Distinct gating mechanisms revealed by the structures of a multi-ligand gated K(+) channel.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 23240087.
- Also identified by DOI 10.7554/eLife.00184 and PMC identifier 3510474.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The gating ring-forming RCK domain regulates channel gating in response to various cellular chemical stimuli in eukaryotic Slo channel families and the majority of ligand-gated prokaryotic K(+) channels and transporters. Here we present structural and functional studies of a dual RCK-containing, multi-ligand gated K(+) channel from Geobacter sulfurreducens, named GsuK. We demonstrate that ADP and NAD(+) activate the GsuK channel, whereas Ca(2+) serves as an allosteric inhibitor. Multiple crystal structures elucidate the structural basis of multi-ligand gating in GsuK, and also reveal a unique ion conduction pore with segmented inner helices. Structural comparison leads us to propose a novel pore opening mechanics that is distinct from other K(+) channels.DOI:http://dx.doi.org/10.7554/eLife.00184.001.
Medical subject headings
- Bacterial Proteins
- Calcium
- Geobacter
- Ligand-Gated Ion Channels
- Potassium Channels