biostudies-literatureUnknown11Kijima T<b>Introduction:</b> Sperm motility, including chemotactic behavior, is regulated by changes in the intracellular Ca²⁺ concentration, and the sperm-specific Ca²⁺ channel CatSper has been shown to play an important role in the regulation of intracellular Ca²⁺. In particular, in mammals, CatSper is the only functional Ca²⁺ channel in the sperm, and mice deficient in the genes comprising the pore region of the Ca²⁺ channel are infertile due to the inhibition of sperm hyperactivation. CatSper is also thought to be involved in sea urchin chemotaxis. In contrast, in ascidian <i>Ciona intestinalis</i>, SAAF, a sperm attractant, interacts with Ca²⁺/ATPase, a Ca²⁺ pump. Although the existence of <i>CatSper</i> genes has been reported, it is not clear whether CatSper is a functional Ca²⁺ channel in sperm. <b>Results:</b> We showed that CatSper is present in the sperm flagella of <i>C. intestinalis</i> as in mammalian species, although a small level of gene expression was found in other tissues. The spermatozoa of <i>CatSper3</i> KO animals were significantly less motile, and some motile sperms did not show any chemotactic behavior. These results suggest that CatSper plays an important role in ascidians and mammals, and is involved in spermatogenesis and basic motility mechanisms.Frontiers in cell and developmental biology1136537https://www.ebi.ac.uk/biostudies/studies/S-EPMC10652287biostudies-literatureCatSper mediates not only chemotactic behavior but also the motility of ascidian sperm.PMC10652287Yoshida MKurokawa DSasakura YOgasawara MKijima TAratake SYoshida KfalseCatSper mediates not only chemotactic behavior but also the motility of ascidian sperm.<b>Introduction:</b> Sperm motility, including chemotactic behavior, is regulated by changes in the intracellular Ca²⁺ concentration, and the sperm-specific Ca²⁺ channel CatSper has been shown to play an important role in the regulation of intracellular Ca²⁺. In particular, in mammals, CatSper is the only functional Ca²⁺ channel in the sperm, and mice deficient in the genes comprising the pore region of the Ca²⁺ channel are infertile due to the inhibition of sperm hyperactivation. CatSper is also thought to be involved in sea urchin chemotaxis. In contrast, in ascidian <i>Ciona intestinalis</i>, SAAF, a sperm attractant, interacts with Ca²⁺/ATPase, a Ca²⁺ pump. Although the existence of <i>CatSper</i> genes has been reported, it is not clear whether CatSper is a functional Ca²⁺ channel in sperm. <b>Results:</b> We showed that CatSper is present in the sperm flagella of <i>C. intestinalis</i> as in mammalian species, although a small level of gene expression was found in other tissues. The spermatozoa of <i>CatSper3</i> KO animals were significantly less motile, and some motile sperms did not show any chemotactic behavior. These results suggest that CatSper plays an important role in ascidians and mammals, and is involved in spermatogenesis and basic motility mechanisms.2023-01-01T00:00:00Z20232024-11-06T07:00:39.845Z2024-11-06T07:00:39.845ZS-EPMC106522873802091510.3389/fcell.2023.1136537