This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

5k7l

From Proteopedia

Jump to: navigation, search

Single particle cryo-EM structure of the voltage-gated K+ channel Eag1 bound to the channel inhibitor calmodulin

5k7l, resolution 3.78Å

Structural highlights

5k7l is a 2 chain structure with sequence from Homo sapiens and Rattus norvegicus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 3.78Å
Ligands:
Experimental data:	Check to display Experimental Data
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

KCNH1_RAT Pore-forming (alpha) subunit of a voltage-gated delayed rectifier potassium channel. Channel properties may be modulated by subunit assembly, but not by cyclic nucleotides (By similarity). Mediates IK(NI) current in myoblasts (By similarity). Involved in the regulation of cell proliferation and differentiation, as adipogenic and osteogenic differentiation in bone marrow-derived mesenchymal stem cells (MSCs) (By similarity).[UniProtKB:O95259][UniProtKB:Q60603]

Publication Abstract from PubMed

Voltage-gated potassium (K(v)) channels are gated by the movement of the transmembrane voltage sensor, which is coupled, through the helical S4-S5 linker, to the potassium pore. We determined the single-particle cryo-electron microscopy structure of mammalian K(v)10.1, or Eag1, bound to the channel inhibitor calmodulin, at 3.78 angstrom resolution. Unlike previous K(v) structures, the S4-S5 linker of Eag1 is a five-residue loop and the transmembrane segments are not domain swapped, which suggest an alternative mechanism of voltage-dependent gating. Additionally, the structure and position of the S4-S5 linker allow calmodulin to bind to the intracellular domains and to close the potassium pore, independent of voltage-sensor position. The structure reveals an alternative gating mechanism for K(v) channels and provides a template to further understand the gating properties of Eag1 and related channels.

Structure of the voltage-gated K(+) channel Eag1 reveals an alternative voltage sensing mechanism.,Whicher JR, MacKinnon R Science. 2016 Aug 12;353(6300):664-9. doi: 10.1126/science.aaf8070. PMID:27516594^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Whicher JR, MacKinnon R. Structure of the voltage-gated K(+) channel Eag1 reveals an alternative voltage sensing mechanism. Science. 2016 Aug 12;353(6300):664-9. doi: 10.1126/science.aaf8070. PMID:27516594 doi:http://dx.doi.org/10.1126/science.aaf8070