inward rectifier K+ channel 18; K+ channel, inwardly rectifying subfamily J member 18; Inward rectifier K+ channel Kir2.6 (KCNJ18)

Function: - inward-rectifier K⁺ channels are characterized by a greater tendency to allow K⁺ to flow into the cell rather than out of it - their voltage dependence is regulated by the concentration of extracellular K⁺; as external K⁺ is raised, the voltage range of the channel opening shifts to more positive voltages - the inward rectification is mainly due to the blockage of outward current by internal Mg⁺² - probably phosphorylated by PKC; decreases single-channel open probability Structure: - belongs to the inward rectifier-type K⁺ channel (TC 1.A.2.1) family, KCNJ12 subfamily Compartment: - cell membrane; multi-pass membrane protein (probable) Expression: - specifically expressed in skeletal muscle - up-regulated by triiodothyronine Pathology: - defects in KCNJ18 are a cause of susceptibility to thyrotoxic hypokalemic periodic paralysis

Properties

SIZE: entity length = 433 aa MW = 49 kD COMPARTMENT: plasma membrane MOTIF: cytoplasmic domain {1-84} transmembrane domain {85-105} exoplasmic loop {106-156} transmembrane domain {157-177} cytoplasmic domain {178-433} ION-PERMEABILITY: K+

Database Correlations

OMIM correlations UniProt B7U540 PFAM correlations

References

UniProt :accession B7U540