BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily G members, KCNG1 and KCNG2
KCNG1, also called voltage-gated potassium channel subunit Kv6.1 or kH2, functions as a regulatory alpha-subunit of voltage-gated potassium channel that can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1. KCNG2, also called cardiac potassium channel subunit or voltage-gated potassium channel subunit Kv6.2, is a new gamma-subunit of voltage-gated potassium channels that can form functional heterodimeric channels with KCNB1, and further modulates channel activity by shifting the threshold and the half-maximal activation to more negative values. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNG1 and KCNG2 are regulatory alpha subunits and do not form homomultimers. They form heteromultimers (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.
Jiyao W et al.(2023). "The conserved domain database in 2023.",