Mouse sperm K+ currents stimulated by pH and cAMP possibly coded by Slo3 channels.
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ABSTRACT:
SUBMITTER: Martinez-Lopez P
PROVIDER: S-EPMC2713764 | biostudies-literature | 2009 Apr
REPOSITORIES: biostudies-literature
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Mouse sperm K+ currents stimulated by pH and cAMP possibly coded by Slo3 channels.
Martínez-López Pablo P Santi Celia M CM Treviño Claudia L CL Ocampo-Gutiérrez Ana Y AY Acevedo Juan J JJ Alisio Arturo A Salkoff Lawrence B LB Darszon Alberto A
Biochemical and biophysical research communications 20090210 2
Slo3 channels belong to the high conductance Slo K+ channel family. They are activated by voltage and intracellular alkalinization, and have a K+/Na+ permeability ratio (PK/PNa) of only approximately 5. Slo3 channels have only been found in mammalian sperm. Here we show that Slo3 channels expressed in Xenopus oocytes are also stimulated by elevated cAMP levels through PKA dependent phosphorylation. Capacitation, a maturational process required by mammalian sperm to enable them to fertilize eggs, ...[more]
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