AUTHOR=Kijima Taiga , Kurokawa Daisuke , Sasakura Yasunori , Ogasawara Michio , Aratake Satoe , Yoshida Kaoru , Yoshida Manabu 

TITLE=CatSper mediates not only chemotactic behavior but also the motility of ascidian sperm

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=Volume 11 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2023.1136537

DOI=10.3389/fcell.2023.1136537

ISSN=2296-634X

ABSTRACT=Introduction: sperm motility, including chemotactic behavior, is regulated by changes in intracellular Ca 2+ concentration, and the sperm-specific Ca 2+ channel CatSper has been shown to play an important role in the regulation of intracellular Ca 2+ . In particular, in mammals, CatSper is the only functional Ca 2+ channel in the sperm, and mice that lack the genes that make up the pore region of the Ca 2+ channel are infertile due to the inhibition of sperm hyperactivation. CatSper is also thought to be involved in sea urchin chemotaxis. In contrast, in the ascidian Ciona intestinalis, SAAF, a sperm attractant, interacts with Ca 2+ /ATPase, a Ca 2+ pump. Although the existence of Catsper genes has been reported, it is not clear whether CatSper is a functional Ca 2+ channel in sperm. Results: we showed that CatSper is present in the sperm flagella of C. intestinalis as in mammalian species, although a small level of gene expression was found in other tissues. The