PROTO-ONCOGENES IN GAMETOGENESIS AND EARLY DEVELOPMENT

配子发生和早期发育中的原癌基因

• 批准号: 2378511
• 负责人: GEOFFREY M COOPER
• 金额: $ 23.53万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-01 至 1998-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2378511
• 关键词: 3T3 cells; DNA binding protein; DNA footprinting; HeLa cells; affinity chromatography; developmental genetics; early embryonic stage; embryo /fetus; gametogenesis; gel mobility shift assay; gene expression; genetic promoter element; genetic regulatory element; laboratory mouse; mammalian embryology; northern blottings; nucleic acid probes; oogenesis; protein purification; protein structure function; protooncogene; spermatogenesis; transcription factor; western blottings

The overall goal of the project is understanding the roles of proto- oncogenes in gametogenesis and early development of mammalian embryos. The proposed research is focused on the mechanisms that regulate transcription of the c-mos gene, which plays a critical role in meiosis of vertebrate oocytes. Transcription of c-mos is subject to stringent tissue--specific regulation, leading to its specific expression in male and female germ cells. Such regulation of c-mos is needed not only to achieve appropriate c-mos expression in germ cells but also to prevent inappropriate expression in somatic cells, which can result in either cell death or neoplastic transformation. It is also noteworthy that c- mos expression is downregulated early in embryogenesis, which may be necessary to prevent arrest of embryonic cleavage divisions resulting from the action of Mos as a cytostatic factor. Transcription of c-mos in somatic cells is suppressed by a negative regulatory element (NRE) upstream of the c-mos promoter. In addition, recent studies have identified a candidate somatic cell repressor that binds to a functional element within the c-mos NRE. We now plan to isolate a cDNA clone of the repressor protein and to characterize its mechanism of action in suppressing transcription of c-mos, and possibly other germ cell-specific genes, in somatic cells. Expression of c-mos in oocytes, which is not affected by the NRE, requires only a minimal promoter, including an initiator (Inr) element. These findings suggest the hypothesis that c-mos transcription in oocytes results from a high level of basal transcription activity, which is then suppressed in two-cell embryos. This will be investigated by further studies of the activity of the c-mos Inr in directing transcription in oocytes and embryos, together with analysis of the expression and function of the c-mos repressor during embryonic development. The proposed studies have three specific aims: 1. Isolation and characterization of a cDNA clone for a somatic cell repressor of c-mos transcription. 2. Structure/function analysis and studies of the mechanism of c-mos repressor action. 3. Investigation of the regulation of c-mos transcription in oocytes and early embryos.

该项目的总体目标是了解原始的作用 癌基因生成和哺乳动物胚胎的早期发育。 拟议的研究集中于调节的机制 C-MOS基因的转录在减数分裂中起着至关重要的作用 脊椎动物卵母细胞。 C-MOS的转录受到严格的约束 组织特异性调节，导致其在男性中的特异性表达 和雌性生殖细胞。这种C-MOS的调节不仅需要 在生殖细胞中获得适当的C-MOS表达 在体细胞中的不当表达，这可能导致任何一个 细胞死亡或肿瘤转化。 还值得注意的是 MOS表达在胚胎发生早期被下调，这可能是 防止逮捕胚胎裂解的必要条件 从MOS作为细胞抑制因子的作用。 C-MOS在体细胞中的转录被阴性抑制 C-MOS启动子上游的调节元件（NRE）。 此外， 最近的研究已经确定了一个候选的体细胞阻遏物 与C-MOS NRE中的功能元件结合。 我们现在计划 隔离抑制剂蛋白的cDNA克隆，并表征其 抑制C-MOS转录的作用机理，可能 在体细胞中的其他生殖细胞特异性基因。 C-MOS在不受NRE影响的卵母细胞中的表达 仅需要一个最小的启动子，包括启动器（INR）元素。 这些发现表明卵母细胞中C-MOS转录的假设 由高水平的基础转录活性结果 被抑制在两细胞胚胎中。 这将进一步调查 研究C-MOS INR在指导转录中的活性的研究 卵母细胞和胚胎，以及表达和分析 C-MOS阻遏物在胚胎发育过程中的功能。 拟议的研究具有三个具体目标： 1。分离和表征体细胞的cDNA克隆 C-MOS转录的阻遏物。 2。结构/功能分析和C-MOS机理的研究 阻遏行动。 3。调节卵母细胞中C-MOS转录的调节 和早期胚胎。