Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
Insect Biochem Mol Biol. 2019 Jun;109:43-51. doi: 10.1016/j.ibmb.2019.03.012. Epub 2019 Apr 7.
The spermatogenesis of animal is essential for the reproduction and a very large number of genes participate in this procession. The Maelstrom (Mael) is identified essential for spermatogenesis in both Drosophila and mouse, though the mechanisms appear to differ. It was initially found that Mael gene is necessary for axis specification of oocytes in Drosophila, and recent studies suggested that Mael participates in the piRNA pathway. In this study, we obtained Bombyx mori Mael mutants by using a binary transgenic CRISPR/Cas9 system and analyzed the function of Mael in B. mori, a model lepidopteran insect. The results showed that BmMael is not necessary for piRNA pathway in the ovary of silkworm, whereas it might be essential for transposon elements (TEs) repression in testis. The BmMael mutation resulted in male sterility, and further analysis established that BmMael was essential for spermatogenesis. The spermatogenesis defects occurred in the elongation stage and resulted in nuclei concentration arrest. RNA-seq and qRT-PCR analyses demonstrated that spermatogenesis defects were associated with tight junctions and apoptosis. We also found that BmMael was not involved in the silkworm sex determination pathway. Our data provide insights into the biological function of BmMael in male spermatogenesis and might be useful for developing novel methods to control lepidopteron pests.
动物的精子发生对于繁殖至关重要，大量基因参与了这一过程。Maelstrom（Mael）在果蝇和小鼠中都被鉴定为精子发生所必需的，尽管其机制似乎不同。最初发现 Mael 基因对于果蝇卵母细胞的轴 Specification 是必需的，最近的研究表明 Mael 参与了 piRNA 途径。在这项研究中，我们使用二元转基因 CRISPR/Cas9 系统获得了家蚕 Mael 突变体，并分析了 Mael 在鳞翅目昆虫模型家蚕中的功能。结果表明，BmMael 在卵巢中对于 piRNA 途径不是必需的，而在睾丸中对于转座元件（TEs）的抑制可能是必需的。BmMael 突变导致雄性不育，进一步的分析表明 BmMael 对于精子发生是必需的。精子发生缺陷发生在伸长阶段，导致核浓缩阻滞。RNA-seq 和 qRT-PCR 分析表明，精子发生缺陷与紧密连接和细胞凋亡有关。我们还发现 BmMael 不参与家蚕性别决定途径。我们的数据提供了在家蚕雄性精子发生中 BmMael 的生物学功能的见解，可能有助于开发控制鳞翅目害虫的新方法。
