title: Targeting HSP70 to motoneurons protects locomotor activity from hyperthermia in Drosophila.
abstract: Heat shock preconditioning can enhance locomotor and synaptic performance during subsequent hyperthermia. The molecular basis underlying this neural phenotypic modification is largely unknown. Here we report that directing the expression of the 70 kDa heat shock protein (HSP70) to motoneurons protected larval locomotor activity of Drosophila. Tissue-specific expression showed that motoneurons were critical for developing HSP70-mediated thermoprotection of locomotor activity, whereas peripheral sensory neurons, dopaminergic neurons, serotonergic neurons, and muscle cells alone were insufficient. Targeting HSP70 to motoneurons caused structural plasticity of axonal terminals associated with increased transmitter release at neuromuscular junctions at high temperature. The thermoprotection induced by motoneuronal expression of HSP70 mimicked the protective effect of a prior heat shock (36 degrees C, 1 h; 25 degrees C, 1 h) but the effects of heat shock and motoneuronal expression of HSP70 were not additive. In the absence of heat shock pretreatment, ubiquitously expressed transgenic HSP70 activated the transcription of endogenous hsp70 genes. These results demonstrate that motoneurons were critical for HSP70-mediated thermoprotection, and that transgenic HSP70 activated the transcription of endogenous hsp70 in motoneurons with the result that a mix of transgenic and endogenous HSP70 conferred thermoprotection in Drosophila larva.
authors: Department of Biology, Queen's University, Kingston, Ontario K7L 3N6 Canada.
authors: Chengfeng
authors: C
authors: Xiao
authors: Viara
authors: V
authors: Mileva-Seitz
authors: Laurent
authors: L
authors: Seroude
authors: R Meldrum
authors: RM
authors: Robertson
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001522:Behavior, Animal; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D005334:Fever / Q000235:genetics / Q000503:physiopathology*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000502:physiology*; D018869:Heat-Shock Response / Q000502:physiology; D007814:Larva; D009043:Motor Activity / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology*; D032342:Muscle Cells / Q000502:physiology; D009469:Neuromuscular Junction / Q000503:physiopathology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
chemical_list: D029721:Drosophila Proteins; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger