Molecular structure and expression of shaker type potassium channels in glial cells of trout CNS

Two shaker-related potassium channel transcripts (tsha1, tsha2) were identified in glial cells ok trout central nervous system (CNS) by polymerase chain reaction (PCR)-cloning and sequencing. While tsha1 was highly similar to the mammalian Kv1.2 subtype or potassium channels, tsha2 did not show a preferential sequence homology with a particular subtype of shaker but exhibited uniform similarity with mammalian Kv1.1, Kv1.2,a, acid Kv1.3,, respectively. transcripts for the shaw and shal subfamilies of voltage-gated potassium channels were detected in whole brain tissue only but not in freshly dissociated glial cells, Using mRNA extracted from different glial cell types in combination with sequence sg?specific PCR primers, tsha1 was found restricted to oligodendrocytes and their progenitor cells, while tsha2 was common to astrocytes, as well. (C) 1998 Wiley-Liss, Inc.