Acid-sensitive TWIK and TASK channels show dynamic ion selectivity
نویسندگان
چکیده
Background: Two-pore domain K channels mediate background K conductance and regulate cellular function. Results: Low extracellular pH (pHo) significantly increases the Na to K relative permeability of TWIK-1, TASK-1, and TASK-3 K channels. Conclusion: TWIK-1, TASK-1, and TASK-3 channels change ion selectivity in lowered pHo. Significance: The findings provide insights on the mechanism of regulation of acid-sensitive K2P channels by low pHo.
منابع مشابه
Acid-sensitive TWIK and TASK two-pore domain potassium channels change ion selectivity and become permeable to sodium in extracellular acidification.
Two-pore domain K(+) channels (K2P) mediate background K(+) conductance and play a key role in a variety of cellular functions. Among the 15 mammalian K2P isoforms, TWIK-1, TASK-1, and TASK-3 K(+) channels are sensitive to extracellular acidification. Lowered or acidic extracellular pH (pH(o)) strongly inhibits outward currents through these K2P channels. However, the mechanism of how low pH(o)...
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