Reaction: ATP + H2O + closed Cl- channel = ADP + phosphate + open Cl- channel
Other name(s): cystic fibrosis transmembrane conductance regulator; CFTR (gene name)
Systematic name: ATP phosphohydrolase (channel-conductance-controlling)
Comments: ABC-type (ATP-binding cassette-type) ATPase, characterized by the presence of two similar ATP-binding domains. The enzyme is found in animals, and in humans its absence brings about cystic fibrosis. Unlike most of the ABC transporters, chloride pumping is not directly coupled to ATP hydrolysis. Instead, the passive flow of anions through the channel is gated by cycles of ATP binding and hydrolysis by the ATP-binding domains. The enzyme is also involved in the functioning of other transmembrane channels.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Chen, M. and Zhang, J.T. Membrane insertion, processing, and topology of cystic fibrosis transmembrane conductance regulator (CFTR) in microsomal membranes. Mol. Membr. Biol. 13 (1996) 33-40. [PMID: 9147660]
2. Tusnady, G.E., Bakos, E., Varadi, A. and Sarkadi, B. Membrane topology distinguishes a subfamily of the ATP-binding cassette (ABC) transporters. FEBS Lett. 402 (1997) 1-3. [PMID: 9013845]
3. Sheppard, D.N. and Welsh, M.J. Structure and function of the CFTR chloride channel. Physiol. Rev. 79 (1999) S23-S45. [PMID: 9922375]
4. Hwang, T.C. and Sheppard, D.N. Gating of the CFTR Cl- channel by ATP-driven nucleotide-binding domain dimerisation. J. Physiol. 587 (2009) 2151-2161. [PMID: 19332488]