Figure 1.

Overview of Kv channel structure. (A) A top down view of the Kv1.2 open state channel tetramer (PDB: 2A79) with the voltage-sensing domains (S1–S4) in color. The charge carrying S4 segment of the voltage sensor domain is highlighted magenta and the pore domain S5–S6 segments are gray. (B) Side view of two pore forming subunits of the Kv1.2 illustrating the selectivity filter containing two K⁺ ions of a possible four in positions 2 and 4 shown in blue and a K⁺ ion residing in the intracellular cavity in magenta.