Multiple products of the Drosophila Shaker gene may contribute to potassium channel diversity.
K+ channels are known through electrophysiology and pharmacology to be an exceptionally diverse group of channels. Molecular studies of the Shaker (Sh) locus in Drosophila have provided the first glimpse of K+ channel structure. The sequences of several Sh cDNA clones have been reported; none are identical. We have isolated and examined 18 additional Sh cDNAs in an attempt to understand the origin, extent, and significance of the variability. The diversity is extensive: we have already identified cDNAs representing at least nine distinct types, and Sh could potentially encode 24 or more products. This diversity, however, fits a simple pattern in which variable 3' and 5' ends are spliced onto a central constant region to yield different cDNA types. These different Sh cDNAs encode proteins with distinct structural features.
Kamb
A
A
Division of Biology, California Institute of Technology, Pasadena 91125.
Tseng-Crank
J
J
Tanouye
M A
MA
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004330:Drosophila / Q000235:genetics*; D005796:Genes; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D015221:Potassium Channels / Q000378:metabolism*; D011487:Protein Conformation; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D008565:Membrane Proteins; D015221:Potassium Channels; D004247:DNA