Potassium Channel Subfamily K, Member 7 (KCNK7)

Members of the tandem pore domain potassium (K2P) channel family, such as TWIK1 and TREK, contain 4 transmembrane domains and 2 pore-forming (P) domains. The predicted 307-amino acid KCNK7A form is the longest; KCNK7B and KCNK7C have truncated cytoplasmic C termini. Sequence analysis revealed that the KCNK7 protein contains 4 potential transmembrane segments and 2 P domains. The P2 domain contains a very unconventional GLE motif instead of the GLG found in TWIK1 and KCNK6 or the GFG found in other K2P channels. The core region spanning the 4 transmembrane domains of KCNK7A shares 80% and 42% protein sequence identity with those of Kcnk6 and TWIK1, respectively. As with Kcnk6, none of the KCNK7 protein forms were able to generate channel activity when expressed in mammalian cells.