title: A congenital heart defect in Drosophila caused by an action-potential mutation.
abstract: The mutation no action potential (nap) induces arrhythmia in the heartbeat of Drosophila melanogaster larvae at temperatures above 20 degrees C; heartbeat becomes normally rhythmic again after a shift back to 20 degrees C. For this phenotype, napa is almost completely recessive to the wild type, napa also reduces the temperature-sensitivity of heart rate over a wide range of temperature, for this phenotype, napa is dominant over the wild type, napa causes reversible paralysis in adults by epistatic effects on the expression of paralyrica, a gene encoding a voltage-dependent sodium channel. However, the paramutation, which induces paralysis in adults at 29 degrees C, has no effect on larval heartbeat at temperatures between 20 degrees and 37.5 degrees C. The period gene, contra earlier reports, has no effect on heartbeat.
authors.affiliation: Department of Zoology, University of Maine, Orono 04469-5751, USA. dowse@maine.maine.edu
authors.forename: H
authors.initials: H
authors.lastname: Dowse
authors.forename: J
authors.initials: J
authors.lastname: Ringo
authors.forename: J
authors.initials: J
authors.lastname: Power
authors.forename: E
authors.initials: E
authors.lastname: Johnson
authors.forename: K
authors.initials: K
authors.lastname: Kinney
authors.forename: L
authors.initials: L
authors.lastname: White
mesh_terms: D000200:Action Potentials / Q000235:genetics; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000235:genetics* / Q000503:physiopathology; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development; D004843:Epistasis, Genetic; D017344:Genes, Insect; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate / Q000235:genetics; D007814:Larva; D009200:Myocardial Contraction / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology; D056950:Period Circadian Proteins; D010641:Phenotype; D015222:Sodium Channels / Q000235:genetics / Q000502:physiology; D013696:Temperature
chemical_list: D029721:Drosophila Proteins; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; D015222:Sodium Channels; C469950:para protein, Drosophila