Hyperpolarization-activated ion channel exhibiting weak selectivity for potassium over sodium ions. Contributes to the native pacemaker currents in heart (If) and in neurons (Ih). Produces a large instantaneous current. Activated by cAMP. Modulated by intracellular chloride ions and pH; acidic pH shifts the activation to more negative voltages.
Specificity
Natural and recombinant Mouse Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2
The potassium channel is probably composed of a homo- or heterotetrameric complex of pore-forming subunits. Heteromultimer with HCN1. Interacts with KCNE2.