A conserved glutamate is important for slow inactivation in K+ channels
2000 (English)In: Neuron, ISSN 0896-6273, E-ISSN 1097-4199, Vol. 27, no 3, 573-583 p.Article in journal (Refereed) Published
Voltage-gated ion channels undergo slow inactivation during prolonged depolarizations. We investigated the role of a conserved glutamate at the extracellular end of segment 5 (S5) in slow inactivation by mutating it to a cysteine (E418C in Shaker). We could lock the channel in two different conformations by disulfide-linking 418C to two different cysteines, introduced in the Pore-S6 (P-S6) loop. Our results suggest that E418 is normally stabilizing the open conformation of the slow inactivation gate by forming hydrogen bonds with the P-S6 loop. Breaking these bonds allows the P-S6 loop to rotate, which closes the slow inactivation gate. Our results also suggest a mechanism of how the movement of the voltage sensor can induce slow inactivation by destabilizing these bonds.
Place, publisher, year, edition, pages
Elsevier Science B.V., Amsterdam. , 2000. Vol. 27, no 3, 573-583 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-59768DOI: 10.1016/S0896-6273(00)00067-2ISI: 89601300020PubMedID: 11055439OAI: oai:DiVA.org:liu-59768DiVA: diva2:353385