Sequence alignment of S1–S4 voltage-sensing domains. (A) Sequence alignment from the output MSA of Palovcak et al. (2014), including Shaker Kv (UniProt accession no. P08510), Kv1.2/2.1 paddle chimera (Protein Data Bank accession no. 2R9R_B), rat Kv2.1 (UniProt accession no. P15387), rat Kv1.2 (UniProt accession no. P63142), human Kv11.1 (UniProt accession no. Q12809), KvAP (UniProt accession no. Q9YDF8), human Hv1 (UniProt accession no. Q96D96), Ciona VSP (UniProt accession no. Q4W8A1), and NavAb (UniProt accession no. A8EVM5). Conserved positions are colored as follows: polar, green; hydrophobic, black; acidic, red; and basic, blue. Positions highlighted in yellow have not been extensively studied previously but are identified as highly conserved by Palovcak et al. (2014). Helices are positioned according to the structure of the Kv1.2/2.1 paddle chimera (2R9R; Long et al., 2007). (B) Alternative alignment of S1 that takes into consideration the longer S1 helix in Kv channels (Long et al., 2007) compared with Nav channels (Payandeh et al., 2011). In this alignment, positions 11 and 14 in NavAb are equally or more highly conserved than in A, and position 15 becomes highly conserved.