Spatial and temporal control of gene expression in Drosophila using the inducible GeneSwitch GAL4 system. I. Screen for larval nervous system drivers

Genetics. 2008 Jan;178(1):215-34. doi: 10.1534/genetics.107.081968.


There is a critical need for genetic methods for the inducible expression of transgenes in specific cells during development. A promising approach for this is the GeneSwitch GAL4 system of Drosophila. With GeneSwitch GAL4 the expression of upstream activating sequence (UAS) effector lines is controlled by a chimeric GAL4 protein that becomes active in the presence of the steroid RU486 (mifepristone). To improve the utility of this expression system, we performed a large-scale enhancer-trap screen for insertions that yielded nervous system expression. A total of 204 GeneSwitch GAL4 lines with various larval expression patterns in neurons, glia, and/or muscle fibers were identified for chromosomes I-III. All of the retained lines show increased activity when induced with RU486. Many of the lines reveal novel patterns of sensory neurons, interneurons, and glia. There were some tissue-specific differences in background expression, with muscles and glia being more likely to show activity in the absence of the inducing agent. However, >90% of the neuron-specific driver lines showed little or no background activity, making them particularly useful for inducible expression studies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / drug effects
  • Brain / metabolism
  • DNA-Binding Proteins
  • Drosophila melanogaster / cytology
  • Drosophila melanogaster / drug effects
  • Drosophila melanogaster / genetics*
  • Enhancer Elements, Genetic / genetics
  • Gene Expression Regulation* / drug effects
  • Genes, Switch*
  • Larva / drug effects
  • Larva / genetics
  • Mifepristone / pharmacology
  • Motor Neurons / cytology
  • Motor Neurons / drug effects
  • Motor Neurons / metabolism
  • Muscles / cytology
  • Muscles / drug effects
  • Muscles / metabolism
  • Mutagenesis, Insertional
  • Nervous System / drug effects
  • Nervous System / metabolism*
  • Neuroglia / cytology
  • Neuroglia / drug effects
  • Neuroglia / metabolism
  • Neuromuscular Junction / cytology
  • Neuromuscular Junction / drug effects
  • Neuromuscular Junction / genetics
  • Neurons, Afferent / cytology
  • Neurons, Afferent / drug effects
  • Neurons, Afferent / metabolism
  • Phenotype
  • Saccharomyces cerevisiae Proteins / genetics*
  • Transcription Factors / genetics*
  • Transgenes


  • DNA-Binding Proteins
  • GAL4 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • Mifepristone