title: Contrasting influences of Drosophila white/mini-white on ethanol sensitivity in two different behavioral assays.
abstract: BACKGROUND
  The fruit fly Drosophila melanogaster has been used extensively to investigate genetic mechanisms of ethanol (EtOH)-related behaviors. Many past studies in flies, including studies from our laboratory, have manipulated gene expression using transposons carrying the genetic-phenotypic marker mini-white(mini-w), a derivative of the endogenous gene white(w). Whether the mini-w transgenic marker or the endogenous w gene influences behavioral responses to acute EtOH exposure in flies has not been systematically investigated.
  
  
  METHODS
  We manipulated mini-w and w expression via (i) transposons marked with mini-w, (ii) RNAi against mini-w and w, and (iii) a null allele of w. We assessed EtOH sensitivity and tolerance using a previously described eRING assay (based on climbing in the presence of EtOH) and an assay based on EtOH-induced sedation.
  
  
  RESULTS
  In eRING assays, EtOH-induced impairment of climbing correlated inversely with expression of the mini-w marker from a series of transposon insertions. Additionally, flies harboring a null allele of w or flies with RNAi-mediated knockdown of mini-w were significantly more sensitive to EtOH in eRING assays than controls expressing endogenous w or the mini-w marker. In contrast, EtOH sensitivity and rapid tolerance measured in the EtOH sedation assay were not affected by decreased expression of mini-w or endogenous w in flies.
  
  
  CONCLUSIONS
  EtOH sensitivity measured in the eRING assay is noticeably influenced by w and mini-w, making eRING problematic for studies on EtOH-related behavior in Drosophila using transgenes marked with mini-w. In contrast, the EtOH sensitivity assay described here is a suitable behavioral paradigm for studies on EtOH sensitivity and rapid tolerance in Drosophila including those that use widely available transgenes marked with mini-w.
authors.affiliation: Molecular Biology and Genetics Program, Virginia Commonwealth University, Richmond, Virginia; Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, Virginia.
authors.forename: Robin F
authors.initials: RF
authors.lastname: Chan
authors.forename: Lara
authors.initials: L
authors.lastname: Lewellyn
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: DeLoyht
authors.forename: Kristyn
authors.initials: K
authors.lastname: Sennett
authors.forename: Scarlett
authors.initials: S
authors.lastname: Coffman
authors.forename: Matthew
authors.initials: M
authors.lastname: Hewitt
authors.forename: Jill C
authors.initials: JC
authors.lastname: Bettinger
authors.forename: John M
authors.initials: JM
authors.lastname: Warrick
authors.forename: Mike
authors.initials: M
authors.lastname: Grotewiel
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001522:Behavior, Animal / Q000187:drug effects; D018118:Chloride Channels / Q000187:drug effects; D004251:DNA Transposable Elements / Q000235:genetics; D004331:Drosophila melanogaster / Q000187:drug effects / Q000235:genetics; D004361:Drug Tolerance / Q000235:genetics; D000431:Ethanol / Q000494:pharmacology*
chemical_list: D018118:Chloride Channels; D004251:DNA Transposable Elements; D000431:Ethanol
keywords: Alcohol; Behavior; Fruit Flies; Genetics; Intoxication; Sedation