Table 1

Sequence alignment of homologous regions from the S6 of Shaker B, Kv1.5, Kv2.1, HERG1 A, BEAG, ELK1, and KcsA.

ChannelSequenceEquivalent Mutations
Kv1.5 493-IVGSLCAIAGVLTIALPVPVIVSNFNYFY T505-Kv1.5/M651-HERG
SHAKB 457-IVGSLCAIAGVLT I ALP V PVI VSNFNYFY V474-Shaker/F656-HERG
Kv2.1 388-IVGGLCCIAGVLVIALPIPIIVNNFSEFY I405-Kv2.1/F656-HERG
HERG 639-IFSICVMLIGSLMYASIFGNVSAIIQRLY
BEAG 451-IFAVAIMMIGSLLYATIFGNVTTIFQQMY
ELK1 449-IFSICTMLIGALMHALVFGNVTAIIQRMY
KcsA 90 -LVAVVVMVAGITSFGLVTAALATWFVGRE

Amino acids reported to alter affinity for 4-AP, TEAe, and quinidine are indicated in bold (Choi et al., 1993;Shieh et al., 1994; Yeola et al., 1996;Liu et al., 1997; Zhang et al., 1998). Amino acids whose accessibility to intracellular MTS reagents was altered in the open and closed state of the channel are shown in italics and underlined (Liu et al., 1997). GenBank™ accession numbers are rat Kv1.5, M27158; Shaker B, X07132; rat Kv2.1,X16476; HERG, U04270; BEAG, Y13430; rat ELK1, AF061957; and KcsA, (PIR)S60172.