Voltage control of Ca²⁺ permeation through N-type calcium (Ca(V)2.2) channels.

ABSTRACT: Voltage-gated calcium (Ca(V)) channels deliver Ca(2+) to trigger cellular functions ranging from cardiac muscle contraction to neurotransmitter release. The mechanism by which these channels select for Ca(2+) over other cations is thought to involve multiple Ca(2+)-binding sites within the pore. Although the Ca(2+) affinity and cation preference of these sites have been extensively investigated, the effect of voltage on these sites has not received the same attention. We used a neuronal preparation enriched for N-type calcium (Ca(V)2.2) channels to investigate the effect of voltage on Ca(2+) flux. We found that the EC50 for Ca(2+) permeation increases from 13 mM at 0 mV to 240 mM at 60 mV, indicating that, during permeation, Ca(2+) ions sense the electric field. These data were nicely repr

SUBMITTER: Buraei Z 

PROVIDER: S-EPMC4144670 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature