Abstract：
Spermatogenesis in eukaryotes is a process that occurs within a very narrow temperature threshold, typically not exceeding 36 °C. SPO11 was isolated from the temperature-sensitive mutant receptor of Saccharomyces cerevisiae and is thought to be the only protein that functions during meiosis. This suggested that SPO11 may be the key protein that influenced the temperature of spermatogenesis not exceeding 36 °C. Elevated temperatures typically damage the spermatogenic cells. Birds have a core body temperature of 41-42 °C, and their testis are located inside their bodies, providing an alternative perspective to investigate the potential impact of temperature threshold on spermatogenesis. The objective of this study was to ascertain whether elevated ambient temperatures affect spermatogenesis in birds and whether SPO11 is the key gene affecting the temperature threshold for spermatogenesis. STRA8, SCP3, SPO11, γ-H2AX, and RAD51 were all crucial components in the process of meiotic initiation, synapsis, DNA double-strand break (DSB) induction, homologous chromosome crossover recombination, and repair of DSB. In this study, 39-day-old Japanese quail were subjected to heat stress (HS) at 38 °C for 8 h per day for 3 (3d HS) and 13 (13d HS) consecutive days and analyzed the expression of meiotic signaling molecules (STRA8, SCP3, SPO11, γ-H2AX, and RAD51) using molecular biology techniques, including Immunohistochemistry (IHC), Western Blot (WB), and Real-time Quantitative Polymerase Chain Reaction (qRT-PCR). We found that spermatogenesis was normal in both groups exposed to HS. Meiotic signaling molecules were expressed normally in the 3d HS group. All detected signaling molecules were normally expressed in the 13d HS group, except for SPO11, which showed a significant increase in expression, indicating that SPO11 was temperature-sensitive. We examined the localized expression of each meiotic signaling molecule in quail testis, explored the temperature sensitivity of SPO11, and determined that quail testis can undergo normal spermatogenesis at ambient temperatures exceeding 36 °C. This study concluded that SPO11 is not the key protein influencing spermatogenesis in birds. These findings enhance our understanding of avian spermatogenesis.
摘要：
真核生物的精子发生是一个在非常窄的温度阈值内发生的过程，通常不超过36°C。SPO11是从酿酒酵母的温度敏感突变受体中分离出来的，被认为是减数分裂过程中唯一起作用的蛋白质。这表明SPO11可能是影响精子发生温度不超过36°C的关键蛋白。升高的温度通常会损害生精细胞。鸟类的核心体温为41-42°C，他们的睾丸位于他们体内，提供了另一种观点来研究温度阈值对精子发生的潜在影响。这项研究的目的是确定环境温度升高是否会影响鸟类的精子发生，以及SPO11是否是影响精子发生温度阈值的关键基因。STRA8,SCP3,SPO11,γ-H2AX,RAD51都是减数分裂启动过程中的关键成分，突触，DNA双链断裂(DSB)诱导,同源染色体交叉重组，并修复DSB。在这项研究中,39天大的日本鹌鹑在38°C下每天接受8小时的热应激（HS），连续3天（3dHS）和13天（13dHS），并分析减数分裂信号分子的表达（STRA8，SCP3，SPO11，γ-H2AX，和RAD51）使用分子生物学技术，包括免疫组织化学（IHC），西部印迹（WB），和实时定量聚合酶链反应(qRT-PCR)。我们发现暴露于HS的两组精子发生均正常。减数分裂信号分子在3dHS组中正常表达。所有检测到的信号分子在13dHS组中正常表达，除了SPO11，其表达显着增加，表明SPO11对温度敏感。我们检查了每种减数分裂信号分子在鹌鹑睾丸中的局部表达，探索SPO11的温度敏感性，并确定鹌鹑睾丸可以在超过36°C的环境温度下进行正常的精子发生。这项研究得出结论，SPO11不是影响鸟类精子发生的关键蛋白。这些发现增强了我们对禽类精子发生的理解。
