Gating and regulation of connexin 43 (U43) hemichannels

Simple item page
dc.contributor.authorContreras, JE
dc.contributor.authorSáez, JC
dc.contributor.authorBukauskas, FF
dc.contributor.authorBennett, MVL
dc.date.accessioned2025-01-21T01:08:57Z
dc.date.available2025-01-21T01:08:57Z
dc.date.issued2003
dc.description.abstractConnexin 43 (Cx43) nonjunctional or "unapposed" hemichannels can open under physiological or pathological conditions. We characterize hemichannels comprised of Cx43 or Cx43-EGFP (Cx43 with enhanced GFP fused to the C terminus) expressed in HeLa cells. Channel opening was induced at potentials greater than +60 mV. Open probability appeared to be very low. No comparable opening was detected in the parental, nontransfected HeLa cells. Conductance of fully open single hemichannels was approximate to220 pS, which is approximately double that of Cx43 cell-cell channels. Cx43 hemichannels exhibited two types of gating: fast transitions (<1 ms) between the fully open state and a substate of approximate to75 pS and slow transitions (>5 ms) between either open state and the fully closed state. Cx43-EGFP hemichannels exhibited only slow transitions (>5 ms) between closed and fully open states. These properties resemble those of the corresponding Cx43 and Cx43-EGFP cell-cell channels. Cx43 with EGFP on the N terminus (EGFP-Cx43) inserted into the surface and formed plaques but did not form hemichannels or cell-cell channels. Hemichannel blockers, 18beta-glycyrrhetinic acid or La3+, blocked depolarization-induced currents. Uptake of ethidium bromide (i) was faster in Cx43 and Cx43-EGFP than parental and EGFP-Cx43 cells, (it) was directly correlated with Cx43-EGFP expression, (M) was reduced by hemichannel blockers, and (iv) occurred at the same low rate in EGFP-Cx43 and parental cells. Although hemichannel opening was not detected electrophysiologically at the resting potential, infrequent or brief opening could account for ethidium bromide uptake. Opening of Cx43 hemichannels may mediate normal signaling or be deleterious.
dc.description.funderNINDS NIH HHS
dc.fuente.origenWOS
dc.identifier.doi10.1073/pnas.1434298100
dc.identifier.issn0027-8424
dc.identifier.urihttps://doi.org/10.1073/pnas.1434298100
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/96528
dc.identifier.wosidWOS:000185685700040
dc.issue.numero20
dc.language.isoen
dc.pagina.final11393
dc.pagina.inicio11388
dc.revistaProceedings of the national academy of sciences of the united states of america
dc.rightsacceso restringido
dc.subjectgap junction
dc.subjectconnexon
dc.subjectdye uptake
dc.subjectpermeation
dc.subject.ods03 Good Health and Well-being
dc.subject.odspa03 Salud y bienestar
dc.titleGating and regulation of connexin 43 (U43) hemichannels
dc.typeartículo
dc.volumen100
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas