Developmental expression of voltage-sensitive K⁺ channels in mouse skeletal muscle and C₂C₁₂ cells

The developmental expression of voltage-sensitive K⁺ channels was analyzed by Northern blot in mouse skeletal muscle. Of nine Shaker-like genes studied, eight are expressed in this mammalian muscle. Their expression is differentially regulated during development. The mouse cell line C₂C₁₂ has been used to study expression of voltage-sensitive K⁺ channels during in vitro myotube differentiation. Different voltage-sensitive K⁺ channel messages are also expressed in these cells which display a pattern of expression depending upon the differentiation stage. The message for the very peculiar K⁺ channel or IsK type could only be detected by polymerase chain reaction on skeletal muscle mRNA.