Conservation of the Ca2+-permeability through the voltage sensor domain of mammalian CatSper subunit

Hiroki Arima; Hidekazu Tsutsui; Yasushi Okamura

doi:10.1080/19336950.2018.1476791

Conservation of the Ca²⁺-permeability through the voltage sensor domain of mammalian CatSper subunit

Channels (Austin). 2018;12(1):240-248. doi: 10.1080/19336950.2018.1476791.

Authors

Hiroki Arima¹, Hidekazu Tsutsui^{1

2}, Yasushi Okamura^{1

3}

Affiliations

¹ a Department of Physiology , Graduate School of Medicine, Osaka University , Suita, Osaka Japan.
² b Department of Material Science , Japan Advanced Institute of Science and Technology , Nomi, Ishikawa Japan.
³ c Graduate School of Frontier Biosciences, Osaka University , Suita, Osaka Japan.

Abstract

Cation channel of Spermatozoa (CatSper) is one of the voltage-gated ion channels consisting of voltage sensor domains (VSDs) and pore-gate domains. CatSper is exclusively expressed in spermatozoa and indispensable for Ca²⁺ influx into cytosol. Recently, we have reported that the VSD of ascidian CatSper induces Ca²⁺-permeable pathways in heterologous expression systems. However, it is not known whether ion permeability through the VSD of CatSper is conserved in mammals. In the present study, electrophysiology and fluorometry in Xenopus oocytes revealed that Ca²⁺-permeable paths are also formed by expressing the VSD of murine CatSper. We also examined the permeability to monovalent cations other than Na⁺ in the VSD of ascidian CatSper.

Keywords: Cation permeability; catsper; ion channel; spermatozoa; voltage sensor domain.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Calcium / metabolism*
Calcium Channels / metabolism*
Male
Mice
Spermatozoa / metabolism*
Xenopus laevis

Substances

Calcium Channels
Calcium