PARACRINE REGULATION: SERTOLI/GERM CELL INTERACTIONS

旁分泌调节：支持细胞/生殖细胞相互作用

• 批准号: 6387601
• 负责人: PATRICIA L. MORRIS
• 金额: $ 29.14万
• 依托单位: POPULATION COUNCIL
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6387601
• 关键词: DNA binding protein; JAK kinase; Sertoli cells; cell cell interaction; cell growth regulation; cytokine receptors; dynorphins; enkephalins; enzyme activity; gene expression; genetic regulation; germ cells; interferon alpha; interferon gamma; interleukin 12; interleukin 4; interleukin 6; laboratory mouse; opioid receptor; paracrine; phosphorylation; protein protein interaction; protein structure function; tissue /cell culture; transcription factor

Protein-protein interactions involving specific DNA binding domains appear to play a critical role in gene transcription and its regulation. Our working hypothesis is that such regulatory mechanisms exist in both Sertoli cells and meiotic germ cells and mediate transcriptional activation of elements (e.g. STAT-GAS DNA binding complexes) in the promoters of cytokine-responsive genes, thereby influencing critical transitions in phenotypic expression. Our workplan will use both loss- and gain- of function experimental models to address the roles of STAT-4, STAT-6 and the tyrosine kinase JAK3 in meiotic and early haploid gene expression. Using meiotic prophase as a focal point, we will examine whether critical transition points are influenced by the activation and/or inhibition of spermatocyte STAT-DNA binding. In the pre- meiotic, meiotic prophase and early haploid germ cells, we propose to test whether the transcription factors STAT-4 and STAT-6 will define (a) the platform characteristics of the DNA binding complexes formed following a cytokine signal, (b) the potential for transcriptional control of those opioid (e.g. germ cell specific enkephalin promoter) and meiotic genes (e.g. synaptonemal complex) whose promoters contain functional and distinctive STAT-binding elements and, (c) molecular mechanism(s) mediating the paracrine interactions between germ cells and Sertoli cells (e.g. somatic cell enkephalin promoter and opioid receptors) in a stage-specific manner. Studies proposed in Specific Aims 1 and 3 will test the hypothesis that interleukin-12, interleukin-4, and interferon- alpha/gamma represent both positive and negative autocrine/paracrine cues that influence meiotic gene expression and progression to the early haploid phenotype. Those studies planned in Specific Aim 2 will characterize the Sertoli cell- specific mechanisms that mediate the paracrine interactions subserved by interleukin and opioid growth factors. We anticipate that the results of our studies will identify and further characterize novel transcription factors involved in the regulation of meiosis in the male germ line. The testis represents a unique system in which to delineate the consequences of JAK3 tyrosine phosphorylation, cell-to-cell signalling via interleukin-4 and interleukin-12 during development, and the distinct roles of STAT-4 and STAT-6 in gene transcription, providing mechanistic insight that ma also be relevant to lymphocyte development and immune disorders.

涉及特定 DNA 结合域的蛋白质-蛋白质相互作用似乎在基因转录及其调控中发挥着关键作用。 我们的工作假设是，这种调节机制存在于支持细胞和减数分裂生殖细胞中，并介导细胞因子反应基因启动子中元件（例如STAT-GAS DNA结合复合物）的转录激活，从而影响表型表达的关键转变。 我们的工作计划将使用功能丧失和获得功能实验模型来解决 STAT-4、STAT-6 和酪氨酸激酶 JAK3 在减数分裂和早期单倍体基因表达中的作用。使用减数分裂前期作为焦点，我们将检查关键转变点是否受到精母细胞 STAT-DNA 结合的激活和/或抑制的影响。 在减数分裂前、减数分裂前期和早期单倍体生殖细胞中，我们建议测试转录因子STAT-4和STAT-6是否将定义（a）细胞因子信号后形成的DNA结合复合物的平台特征，（b）那些阿片类药物（例如生殖细胞特异性脑啡肽启动子）和减数分裂基因（例如联会复合物）的转录控制潜力，其启动子包含 功能性和独特的 STAT 结合元件，以及（c）以特定阶段的方式介导生殖细胞和支持细胞（例如体细胞脑啡肽启动子和阿片受体）之间的旁分泌相互作用的分子机制。具体目标 1 和 3 中提出的研究将检验以下假设：白细胞介素 12、白细胞介素 4 和干扰素 α/γ 代表影响减数分裂基因表达和早期单倍体表型进展的正向和负向自分泌/旁分泌线索。 具体目标 2 中计划的那些研究将表征支持细胞特异性机制，该机制介导白细胞介素和阿片类生长因子促进的旁分泌相互作用。我们预计我们的研究结果将鉴定并进一步表征参与雄性种系减数分裂调节的新转录因子。 睾丸代表了一个独特的系统，可以在其中描述 JAK3 酪氨酸磷酸化的后果、发育过程中通过白细胞介素 4 和白细胞介素 12 进行的细胞间信号传导，以及 STAT-4 和 STAT-6 在基因转录中的独特作用，从而提供可能与淋巴细胞发育和免疫疾病相关的机制见解。