Heterotypic gap junction channels as voltage-sensitive valves for intercellular signaling.

ABSTRACT: Gap junction (GJ) channels assembled from connexin (Cx) proteins provide a structural basis for direct electrical and metabolic cell-cell communication. By combining fluorescence imaging and dual whole-cell voltage clamp methods, we demonstrate that in response to transjunctional voltage (Vj) Cx43/Cx45 heterotypic GJs exhibit both Vj-gating and dye transfer asymmetries. The later is affected by ionophoresis of charged fluorescent dyes and voltage-dependent gating. We demonstrate that small differences in resting (holding) potentials of communicating cells can fully block (at relative negativity on Cx45 side) or enhance (at relative positivity on Cx45 side) dye transfer. Similarly, series of high frequency Vj pulses resembling bursts of action potentials (APs) can fully block or increase th

SUBMITTER: Palacios-Prado N 

PROVIDER: S-EPMC2736430 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature