Background
Potassium channels represent the most complex class of voltage-gated ion channels from
both functional and structural standpoints. Their diverse functions include regulating
neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial
electrolyte transport, smooth muscle contraction, and cell volume. Four sequence-related
potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila,
and each has been shown to have human homolog(s). This gene encodes a member of the
potassium channel, voltage-gated, shaker-related subfamily. This member contains six
membrane-spanning domains with a shaker-type repeat in the fourth segment. It belongs to
the delayed rectifier class, members of which allow nerve cells to efficiently repolarize
following an action potential. The coding region of this gene is intronless, and the gene is
clustered with genes KCNA3 and KCNA10 on chromosome 1.
