Localization of a highly conserved human potassium channel gene (NGK2-KV4; KCNC1) to chromosome 11p15.

Several genes (the Shaker or Sh gene family) encoding components of voltage-gated K+ channels have been identified in various species. Based on sequence similarities Sh genes are classified into four groups or subfamilies. Mammalian genes of each one of these subfamilies also show high levels of sequence similarity to one of four related Drosophila genes: Shaker, Shab, Shaw, and Shal. Here we report the isolation of human cDNAs for a Shaw-related product (NGK2, KV3.1a) previously identified in rat and mice. A comparison of the nucleotide and deduced amino acid sequence of NGK2 in rodents and humans shows that this product is highly conserved in mammals; the human NGK2 protein shows over 99% amino acid sequence identity to its rodent homologue. The gene (NGK2-KV4; KCNC1) encoding NGK2 was mapped to human chromosome 11p15 by fluorescence in situ hybridization with the human NGK2 cDNAs.