Establishment and Analysis of Actin-like 7b deficient mice – a tool to study male factor infertility.

配子形成过程中的缺陷可能会阻碍受精成功，导致不育。不孕症在临床上被定义为“一种生殖系统疾病，定义为在12个月或更长时间的定期无保护性交后未能实现临床妊娠。多种因素已被描述为导致男性不育，包括遗传畸变以及环境影响。尽管如此，在37-58%的情况下，男性不育的确切原因仍然未知。为了开发男性不育症的潜在治疗策略或预测应用人工生殖技术（ART）的成功，有必要详细了解男性配子形成所涉及的基因和途径。其中，肌动蛋白样蛋白7 b（ACTL 7 b）被描述为仅在圆形和细长精子细胞中的睾丸中特异性表达。有趣的是，在一组日本不育男性患者中，检测到ACTL 7 b的4种多态性，表明ACTL 7 b在生育力中的潜在作用。此外，在沼泽布法罗精子发生的重要基因筛选中检测到ACTL 7 b，并且似乎参与控制羊肉的窝仔数。我们已经在合子中使用CRISPR-Cas9介导的基因编辑删除了Actl 7 b基因。初步结果支持ACTL 7 b是精子发生所需的假设。缺乏Actl 7 b的雄性动物是不育的，并且在精子发生期间显示发育停滞。为了充分了解观察到的表型，我们现在提出了一个详细的分析ACTL 7 b缺陷小鼠使用经典的组织学，免疫组织化学，质量。Spec和CoIP分析。有了这个，我们能够准确地描述ACTL 7 b的功能和作用的背景下，精子发生，特别是男性因素不育症的一般。

Defects during gamete formation may impede successful fertilization, resulting in infertility. Infertility is clinically defined as “a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse. Multiple factors have been described to cause male infertility including genetic aberrations as well as environmental influences. Still, in 37-58% of cases the exact cause for male infertility remains unknown. To develop potential treatment strategies for male infertility or predict the success when applying Artificial Reproduction Technologies (ART), it is necessary to get a detailed understanding of the genes and pathways involved in male gamete formation. Among others, the actin-like protein 7b (ACTL7b) is described to be specifically expressed in testes in round and elongated spermatids only. Interestingly in a cohort of Japanese infertile male patients, 4 polymorphisms in ACTL7b were detected, suggesting a potential role of ACTL7b in fertility. Further, ACTL7b was detected in a screen for genes important for spermatogenesis in swamp buffalo and seems to be involved in controlling litter size in mutton. We have deleted the Actl7b gene using CRISPR-Cas9 mediated gene editing in zygotes. Preliminary results support the hypothesis of ACTL7b being required for spermatogenesis. Male animals deficient for Actl7b are infertile and show a developmental arrest during spermiogenesis. In order to fully understand the phenotype observed, we propose now a detailed analysis of the ACTL7b deficient mice using classical histology, immunohistochemistry, Mass. Spec and CoIP analyses. With this we are able to precisely describe the function and role of ACTL7b in the context of spermiogenesis in particular and male factor infertility in general.