Identification of Two Nervous System-Specific Members of the<i>erg</i>Potassium Channel Gene Family

Abstract

Two new potassium channel genes, erg 2 and erg 3, that are expressed in the nervous system of the rat were identified. These two genes form a small gene family with the previously described erg 1 (HERG) gene. The erg 2 and erg 3 genes are expressed exclusively in the nervous system, in marked contrast to erg 1, which is expressed in both neural and non-neural tissues. All three genes are expressed in peripheral sympathetic ganglia. The erg 3 channel produces a current that has a large transient component at positive potentials, whereas the other two channels are slowly activating delayed rectifiers. Expression of the erg 1 gene in the sympathetic nervous system has potential implications for the etiology of the LQT2 form of the human genetic disease long QT syndrome.