MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, China.
Academic Unit of Reproductive and Developmental Medicine, University of Sheffield, United Kingdom.
Histol Histopathol. 2020 Jan;35(1):1-23. doi: 10.14670/HH-18-148. Epub 2019 Jul 10.
Long-term sperm storage is a special reproductive strategy, which can extend the time window between mating and fertilization in some animal species. Spermatozoa of the soft-shelled turtle, Pelodiscus sinensis, can be stored in the epididymis and oviduct for at least six months and one year, respectively. How spermatozoa can be stored in vivo for such a prolonged period is yet to be explained. We analyze the mechanisms that contribute to long-term sperm storage in P. sinensis, and compare them with other species from three different perspectives: the spermatozoon itself, the storage microenvironment and the interaction between the spermatozoon and microenvironment. Characteristics of soft-shelled turtle spermatozoa itself, such as the huge cytoplasmic droplet with its content of several large lipid droplets (LDs) and onion-like mitochondira, facilitate long-term sperm storage. The microenvironment of reproductive tract, involving in the secretions, structural barriers, exosomes, androgen receptors, Toll-like receptors and survival factor Bcl-2, are important for the maintenance of spermatozoa long-term storage. Sperm heads are always embedded among the oviductal cilia and even intercalate into the apical hollowness of the ciliated cells, indicating that the ciliated cells support the stored spermatozoa. RNA seq is firstly used to detect the molecular mechanism of sperm storage, which shows that autophagy, apoptosis and immune take part in the long-term sperm storage in this species.
长期精子储存是一种特殊的生殖策略，可以延长一些动物物种交配和受精之间的时间窗口。中华鳖的精子可以在附睾和输卵管中分别储存至少 6 个月和 1 年。精子如何能够在体内储存如此长的时间，目前仍有待解释。我们分析了中华鳖精子长期储存的机制，并从三个不同的角度与其他物种进行了比较：精子本身、储存微环境以及精子与微环境之间的相互作用。软壳龟精子本身的特征，如含有几个大脂滴的巨大细胞质滴和洋葱状的线粒体，有利于长期精子储存。生殖道的微环境，包括分泌物、结构屏障、外泌体、雄激素受体、Toll 样受体和生存因子 Bcl-2，对精子的长期储存是重要的。精子头部始终嵌入输卵管纤毛之间，甚至插入纤毛细胞的顶端凹陷处，表明纤毛细胞支持储存的精子。首次使用 RNA seq 检测精子储存的分子机制，表明自噬、凋亡和免疫参与了该物种的长期精子储存。
