Biomedical Engineering Reference
In-Depth Information
Fig. 1 Schematic diagram of
hERG
K
+
channel. Structure of the different regions of
hERG
K
+
channel has been shown with their different subunits, which are involved in QT prolongation
sequences. The four S1-S4 segments, each containing four positively charged
arginine residues in the S4 helix, act as voltage sensor domains and “gate” the
pore by “pulling” on the S4-S5 linker [
1
,
2
]. All the 40 genes that encode the K
v
channels in the human genome have been cloned and their biophysical properties
have been characterized. However, it often remains a challenge to determine
precisely which channel underlies a K
+
current in a native tissue. This is because,
within subfamilies, such as the K
v1
and K
v7
families,
the
-subunits can
a
