The role of cleaved-protamine 2 in sperm chromatin dynamics.

裂解鱼精蛋白 2 在精子染色质动力学中的作用。

• 批准号: 396780147
• 负责人: Dr. Lena Arevalo
• 金额: --
• 依托单位: Institut für Pathologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/396780147?language=en
• 关键词: role; cleaved; protamine; sperm; chromatin

Studies on reproduction, be it in medical or evolutionary contexts, have always put a great emphasis on the processes involved in sperm development and function. This is mainly due to the role these processes play in cases of male infertility and the strong evolutionary pressures on underlying genes. The packaging of paternal DNA in the sperm cell nucleus and its protection during transit is a crucial aspect of correct sperm function. Successful fertilization and embryo survival depend on the correct execution of the complete reorganization of paternal chromatin during spermatogenesis, a process unique to sperm cells. Condensation by histones does not provide the size reduction and shielding necessary for transport through the male and female reproductive tracts. Histones are therefore replaced by testes specific protamines during chromatin reorganization. The two mammalian protamines (PRM1 and PRM2) have been studied extensively in the context of male infertility as well as sperm head phenotype and are crucial to sperm function. Yet there is an essential aspect that still is a missing piece in the puzzle of sperm chromatin condensation: the processing of PRM2. While otherwise very similar to PRM1, PRM2 is produced as a longer pre-protein and processed, separating the C-terminal (DNA binding) part of PRM2 and the highly different and functionally unexplored N-terminal domain, which is cleaved off and not part of the final chromatin package in mature sperm (cleaved-PRM2). It has been shown that this processing is imperative for proper chromatin condensation and the prevention of DNA damage, yet our knowledge about this domain and its function is rudimentary at best. We propose to study the function and role of cleaved-PRM2 and its interaction with other key proteins in the regulation and execution of chromatin condensation during spermiogenesis in a mouse model. The proposed study is designed as an interdisciplinary approach, combining CRISPR/Cas gene editing and comparative evolutionary methodologies. This will give us the unique opportunity to gain insight into the molecular basis of the organization and protection of the paternal genome and advance our understanding of the involvement of protamine-mediated DNA reorganization in male infertility.

生殖研究，无论是在医学还是进化背景下，一直非常重视精子发育和功能的过程。这主要是由于这些过程在男性不育症中的作用以及对潜在基因的强大进化压力。精子细胞核中父亲DNA的包装及其在运输过程中的保护是正确精子功能的一个重要方面。成功的受精和胚胎存活取决于在精子发生过程中父亲染色质的完全重组的正确执行，这是精子细胞特有的过程。组蛋白的浓缩不能提供通过雄性和雌性生殖道运输所需的尺寸减小和屏蔽。因此，在染色质重组过程中，组蛋白被睾丸特异性鱼精蛋白取代。两种哺乳动物精蛋白（PRM 1和PRM 2）已被广泛研究的背景下，男性不育症以及精子头表型，是至关重要的精子功能。然而，在精子染色质凝聚的谜团中，有一个重要的方面仍然是缺失的部分：PRM 2的加工。虽然在其他方面与PRM 1非常相似，但PRM 2作为较长的前蛋白产生并加工，将PRM 2的C-末端（DNA结合）部分与高度不同且功能上未探索的N-末端结构域分离，N-末端结构域被切割掉，而不是成熟精子中最终染色质包装的一部分（切割的-PRM 2）。研究表明，这种加工对于正确的染色质浓缩和防止DNA损伤至关重要，但我们对该结构域及其功能的了解充其量只是初步的。我们建议在小鼠模型中研究切割的PRM 2的功能和作用及其与其他关键蛋白质在精子发生过程中的调节和执行染色质凝聚的相互作用。这项研究是一种跨学科的方法，结合了CRISPR/Cas基因编辑和比较进化方法。这将使我们有独特的机会深入了解父系基因组的组织和保护的分子基础，并促进我们对鱼精蛋白介导的DNA重组参与男性不育的理解。