A functional analysis of chromatin reorganisation during sperm morphogenesis in Drosophila

果蝇精子形态发生过程中染色质重组的功能分析

• 批准号: 5422450
• 负责人: Professorin Dr. Renate Renkawitz-Pohl
• 金额: --
• 依托单位: Arbeitsgruppe Kommunikation und Dynamik tierischer Zellen
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5422450?language=en
• 关键词: functional; analysis; chromatin; reorganisation; during

Chromatin remodelling during spermiogenesis leads to an extreme condensed state of the haploid genome in the sperm by a switch from the nucleosomal configuration to a protamine based doughnut structure in mammals. After fertilization and before zygote formation a reorganization of the paternal genome takes place to resume the nucleosomal configuration. Not much is known about this process in Drosophila, therefore we address questions of the displacement and degradation of histones, the possible role of tran sition proteins and protamines in an in vivo context in Drosophila spermiogenesis. GFP tagged versions of chromatin proteins are an excellent tool to follow chromatin reorganisation in vivo, such as the use of ahistone H2a-GFP carrying fly strain. We began to study if the mechanism of histone degradation is dependent on ubiquitin-conjugating enzymes present in the testes. As candidates for transient chromosomal proteins we analyse Don Juan, Don Juan like and CG1988. We showed the presence of a protamine lik e molecule in the chromatin at the end of spermiogenesis by an eGPF-tagged version. This and functional approaches, like screening for mutants in the respective genes, ectopic expression studies and protein analysis, will help to understand chromatin reorganization of the entire genome, needed for male fertility.

精子发生过程中的染色质重塑导致精子中单倍体基因组的极端浓缩状态，这是通过在哺乳动物中从核小体构型转换为基于鱼精蛋白的甜甜圈结构来实现的。受精后和受精卵形成前，父体基因组发生重组以恢复核小体构型。目前对果蝇精子发生的机制还知之甚少，因此我们探讨了组蛋白的置换和降解，以及转座子蛋白和鱼精蛋白在果蝇精子发生过程中的可能作用。GFP标记的染色质蛋白版本是跟踪体内染色质重组的极好工具，例如使用携带组蛋白H2 a-GFP的果蝇品系。我们开始研究组蛋白降解的机制是否依赖于睾丸中存在的泛素结合酶。作为瞬时染色体蛋白的候选者，我们分析了Don Juan、Don Juan like和CG 1988。我们用eGPF标记的方法证明了在精子发生末期的染色质中存在鱼精蛋白样分子。这种方法和功能性方法，如筛选相应基因的突变体，异位表达研究和蛋白质分析，将有助于了解男性生育所需的整个基因组的染色质重组。