PRDM9 and Control of Meiotic Progression

PRDM9 和减数分裂进程的控制

• 批准号: 8915207
• 负责人: MARY ANN HANDEL
• 金额: $ 31.47万
• 依托单位: JACKSON LABORATORY
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8915207
• 关键词: Address; Affect; Biology; Cell Nucleus; Chromatin; Chromosome Pairing; Chromosomes; Complement; Congenital Abnormality; Event; Fertility; Fertility Determinant; Gametogenesis; Gene Expression Profile; Genetic; Genetic Recombination; Genetic Transcription; Genomics; Goals; Histones; Human; Knock-in Mouse; Knock-out; Lead; Mediating; Meiosis; Modeling; Modification; Molecular; Mus; Mutation; Nature; Nuclear Structure; Outcome; Pattern; Phenotype; Prophase; Proteins; Regulation; Role; SET Domain; Site; Specificity; Spermatocytes; Spermatogenesis; Spermatogonia; Staging; Sterility; Structure; Testing; Time; Transcript; Transcriptional Regulation; Untranslated RNA; base; chromatin modification; histone methyltransferase; human ZNF45 protein; mouse model; mutant; protein expression; targeted sequencing; transcriptome sequencing

PROJECT SUMMARY PROJECT D PRDM9 is an important regulator of recombination and transcription; it is uniquely expressed during meiosis; and its absence arrests meiotic progress and gametogenesis. Thus Prdm9 has evolved functionally to serve specific meiotic and gametogenic requirements; however, the full range and nature of these requirements is not known. In particular, the roles of PRDMS in the sequence of meiotic events, its pattern of expression, its relationship to meiotically relevant nuclear structures and domains, and how the structure of PRDMS mediates its varied enzymatic effects are all unknown. The broad, long-term goals of this project are to resolve these issues by using both cellular and genetic strategies to identify mechanisms of when (Aim 1), where (Aim 2) and how (Aim 3) PRDMS promotes recombination site activation, and successful meiosis and spermatogenesis. The results of Aim 1 will establish which steps in meiosis are subject to PRDMS control and whether PRDMS function is required continuously or only at specific meiotic or spermatogenic substages. Because preliminary evidence suggests that PRDMS occupancy in nuclei may be transient, this is important for determining when chromatin marks are set, when recombination site selection occurs, and when transcriptional control is possible. The results of Aim 2 will determine localization of the PRDMS protein and use both PrdmQ mutants and well established mouse meiosis mutant models to determine the extent to which PRDMS function is required for or dependent on proteins crucial for meiosis, including those mediating chromosome synapsis and recombination. The results of Aim 3 will determine which functions of PRDMS in meiosis and gametogenesis require either its histone methyltransferase activity or its transcription-regulating KRAB domain. Recent results suggest that non-coding RNAs are among the transcriptional targets of PRDMS. In cooperation with goals of Projects B and C, this aim will define PRDMS-specific genomic sequence targets and functional clusters of sequences epigenetically marked and/or with transcription regulated by specific PRDMS domains and their relationship to PRDMS-dependent recombination hotspots. Together, the results of this project will complement the other Projects by setting PRDMS function into the well-defined sequence of meiotic chromosome events, more specifically resolving the molecular basis for its multiple roles, and contributing to understanding how PRDMS fits into the larger network of proteins that control meiosis and gametogenesis. An important facet of PRDMS biology addressed by this project is that PRDMS is a major determinant of fertility; the aberrant recombination and failed meiosis that occur in its absence can lead to sterility or birth defects in humans.

项目D PRDM 9是重组和转录的重要调节因子;它在减数分裂期间独特地表达;并且它的缺失阻止减数分裂进程和配子发生。因此，Prdm 9在功能上已经进化为满足特定的减数分裂和配子发生要求;然而，这些要求的全部范围和性质尚不清楚。特别是，PRDMS在减数分裂事件序列中的作用，其表达模式，与减数分裂相关的核结构和结构域的关系，以及PRDMS的结构如何介导其不同的酶促作用都是未知的。该项目的广泛的长期目标是通过使用细胞和遗传策略来确定PRDMS何时（目标1），何地（目标2）和如何（目标3）促进重组位点激活以及成功的减数分裂和精子发生的机制来解决这些问题。目的1的结果将确定减数分裂中的哪些步骤受PRDMS控制，以及PRDMS功能是持续需要的还是仅在特定的减数分裂或精子发生亚阶段需要的。由于初步证据表明，PRDMS占用细胞核中可能是短暂的，这是重要的，以确定何时染色质标记设置，重组位点选择发生时，转录控制是可能的。目的2的结果将确定PRDMS蛋白的定位，并使用PrdmQ突变体和完善的小鼠减数分裂突变体模型来确定PRDMS功能对于减数分裂至关重要的蛋白质（包括介导染色体突触和重组的蛋白质）所需或依赖的程度。目的3的结果将确定PRDMS在减数分裂和配子发生中的哪些功能需要其组蛋白甲基转移酶活性或其转录调节KRAB结构域。最近的研究结果表明，非编码RNA是PRDMS的转录靶点之一。与项目B和C的目标合作，该目标将定义PRDMS特异性基因组序列靶标和表观遗传标记的序列的功能簇和/或具有由特异性PRDMS结构域调节的转录的序列的功能簇以及它们与PRDMS依赖性重组热点的关系。总之，该项目的结果将通过将PRDMS功能设置为减数分裂染色体事件的明确序列来补充其他项目，更具体地解决其多种作用的分子基础，并有助于理解PRDMS如何适应控制减数分裂和配子发生的更大的蛋白质网络。该项目解决的PRDMS生物学的一个重要方面是PRDMS是生育力的主要决定因素;在其缺失的情况下发生的异常重组和减数分裂失败可能导致人类不育或出生缺陷。