From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China.
§Center for Reproduction and Genetics, Suzhou Municipal Hospital, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215002, P.R. China.
Mol Cell Proteomics. 2018 Jan;17(1):31-42. doi: 10.1074/mcp.M117.066993. Epub 2017 Nov 20.
Generation of haploid gametes by meiosis is a unique property of germ cells and is critical for sexual reproduction. Leaving mitosis and entering meiosis is a key step in germ cell development. Several inducers or intrinsic genes are known to be important for meiotic initiation, but the regulation of meiotic initiation, especially at the protein level, is still not well understood. We constructed a comparative proteome profile of female mouse fetal gonads at specific time points (11.5, 12.5, and 13.5 days post coitum), spanning a critical window for initiation of meiosis in female germ cells. We identified 3666 proteins, of which 473 were differentially expressed. Further bioinformatics analysis showed that these differentially expressed proteins were enriched in the mitochondria, especially in the electron transport chain and, notably, 9 proteins in electron transport chain Complex I were differentially expressed. We disrupted the mitochondrial electron transport chain function by adding the complex I inhibitor, rotenone to 11.5 days post coitum female gonads cultured in This treatment resulted in a decreased proportion of meiotic germ cells, as assessed by staining for histone γH2AX. Rotenone treatment also caused decreased ATP levels, increased reactive oxygen species levels and failure of the germ cells to undergo premeiotic DNA replication. These effects were partially rescued by adding Coenzyme Q10. Taken together, our results suggested that a functional electron transport chain is important for meiosis initiation. Our characterization of the quantitative proteome of female gonads provides an inventory of proteins, useful for understanding the mechanisms of meiosis initiation and female fertility.
通过减数分裂产生单倍体配子是生殖细胞的独特特性，对有性繁殖至关重要。离开有丝分裂进入减数分裂是生殖细胞发育的关键步骤。已知有几个诱导物或内在基因对减数分裂的起始很重要，但减数分裂起始的调节，特别是在蛋白质水平上，仍然知之甚少。我们构建了雌性小鼠胎儿性腺在特定时间点（受精后 11.5、12.5 和 13.5 天）的比较蛋白质组图谱，跨越了雌性生殖细胞减数分裂起始的关键窗口。我们鉴定了 3666 种蛋白质，其中 473 种表达差异。进一步的生物信息学分析表明，这些差异表达的蛋白质富含在线粒体中，特别是在线粒体电子传递链中，值得注意的是，电子传递链复合物 I 中的 9 种蛋白质表达差异。我们通过添加复合物 I 抑制剂鱼藤酮来破坏线粒体电子传递链功能，在受精后 11.5 天培养的雌性性腺中进行处理。这种处理导致减数分裂生殖细胞的比例降低，通过对组蛋白 γH2AX 的染色来评估。鱼藤酮处理还导致 ATP 水平降低、活性氧水平升高以及生殖细胞无法进行减数分裂前的 DNA 复制。用辅酶 Q10 部分挽救了这些影响。总之，我们的结果表明，功能正常的电子传递链对减数分裂的起始很重要。我们对雌性性腺的定量蛋白质组的特征描述提供了一个蛋白质清单，有助于理解减数分裂起始和女性生育能力的机制。
