Li Taotao, Wang Huihui, Luo Ruirui, An Xuejiao, Li Qiao, Su Manchun, Shi Huibin, Chen Haolin, Zhang Yong, Ma Youji
College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China.
Gansu Key Laboratory of Animal Generational Physiology and Reproductive Regulation, Lanzhou, China.
Front Vet Sci. 2022 Jul 15;9:923789. doi: 10.3389/fvets.2022.923789. eCollection 2022.
Testis has an indispensable function in male reproduction of domestic animals. Tibetan sheep () is a locally adapted breed of sheep raised in the Qinghai-Tibet Plateau, with outsized roles in providing the livelihood for millions of residents. Nevertheless, less is known on how protein expression and their functional roles in developmental testes of such breed limit their use in breeding efforts. In this study, we obtained comprehensive protein profiles from testes of Tibetan sheep at three developmental stages (including pre-puberty, post-puberty, and adulthood) using data-independent acquisition-based proteomic strategy to quantitatively identify the differentially abundant proteins (DAPs) associated with testicular development and function and to unravel the molecular basis of spermatogenesis. A total of 6,221 proteins were differentially expressed in an age-dependent manner. The reliability of the gene expression abundance was corroborated by quantitative PCR and targeted parallel reaction monitoring. These DAPs were significantly enriched to biological processes concerning spermatid development and sperm deformation, mitosis, glycolytic process, cell-cell/extracellular matrix (ECM) junctions, cell proliferation, apoptosis, and migration and to the pathways including, developmental process and sexual reproduction-related (such as VEGF, estrogen, insulin, GnRH, Hippo, PI3K-Akt, mTOR, MAPK, and AMPK), and testicular cell events-related pathways (such as tight/gap/adherens junctions, ECM-receptor interaction, regulation of actin cytoskeleton, glycolysis, cell cycle, and meiosis). Based on these bioinformatics analysis, we constructed four protein-protein interaction network, among which the proteins are involved in mitosis, meiosis, spermiogenesis, and testicular microenvironment, respectively. Altogether, these bioinformatics-based sequencing results suggest that many protein-coding genes were expressed in a development-dependent manner in Tibetan sheep testes to contribute to the testicular cell development and their surrounding microenvironment remodeling at various stages of spermatogenesis. These findings have important implications for further understanding of the mechanisms underlying spermatogenesis in sheep and even other plateau-adapted animals.
睾丸在雄性家畜繁殖中具有不可或缺的作用。藏羊（）是青藏高原地区适应本地环境的绵羊品种，在为数百万居民提供生计方面发挥着重要作用。然而，关于该品种发育中的睾丸中蛋白质表达及其功能作用如何限制其在育种工作中的应用，我们了解得还较少。在本研究中，我们采用基于数据非依赖采集的蛋白质组学策略，从藏羊三个发育阶段（包括青春期前、青春期后和成年期）的睾丸中获得了全面的蛋白质谱，以定量鉴定与睾丸发育和功能相关的差异丰富蛋白质（DAPs），并揭示精子发生的分子基础。共有6221种蛋白质以年龄依赖性方式差异表达。基因表达丰度的可靠性通过定量PCR和靶向平行反应监测得到了证实。这些DAPs显著富集于与精子细胞发育、精子变形、有丝分裂、糖酵解过程、细胞 - 细胞/细胞外基质（ECM）连接、细胞增殖、凋亡和迁移相关的生物学过程，以及包括发育过程和性繁殖相关（如VEGF、雌激素、胰岛素、GnRH、Hippo、PI3K - Akt、mTOR、MAPK和AMPK）以及睾丸细胞事件相关途径（如紧密/间隙/黏附连接、ECM - 受体相互作用、肌动蛋白细胞骨架调节、糖酵解、细胞周期和减数分裂）的途径。基于这些生物信息学分析，我们构建了四个蛋白质 - 蛋白质相互作用网络，其中的蛋白质分别参与有丝分裂、减数分裂、精子发生和睾丸微环境。总之，这些基于生物信息学的测序结果表明，许多蛋白质编码基因在藏羊睾丸中以发育依赖性方式表达，有助于在精子发生的各个阶段促进睾丸细胞发育及其周围微环境重塑。这些发现对于进一步理解绵羊乃至其他高原适应动物精子发生的潜在机制具有重要意义。
