title: Acute activation of Maxi-K channels (hSlo) by estradiol binding to the beta subunit.
abstract: Maxi-K channels consist of a pore-forming alpha subunit and a regulatory beta subunit, which confers the channel with a higher Ca(2+) sensitivity. Estradiol bound to the beta subunit and activated the Maxi-K channel (hSlo) only when both alpha and beta subunits were present. This activation was independent of the generation of intracellular signals and could be triggered by estradiol conjugated to a membrane-impenetrable carrier protein. This study documents the direct interaction of a hormone with a voltage-gated channel subunit and provides the molecular mechanism for the modulation of vascular smooth muscle Maxi-K channels by estrogens.
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Universidad Pompeu Fabra, C/Doctor Aiguader 80, 08003 Barcelona, Spain. miguel.valverde@cexs.upf.es
authors.forename: M A
authors.initials: MA
authors.lastname: Valverde
authors.forename: P
authors.initials: P
authors.lastname: Rojas
authors.forename: J
authors.initials: J
authors.lastname: Amigo
authors.forename: D
authors.initials: D
authors.lastname: Cosmelli
authors.forename: P
authors.initials: P
authors.lastname: Orio
authors.forename: M I
authors.initials: MI
authors.lastname: Bahamonde
authors.forename: G E
authors.initials: GE
authors.lastname: Mann
authors.forename: C
authors.initials: C
authors.lastname: Vergara
authors.forename: R
authors.initials: R
authors.lastname: Latorre
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D004594:Electrophysiology; D004958:Estradiol / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D051038:Large-Conductance Calcium-Activated Potassium Channel beta Subunits; D051036:Large-Conductance Calcium-Activated Potassium Channels; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000378:metabolism*; D024681:Potassium Channels, Calcium-Activated; D011485:Protein Binding; D012333:RNA, Messenger; D051381:Rats; D014982:Xenopus laevis
chemical_list: C494841:KCNMA1 protein, human; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D051038:Large-Conductance Calcium-Activated Potassium Channel beta Subunits; D051036:Large-Conductance Calcium-Activated Potassium Channels; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D012333:RNA, Messenger; D004958:Estradiol