In mammals, the generation of sperm cells capable of fertilization is a highly complex process including spermatogenesis in the testis and maturation in the epididymis. In our previous study, we have demonstrated that FAM71D (Family with sequence similarity 71, member D), which could interact with calmodulin, was highly expressed in human and mouse testis. To investigate the physiological role of FAM71D in spermatogenesis, we next generate Fam71d loss-of-function mouse model using CRISPR/Cas9 technology. We performed immunofluorescence and RT-qPCR to examine the protein and mRNA expression in testicular cells. We found that FAM71D was predominantly localized in the round and elongated spermatids. And FAM71D KO mice displayed normal development of germ cell and fertility. Furthermore, testicular histology and sperm concentration showed no significant difference between WT and KO mice. These data demonstrate that FAM71D is dispensable for mouse spermatogenesis and male fertility.

中文翻译：

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FAM71D 对于小鼠的精子发生和雄性生育能力是不可或缺的

在哺乳动物中，能够受精的精子细胞的产生是一个高度复杂的过程，包括睾丸中的精子发生和附睾中的成熟。在我们之前的研究中，我们已经证明FAM71D（序列相似性71家族，成员D）可以与钙调蛋白相互作用，在人和小鼠睾丸中高表达。为了研究 FAM71D 在精子发生中的生理作用，我们接下来使用 CRISPR/Cas9 技术生成 Fam71d功能丧失小鼠模型。我们进行了免疫荧光和 RT-qPCR 来检查睾丸细胞中的蛋白质和 mRNA 表达。我们发现 FAM71D 主要位于圆形和细长的精子细胞中。FAM71D KO小鼠表现出正常的生殖细胞发育和生育能力。此外，WT 和 KO 小鼠的睾丸组织学和精子浓度没有显着差异。这些数据表明 FAM71D 对于小鼠精子发生和雄性生育能力是不可或缺的。