Alternative Splicing of Exons Encoding Portions of the Carboxy-Terminus of K-Cl Cotransporter-4 (KCC4)

Abstract

K-Cl cotransporter-2 (KCC2) is expressed only in neurons of the central nervous system, and its transcript contains two exons (22 and 24) encoding portions of the carboxy-terminus that have long been thought to be unique to this KCC isoform. Here we report that KCC2's closest ortholog, KCC4, exhibits alternative splicing of these two exons. From database analysis and RT-PCR, we identified an alternatively spliced exon encoding 41 amino acids (similar to exon 22 of KCC2) in KCC4 of chicken brain.