RNase H1 通过在减数分裂过程中降解 DNA-RNA 杂交体促进重组酶的募集。
RNase H1 facilitates recombinase recruitment by degrading DNA-RNA hybrids during meiosis.
机构信息
Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China.
State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Stem Cell and Regenerative Medicine Innovation Institute, Chinese Academy of Sciences, Beijing 100101, China.
出版信息
Nucleic Acids Res. 2023 Aug 11;51(14):7357-7375. doi: 10.1093/nar/gkad524.
DNA-RNA hybrids play various roles in many physiological progresses, but how this chromatin structure is dynamically regulated during spermatogenesis remains largely unknown. Here, we show that germ cell-specific knockout of Rnaseh1, a specialized enzyme that degrades the RNA within DNA-RNA hybrids, impairs spermatogenesis and causes male infertility. Notably, Rnaseh1 knockout results in incomplete DNA repair and meiotic prophase I arrest. These defects arise from the altered RAD51 and DMC1 recruitment in zygotene spermatocytes. Furthermore, single-molecule experiments show that RNase H1 promotes recombinase recruitment to DNA by degrading RNA within DNA-RNA hybrids and allows nucleoprotein filaments formation. Overall, we uncover a function of RNase H1 in meiotic recombination, during which it processes DNA-RNA hybrids and facilitates recombinase recruitment.
DNA-RNA 杂交体在许多生理过程中发挥着各种作用,但这种染色质结构在精子发生过程中是如何动态调节的,在很大程度上仍然未知。在这里,我们表明,专门降解 DNA-RNA 杂交体中 RNA 的酶——Rnaseh1 在生殖细胞中的特异性敲除,会损害精子发生并导致男性不育。值得注意的是,Rnaseh1 的敲除导致不完全的 DNA 修复和减数分裂前期 I 阻滞。这些缺陷源于合线期精母细胞中 RAD51 和 DMC1 募集的改变。此外,单分子实验表明,RNase H1 通过降解 DNA-RNA 杂交体中的 RNA 促进重组酶向 DNA 的募集,并允许核蛋白丝的形成。总的来说,我们揭示了 RNase H1 在减数分裂重组中的一个功能,在此过程中,它处理 DNA-RNA 杂交体并促进重组酶的募集。