HCN3 Proteins and Enzymes

FUNCTION: Putative hyperpolarization-activated ion channel exhibiting weak selectivity for potassium over sodium ions. SUBUNIT: The potassium channel is probably composed of a homo- or heterotetrameric complex of pore-forming subunits. SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein. DOMAIN: The segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position.