Invertebrate Neuroscience

, Volume 2, Issue 4, pp 283–291 | Cite as

Novel embryonic regulation of Ca2+-activated K+ channel expression inDrosophila

  • Tarita Thomas
  • Bin Wang
  • Robert Brenner
  • Nigel S. Atkinson


Theslowpoke gene ofDrosophila melanogaster encodes a Ca2+-activated K+ channel that is expressed in neurons, muscles, tracheal cells and the middle midgut. The entire transcriptional control region ofslowpoke is contained in 11 kb of genomic DNA. Previous work has identified four different tissue-specific promoters (Promoters C1, C1b, C1c and C2) and sequences that regulate their activity. Here we describe and contrast the regulation of neuronal and muscle expression during embryogenesis with its regulation during larval and adult stages. Embryonic regulation is fundamentally different. The embryo uses Promoter C1 and a previously undescribed promoter, called Promoter Ce, to drive neuronal expression. The expression patterns of these promoters are distinct. Muscle expression arises from Promoter C2 as in other developmental stages. A downstream intronic region has been shown to contain control elements that modulate promoter activity differently in embryos, larvae and adults. Embryonic CNS expression is not dependent on the intron, however; its deletion has substantial effects on neuronal expression in larvae and adults. In embryonic muscle, removal of the intron eliminates muscle expression even though this deletion does not reduce larval muscle expression.

Key words

Drosophila potassium channel slowpoke calcium-activated gene regulation embryo 


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Copyright information

© Sheffield Academic Press 1997

Authors and Affiliations

  • Tarita Thomas
    • 1
  • Bin Wang
    • 1
  • Robert Brenner
    • 1
  • Nigel S. Atkinson
    • 1
  1. 1.Department of ZoologyThe University of Texas at AustinAustinUSA

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