Figure 3

Schematic topology and partial protein sequence of KCNQ4. (A) Schematic topology represents six transmembrane helices (S1–S6) and the K⁺-selective channel pore region (S5, PH, P-loop, and S6) of KCNQ4. (B) Sequences of the orthologous KCNQ4 pore region are aligned. Positions highlighted in green indicate the amino acid is the same as in human KCNQ4. The position of Tyr270 is indicated by an arrow. The positions of S5, PH, S6 (wavy lines) and the P-loop (straight line) are shown below the sequences. (C) Alignment of the KCNQ4 pore-region sequence with those of Kv channels deposited in PDB. Positions highlighted in green indicate the amino acid is the same as in human KCNQ4. The sequence of human KCNQ4 is indicated at the top of both alignments.