Behavioral and Electrophysiological
Analysis of Ca-activated K-channel
Transgenes in Drosophilaa
NIGEL S. ATKINSON,b
ROBERT BRENNER, RUDI A. BOHM,
JOYCE Y. YU, AND JENNETTE L. WILBUR
Department of Zoology and The Institute of Molecular Biology, The
University of Texas at Austin, Austin, Texas 78712-1064, USA
ABSTRACT: The slowpoke gene of Drosophila melanogaster encodes a Ca-activated K
channel. This gene is expressed in neurons, muscles, tracheal cells, and the copper
and iron cells of the midgut. The gene produces a large number of alternative prod-
ucts using tissue-specific transcriptional promoters and alternative mRNA splicing.
We have described in great depth how transcription is regulated and are now cata-
loging the tissue-specificity of different splice variants. It is believed that the diversity
of products serves to tailor channel attributes to the needs of specific tissues.
Electrophysiological and behavioral assays indicate that at least some of these prod-
ucts produce channels with distinct properties.
The range of electrical properties that a cell can produce is ultimately limited by the
suite of ion channel genes that it expresses. For the cell this is not a simple decision.