丝氨酸蛋白酶参与精子成熟、获能以及顶体反应等一系列重要的精子功能调节过程，组成精卵融合过程中顶体囊泡释放的一组酶类关键蛋白，促进精子通过卵母细胞周围的积云细胞进入透明带。顶体酶是已经证明参与透明带渗透使卵子受精所必需的关键丝氨酸蛋白酶。而最新研究表明丝氨酸蛋白酶家族成员广泛的参与精子转运、储存和激活过程中的功能调节，本项目在前期工作基础上通过CRISPR/Cas9系统靶向敲除家蚕丝氨酸蛋白酶BmSer2和BmSer14基因后发现非常有趣的突变体表型，在不影响成虫交配、繁殖行为的基础上，可以特异性的导致子代性别特异性不育，家蚕BmSer2基因突变会导致子代雄性特异性不育、而BmSer14基因突变则导致子代雌性特异性不育，由此我们成功构建性别特异性不育突变品系，在此基础上我们将对由这两个基因突变导致的不育机理展开深入研究，探究丝氨酸蛋白酶参与调节精子功能方面的具体作用方式和上下游关系。

Serine proteases are involved in a series of important sperm function regulation processes, such as sperm maturation, sperm capacitation, sperm acrosome reaction and so on. They constitute a group of key enzymes released by acrosome vesicles during sperm-egg fusion, and promote sperm to enter zona pellucida through cumulus cells around oocyte. Acrosin has been shown to be the key serine proteases necessary for zona pellucida osmosis to fertilize eggs. Recent studies have shown that members of the serine protease family are extensively involved in the regulation of sperm transport, storage and activation. Based on previous work, this project has found interesting mutant phenotypes after targeted deletion of serine protease BmSer2 and BmSer14 genes by CRISPR/Cas9 system, which can lead to sex-specific infertility in offspring, without affecting adult mating and reproductive behavior. BmSer2 gene mutation leads to male-specific infertility in offspring, and BmSer14 gene mutation leads to female-specific infertility in offspring. Therefore, we successfully constructed a mutant line of sex-specific infertility. On this basis, we will study the mechanism of infertility caused by these two gene mutations and explore serine protease family function in reproduction, and elucidate how these key factors participate in the regulation of sperm function in specific ways and upstream or downstream relationships.