Hormonal and cell-specific regulation of Dmrt1

dmrt 1是一个新近发现的基因，编码一个转录因子，其结构特征、表达谱和染色体定位表明它对睾丸发育和功能很重要。 此外，缺乏Dmrt 1的雄性小鼠由于支持细胞分化和生殖细胞存活缺陷而不育。 拟议的研究的目标是确定负责睾丸特异性表达的Dmrt 1的转录机制和Dmrt 1调节睾丸分化的手段。目的一，提出确定的调控元件和结合蛋白的细胞特异性表达和激素调节Dmrt 1。 将通过瞬时转染分析，随后通过蛋白结合研究鉴定相关调控蛋白，对元件进行鉴定和表征。将产生携带由不同长度的Dmrt 1启动子驱动的LacZ报告基因的转基因小鼠，并确定β半乳糖苷酶在时间、空间和激素调节方面的表达谱。 目的研究FSH对Dmrt 1启动子的调控作用，并鉴定其调控元件和蛋白。 这将涉及在存在和不存在添加的激素的情况下通过瞬时转染分析表征启动子突变体，并评估相关的DNA-蛋白质相互作用。 目的二，利用体外结合实验和瞬时转染分析研究Dmrt 1的DNA结合和转录特性。 这将采用基于PCR的测定来鉴定Dmrt 1结合的随机DNA序列，并采用共转染实验来评价Dmrt 1转录活性。最后，将通过使用Dmrt 1的鉴定的高亲和力结合位点搜索候选基因的序列数据库和微阵列分析以比较Dmrt 1表达和非表达细胞系之间的表达谱来鉴定下游靶基因。 dmrt 1作为睾丸功能的重要调节因子的作用表明，识别其上游和下游的作用因子将提供对调节睾丸中基因表达的遗传过程的深入了解，并增强我们对睾丸分化和生育所需的分子事件的理解。

Dmrt1 is a recently described gene encoding a putative transcription factor whose structural features, expression profile, and chromosomal localization suggest it is important for testis development and function. Furthermore, male mice lacking Dmrt1 are infertile due to defects in Sertoli cell differentiation and germ cell survival. The goals of the proposed research are to identify both the transcriptional mechanisms responsible for testis-specific expression of Dmrt1 and the means by which Dmrt1 regulates testis differentiation. Aim I, proposes to identify the regulatory elements and binding proteins necessary for cell-specific expression and hormonal regulation of Dmrt1. Elements will be identified and characterized by transient transfection analysis followed by protein binding studies to identify relevant regulatory proteins. Transgenic mice carrying a LacZ reporter driven by various lengths of the Dmrt1 promoter will be generated and the expression profile for betagalactosidase determined with respect to temporal, spatial, and hormonal regulation. Aim I also proposes to evaluate FSH regulation of the Dmrt1 promoter and identify the responsible regulatory elements and proteins. This will involve characterization of promoter mutants by transient transfection analysis in the presence and absence of added hormone and evaluation of relevant DNA-protein interactions. Aim II, will examine the DNA binding and transcriptional properties of Dmrt1 using in vitro binding assays and transient transfection analysis. This will employ a PCR-based assay to identify randomized DNA sequences to which Dmrt1 binds and co-transfection experiments to evaluated Dmrt1 transcriptional activity. Finally, downstream target genes will be identified by both searching sequence databases for candidate genes using an identified high-affinity binding site for Dmrt1 and microarray analysis to compare the expression profile between Dmrt1 expressing and non-expressing cell lines. Dmrt1's role as an important regulator of testis function suggests that identification of factors acting upstream and downstream of it will provide insight into the genetic processes that regulate gene expression in the testis and enhance our understanding of the molecular events necessary for testis differentiation and fertility.