The function of Ensembl gene identifier ENSG00000136636 (KCTD3, potassium channel tetramerization domain containing 3) is as follows. Accessory subunit of potassium/sodium hyperpolarization- activated cyclic nucleotide-gated channel 3 (HCN3) up-regulating its cell-surface expression and current density without affecting its voltage dependence and kinetics. .