Zhao Changle, Liu Xiang, Liu Lei, Li Jianeng, Liu Xingyong, Tao Wenjing, Wang Deshou, Wei Jing
Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China.
Biol Reprod. 2023 Nov 15;109(5):772-784. doi: 10.1093/biolre/ioad090.
The proliferation of spermatogonia directly affects spermatogenesis and male fertility, but its underlying molecular mechanisms are poorly understood. In this study, Smoothened (Smo), the central transducer of Hedgehog signaling pathway, was characterized in medaka (Oryzias latipes), and its role and underlying mechanisms in the proliferation of spermatogonia were investigated. Smo was highly expressed in spermatogonia. In ex vivo testicular organ culture and a spermatogonial cell line (SG3) derived from medaka mature testis, Smo activation promoted spermatogonia proliferation, while its inhibition induced apoptosis. The expression of glioma-associated oncogene homolog 1 (gli1) and regulator of cell cycle (rgcc) was significantly upregulated in SG3 after Smo activation. Furthermore, Gli1 transcriptionally upregulated the expression of rgcc, and Rgcc overexpression rescued cell apoptosis caused by Smo or Gli1 inhibition. Co-immunoprecipitation assay indicated that Rgcc could interact with cyclin-dependent kinase 1 (Cdk1) to regulate the cell cycle of spermatogonia. Collectively, our study firstly reveals that Smo mediates the proliferation of spermatogonia through Gli1-Rgcc-Cdk1 axis. In addition, Smo and Gli1 are necessary of the survival of spermatogonia. This study deepens our understanding of spermatogonia proliferation and survival at the molecular level, and provides insights into male fertility control and reproductive disease treatment.
精原细胞的增殖直接影响精子发生和男性生育能力，但其潜在的分子机制尚不清楚。在本研究中，对青鳉（Oryzias latipes）中刺猬信号通路的核心转导分子 smoothened（Smo）进行了表征，并研究了其在精原细胞增殖中的作用及潜在机制。Smo在精原细胞中高表达。在体外睾丸器官培养和源自青鳉成熟睾丸的精原细胞系（SG3）中，Smo激活促进精原细胞增殖，而其抑制则诱导细胞凋亡。Smo激活后，SG3中胶质瘤相关癌基因同源物1（gli1）和细胞周期调节因子（rgcc）的表达显著上调。此外，Gli1转录上调rgcc的表达，Rgcc过表达可挽救由Smo或Gli1抑制引起的细胞凋亡。免疫共沉淀分析表明，Rgcc可与细胞周期蛋白依赖性激酶1（Cdk1）相互作用以调节精原细胞的细胞周期。总的来说，我们的研究首次揭示Smo通过Gli1-Rgcc-Cdk1轴介导精原细胞的增殖。此外，Smo和Gli1对精原细胞的存活是必需的。本研究加深了我们在分子水平上对精原细胞增殖和存活的理解，并为男性生育控制和生殖疾病治疗提供了见解。
