Cystic fibrosis gene encodes a cAMP-dependent chloride channel in heart.

AUTOR(ES)

Hart, P

RESUMO

cAMP-dependent chloride channels in heart contribute to autonomic regulation of action potential duration and membrane potential and have been inferred to be due to cardiac expression of the epithelial cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. In this report, a cDNA from rabbit ventricle was isolated and sequenced, which encodes an exon 5 splice variant (exon 5-) of CFTR, with >90% identity to human CFTR cDNA present in epithelial cells. Expression of this cDNA in Xenopus oocytes gave rise to robust cAMP-activated chloride currents that were absent in control water-injected oocytes. Antisense oligodeoxynucleotides directed against CFTR significantly reduced the density of cAMP-dependent chloride currents in acutely cultured myocytes, thereby establishing a direct functional link between cardiac expression of CFTR protein and an endogenous chloride channel in native cardiac myocytes.

Documentos Relacionados

• Intracellular Na+ modulates the cAMP-dependent regulation of ion channels in the heart.
• On the question of translocation of heart cAMP-dependent protein kinase.
• A dual role for the cAMP-dependent protein kinase in tyrosine hydroxylase gene expression.
• cAMP-dependent phosphorylation of bovine lens alpha-crystallin.
• Distinct stoichiometry of BKCa channel tetramer phosphorylation specifies channel activation and inhibition by cAMP-dependent protein kinase