Expression of Testis-specific Serine/Threonine Kinases during the Reproductive and Nonreproductive Seasons and Their Localization in Mature Spermatozoa of Tree Shrews (Tupaia belangeri)

Comp Med. 2023 Aug 7. doi: 10.30802/AALAS-CM-23-000043. Online ahead of print.ABSTRACTTree shrews display obvious reproductive cycles, and sexually mature male tree shrews produce little or no sperm withextremely low motility during the nonreproductive season; the mechanism underlying this phenomenon remains unknown.Because testis-specific serine/threonine kinases (TSSK) are specifically expressed in the testis and male germ cells of mammals,we hypothesized that they may have an important role in spermatogenesis or sperm function regulation in tree shrews.In addition, the expression, distribution, subcellular localization, and dynamic changes of TSSK in tree shrew sperm areunclear. Here we show that during the reproductive season, the seminiferous tubules were significantly larger as comparedwith the nonreproductive season and contained mature sperm and other germ cells. The mRNA expression of Tssk genes intestis was significantly higher than that in other tissues, and the mRNA level in the testis during the reproductive season wassignificantly higher than that in nonreproductive season. In addition, the mRNA level of Tssk3 in the testis and sperm wassignificantly higher than that of other members. Specifically, Tssk1 mRNA was distributed in the acrosome and throughout theflagellum of tree shrew sperm, Tssk2 was present in the acrosome, Tssk3 was localized to postacrosomal region and relocated to the main part of the flagellum after capacitation, and Tssk6 was distributed in ...

Source: Comparative Medicine - August 7, 2023 Category: Zoology Authors: Xia Tan Xin Zhang Xiang Li Minghua Yang Source Type: research