Severed channels probe regulation of gating of cystic fibrosis transmembrane conductance regulator by its cytoplasmic domains.

ABSTRACT: Opening and closing of a CFTR Cl(-) channel is controlled by PKA-mediated phosphorylation of its cytoplasmic regulatory (R) domain and by ATP binding, and likely hydrolysis, at its two nucleotide binding domains. Functional interactions between the R domain and the two nucleotide binding domains were probed by characterizing the gating of severed CFTR channels expressed in Xenopus oocytes. Expression levels were assessed using measurements of oocyte conductance, and detailed functional characteristics of the channels were extracted from kinetic analyses of macroscopic current relaxations and of single-channel gating events in membrane patches excised from the oocytes. The kinetic behavior of wild-type (WT) CFTR channels was compared with that of split CFTR channels bearing a single cut (be

SUBMITTER: Csanady L 

PROVIDER: S-EPMC2233695 | biostudies-literature | 2000 Sep

REPOSITORIES: biostudies-literature