A high‐conductance voltage‐dependent multistate Ca2+ channel found in sea urchin and mouse spermatozoa

• Published in: FEBS letters 1994-01, Vol.338 (1), p.23-26
• Main Authors: Beltrán, C., Darszon, A., Labarca, P., Liévano, A.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Ca2+ channel; Calcium Channels - metabolism; Cell membranes. Ionic channels. Membrane pores; Cell structures and functions; Electrophysiology; Fundamental and applied biological sciences. Psychology; In Vitro Techniques; Ion Channel Gating; Lipid Bilayers; Male; Mice; Molecular and cellular biology; Sea Urchins; Sperm ion channel; Spermatozoa; Spermatozoa - metabolism
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(94)80109-6

Ion fluxes through poorly understood channel‐mediated mechanisms participate in the interaction between spermatozoa and egg. Previously, we reported the characterization in planar bilayers of a high conductance Ca2+‐selective, voltage‐dependent multistate channel from S. purpuratus sea urchin sperm plasma membranes [14]. Here we show that this ion channel can be directly transferred to planar lipid bilayers upon sperm addition, from sea urchin [S. purpuratus and L. pictus) and from mouse. We found that spermatozoa from these species posses a conspicuous Ca2+‐selective, high conductance, multi‐state, voltage‐dependent channel, which displays similar voltage dependence and equal PBa2+/PK + ~4 in the three species. The presence of this Ca2+ channel in such diverse species suggests it plays a relevant role in sperm physiology. The high sensitivity of planar bilayers to detect single ion channels can now be used to study ion channel regulation and gamete interaction.