초파리 돌연변이인 pyrexia의 특성 분석 = Characterization of Drosophila pyrexia mutants

다국어 초록 (Multilingual Abstract)

Recent advance in research on ion channels in sensory neurons reveals molecular mechanism underlying how various types of stimuli can be transduced to neural signals transmitted to the brain for pain perception. When these channels are activated, inward currents or outward currents are generated, which will lead to depolarization or hyperpolarization of the membrane causing increased or decreased excitability of sensory neurons. TRPV1 is a ligand-gated cation channel with preference for divalent cations, especially Ca2+ and selectively express in a subpopulation of nociceptive, primary sensory neurons. We generated PainFly, missexpressed hVR1 by MD-Gal4. The threshold probe temperature for eliciting this behavior of PainFly is 30℃. Pyrexia is to protect flies from high-temperature stress. It is ubiquitously expressed along the dendrites of a subset of peripheral nervous system neurons and is more permeable to K+ than to Na+. So we compared temperature preference, heat probe test and thermotolerance in PainFly and Pyrexia mutant and missexpressed fly larvae. About 50% of control, MD>UAS-GFP display nociceptive behavior in 40℃. But about 50% of PainFly display nociceptive behavior in 32℃. And homomeric misexpressions and mutants of pyx had a similar reaction percentage to that of MD>UAS-GFP. But heteromeric misexpression of Pyx display lower noxious behavior than control. PainFly larvae were a higher thermotolerance than that of MD>UAS-GFP in 39℃, but were a similar thermotolerance to that of MD>UAS-GFP in 42℃. pyxDf9 larvae also were a higher thermotolerance than that of MD>UAS-GFP in 39℃, but were a similar thermotolerance to that of MD>UAS-GFP in 42℃. pyx3 and pyxDf4 larvae were a higher thermotolerance than that of MD>UAS-GFP in 39 and 42℃. And misexpressions of Pyx were a similar thermotolerance to that of MD>UAS-GFP in 39 and 42℃. From these findings, we found that PainFly larvae are sensitive to normal heat, pyx mutant larvae are sensitive to high-temperature stress and misexpressions larvae of Pyx don't protect from high-temperature stress.

목차 (Table of Contents)

• Introduction 3
• Materials and Methods 7
• - Drosophila melanogaster stock 7
• - Heat probe test 7
• - Thermotexis assay 7
• - Temperature preference behavioral assay 8
• - Thermotolerance assay 8
• Results 10
• Discussion 20