title: Patch clamp characterization of a non-selective cation channel of ER membranes purified from Beta vulgaris taproots.
abstract: The ER fraction from red beet taproot was purified on sucrose gradient and giant liposomes, suitable for patch clamping, were formed by dehydration-rehydration of the lipid film. Single-channel recordings on excised and attached patches revealed a large conductance (165 pS) cation (P(Cl-)/P(K+) < 0.03) channel with equal conductance and relative permeability for Na+ and K+. This non-selective cation channel was also highly permeable for Ca2+. We failed to detect any single-channel currents activated by a direct application of d-myo-inositol 1,4,5 trisphosphate, despite the fact that the ER membranes were native.
authors.affiliation: Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43, No 130, Chuburná de Hidalgo, Mérida 97200, Yucatán, México.
authors.forename: Ligia
authors.initials: L
authors.lastname: Brito-Argáez
authors.forename: Blondy
authors.initials: B
authors.lastname: Canto-Canché
authors.forename: Soledad Maria Teresa
authors.initials: SM
authors.lastname: Hernández-Sotomayor
authors.forename: Manuel
authors.initials: M
authors.lastname: Martínez-Estevez
authors.forename: Igor I
authors.initials: II
authors.lastname: Pottosin
mesh_terms: D027461:Beta vulgaris / Q000378:metabolism*; D002412:Cations; D004721:Endoplasmic Reticulum / Q000502:physiology*; D007473:Ion Channels / Q000302:isolation & purification / Q000502:physiology*; D008081:Liposomes; D018408:Patch-Clamp Techniques; D018517:Plant Roots / Q000378:metabolism*
chemical_list: D002412:Cations; D007473:Ion Channels; D008081:Liposomes