Download MendeleyStructure of a voltage-dependent K+ channel beta subunit.
Gulbis, J.M., Mann, S., MacKinnon, R.(1999) Cell 97: 943-952
- PubMed: 10399921
- DOI: https://doi.org/10.1016/s0092-8674(00)80805-3
- Primary Citation of Related Structures:
1QRQ - PubMed Abstract:
The integral membrane subunits of many voltage-dependent potassium channels are associated with an additional protein known as the beta subunit. One function of beta subunits is to modify K+ channel gating. We have determined the structure of the conserved core of mammalian beta subunits by X-ray crystallography at 2.8 A resolution. Like the integral membrane component of K+ channels, beta subunits form a four-fold symmetric structure. Each subunit is an oxidoreductase enzyme complete with a nicotinamide co-factor in its active site. Several structural features of the enzyme active site, including its location with respect to the four-fold axis, imply that it may interact directly or indirectly with the K+ channel's voltage sensor. This structure suggests a mechanism for coupling membrane electrical excitability directly to chemistry of the cell.
Organizational Affiliation:
Laboratory of Molecular Neurobiology and Biophysics and the Howard Hughes Medical Institute, Rockefeller University, New York, New York 10021, USA.
