模式类似于 内源性MASH-1表达。相关顺位代理的地点 元素已通过删除构造进一步缩小范围；三个 在1.2kB片段中发现了150bpp的区域，其缺失导致 导致部分LacZ表达的显著损失。它也是 发现报告结构的表达在 MASH-1纯合突变背景，提示MASH-1蛋白可能 作为其自身表达的抑制因素。最后，申请者拥有 提供了令人信服的初步证据，与先前相反 有报道称，MASH-1基因敲除小鼠的中枢神经系统出现明显缺陷。目标 本提案的1-3项意在确定特定的结合部位 1.2kB MASH-1突变脑组织中的转录因子。

DESCRIPTION: This application focusses on regulation and function of the mouse proneural gene MASH-1. MASH-1 encodes a DNA binding protein of the bHLH family; its expression and loss of function phenotype has been studied extensively. During the previous granting period the applicant has set out to identify cis- and transacting factors controlling MASH-1 expression in the mouse nervous system. These efforts resulted in the identification of a 1.2kB sequence which is able to drive a lacZ reporter gene in a pattern similar to that one of endogenous MASH-1 expression. The location of relevant cis-acting elements has been further narrowed down by deletion constructs; three 150bpp regions were identified within the 1.2kB piece whose deletion led to significant losses of part of the lacZ expression. It was also discovered that expression of the reporter constructs is upregulated in homozygous MASH-1 mutant background, suggesting that MASH-1 protein may act as an inhibitor of its own expression. Finally, the applicant has furnished convincing preliminary evidence that, contrary to prior reports, MASH-1 knockout mice show significant defects in the CNS. Aims 1-3 of this proposal intend to identify specific binding sites for transcription factors in the 1.2kB MASH-1 mutant brains.