Structure of the Transmembrane Regions of a Bacterial Cyclic Nucleotide-Regulated Channel

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Proceedings of the National Academy of Sciences of the USA

DOI:https://doi.org/10.1073/pnas.0711533105· OSTI ID:959496

Clayton, G; Latieri, S; Heginbotham, L; Unger, V; Morais-Cabral, J

The six-transmembrane helix (6 TM) tetrameric cation channels form the largest ion channel family, some members of which are voltage-gated and others are not. There are no reported channel structures to match the wealth of functional data on the non-voltage-gated members. We determined the structure of the transmembrane regions of the bacterial cyclic nucleotide-regulated channel MlotiK1, a non-voltage-gated 6 TM channel. The structure showed how the S1-S4 domain and its associated linker can serve as a clamp to constrain the gate of the pore and possibly function in concert with ligand-binding domains to regulate the opening of the pore. The structure also led us to hypothesize a new mechanism by which motions of the S6 inner helices can gate the ion conduction pathway at a position along the pore closer to the selectivity filter than the canonical helix bundle crossing.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 959496
• Report Number(s): BNL--82482-2009-JA
• Journal Information: Proceedings of the National Academy of Sciences of the USA, Journal Name: Proceedings of the National Academy of Sciences of the USA Journal Issue: 5 Vol. 105; ISSN PNASA6; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
99 GENERAL AND MISCELLANEOUS
BACTERIA
CATIONS
DATA
NUCLEOTIDES
PORE STRUCTURE
national synchrotron light source