Chromatin and gene organization during spermatogenesis and early developement: An evolutionary perspective

精子发生和早期发育过程中的染色质和基因组织：进化视角

• 批准号: 46399-2012
• 负责人: Ausio, Juan
• 金额: $ 2.48万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568959
• 关键词: Chromatin; gene; organization; during; spermatogenesis

Spermatogenesis is a cell differentiation process leading to the formation of the male gametes (spermatozoa). The deoxyribonucleic acid (DNA) of sperm cells is associated with a set of highly basic proteins called protamines. This contrasts the rest of the body, including eggs, in which the DNA is associated with a broad spectrum of nuclear proteins such as core histones, linker histones and non-histone proteins. In both instances, the resulting protein-DNA complexes are called chromatin. During spermatogenesis, histones of chromatin from the stem cells are replaced in the mature sperm by sperm-specific histones (H), protamines (P), or protamine-like proteins (PL), which have an intermediate chemical composition between H and P. This histone replacement process is reverted during fertilization of the egg by the sperm. The molecular mechanisms involved in these chromatin rearrangements are poorly understood. The long-term objective of this research is to describe and understand the structural changes and factors involved in the chromatin modifications during spermatogenesis and after fertilization. To facilitate this, we have selected several invertebrate and vertebrate organisms, with high levels of gametes, for analysis. This research has a two-fold interest. From an applied perspective, the understanding of these chromatin transitions could enlighten society on human infertility problems, sperm competition, and speciation in other organisms. From an academic perspective, the analysis and characterization of the genes and corresponding proteins involved in these processes, in different organisms, provide a unique opportunity to study their evolution.

精子发生是导致雄性配子（精子）形成的细胞分化过程。精子细胞的脱氧核糖核酸 (DNA) 与一组称为鱼精蛋白的强碱性蛋白质相关。这与身体的其他部分（包括鸡蛋）形成鲜明对比，在鸡蛋中，DNA 与广泛的核蛋白（如核心组蛋白、连接组蛋白和非组蛋白）相关。在这两种情况下，产生的蛋白质-DNA 复合物称为染色质。 在精子发生过程中，来自干细胞的染色质组蛋白在成熟精子中被精子特异性组蛋白 (H)、鱼精蛋白 (P) 或鱼精蛋白样蛋白 (PL) 取代，这些蛋白的化学成分介于 H 和 P 之间。这种组蛋白替代过程在精子使卵子受精期间恢复。 人们对这些染色质重排所涉及的分子机制知之甚少。这项研究的长期目标是描述和理解精子发生期间和受精后染色质修饰所涉及的结构变化和因素。为了促进这一点，我们选择了几种具有高水平配子的无脊椎动物和脊椎动物进行分析。 这项研究有两个目的。从应用的角度来看，对这些染色质转变的理解可以启发社会对人类不育问题、精子竞争和其他生物体中的物种形成的认识。从学术角度来看，对不同生物体中参与这些过程的基因和相应蛋白质的分析和表征，为研究其进化提供了独特的机会。