Kir3.4 is a member of the G-protein regulated inward-rectifier K+ (GIRK) channel subfamily which is part of an inward-rectifier K+ channel superfamily. The GIRK subfamily comprises four members in mammals (Kir3.1- Kir3.4) that present the common topology of the inward-rectifier superfamily: two transmembrane domains flanking a highly conserved pore region with the N and C-terminus located intracellularly.
Kir3.4 and the other Kir3 family subunits can be activated by neurotransmitters and other factors via the activation of G-protein coupled receptors. Binding of the corresponding ligand to the G-protein receptor induces the dissociation of G
