RRC ID 47271
著者 Buhl E, Bradlaugh A, Ogueta M, Chen KF, Stanewsky R, Hodge JJ.
タイトル Quasimodo mediates daily and acute light effects on Drosophila clock neuron excitability.
ジャーナル Proc Natl Acad Sci U S A
Abstract We have characterized a light-input pathway regulating Drosophila clock neuron excitability. The molecular clock drives rhythmic electrical excitability of clock neurons, and we show that the recently discovered light-input factor Quasimodo (Qsm) regulates this variation, presumably via an Na+, K+, Cl- cotransporter (NKCC) and the Shaw K+ channel (dKV3.1). Because of light-dependent degradation of the clock protein Timeless (Tim), constant illumination (LL) leads to a breakdown of molecular and behavioral rhythms. Both overexpression (OX) and knockdown (RNAi) of qsm, NKCC, or Shaw led to robust LL rhythmicity. Whole-cell recordings of the large ventral lateral neurons (l-LNv) showed that altering Qsm levels reduced the daily variation in neuronal activity: qsmOX led to a constitutive less active, night-like state, and qsmRNAi led to a more active, day-like state. Qsm also affected daily changes in K+ currents and the GABA reversal potential, suggesting a role in modifying membrane currents and GABA responses in a daily fashion, potentially modulating light arousal and input to the clock. When directly challenged with blue light, wild-type l-LNvs responded with increased firing at night and no net response during the day, whereas altering Qsm, NKKC, or Shaw levels abolished these day/night differences. Finally, coexpression of ShawOX and NKCCRNAi in a qsm mutant background restored LL-induced behavioral arrhythmicity and wild-type neuronal activity patterns, suggesting that the three genes operate in the same pathway. We propose that Qsm affects both daily and acute light effects in l-LNvs probably acting on Shaw and NKCC.
巻・号 113(47)
ページ 13486-13491
公開日 2016-11-22
DOI 10.1073/pnas.1606547113
PII 1606547113
PMID 27821737
PMC PMC5127355
MeSH Alleles Animals Behavior, Animal Circadian Clocks / radiation effects* Drosophila Proteins / metabolism* Drosophila melanogaster / genetics Drosophila melanogaster / physiology* Drosophila melanogaster / radiation effects* GPI-Linked Proteins / metabolism* Gene Knockdown Techniques Genotype Ion Channel Gating / radiation effects Light* Models, Biological Neurons / physiology* Neurons / radiation effects* Protein Binding / radiation effects gamma-Aminobutyric Acid / metabolism
IF 9.412
引用数 12
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
ショウジョウバエ 2509R-2