ミタニ シヨウヘイ   MITANI Shohei
  三谷 昌平
   所属   医学部 医学科
   職種   教授・講座主任
論文種別 原著
言語種別 英語
査読の有無 査読あり
表題 OFF-responses of interneurons optimize avoidance behaviors depending on stimulus strength via electrical synapses.
掲載誌名 正式名:PLoS genetics
略  称:PLoS Genet
ISSNコード:(1553-7404)1553-7390(Linking)
掲載区分国外
巻・号・頁 14(6),e1007477頁
著者・共著者 Hori Sayaka, Oda Shigekazu, Suehiro Yuji, Iino Yuichi, Mitani Shohei
発行年月 2018/06
概要 Optimization of the types and timing of avoidance behaviors depending on the intensity of a noxious stimulus is essential for survival; however, processing in the central nervous system and its developmental basis are largely unknown. Here, we report that Caenorhabditis elegans preferentially selects one of three different types of avoidance behaviors depending on the strength of the noxious stimulus. We screened 210 neuronal transcription factors using a combination of optogenetics and RNA interference methods and identified 19 candidates required for avoidance behaviors. One candidate, gene lin-32 (abnormal cell LINeage 32), which encodes an atonal homolog, is required for the neural fate determination of AIB interneurons and functions by regulating the expression of electrical and chemical synapse genes, namely, inx-1 (innexin 1) and AMPA-type ionotropic glutamate receptor glr-1. When examined by Ca imaging, AIB showed an OFF calcium increase to the noxious stimulus. The OFF calcium increase was provoked only by strong stimulation, suggesting a role for optimization of the avoidance behavior. However, lin-32 mutants showed an impaired AIB OFF calcium increase, concomitant with a reduced occurrence of the dynamic avoidance behavior called the "omega turn". The AIB neural responses may be transferred to downstream inter/motor neurons projecting to the neck muscles via electrical synapses comprising inx-1. Finally, we found a correlation between powerful contractions of the neck muscles and omega turns. Thus, the central regulation of the magnitude and timing of activation of the AIB interneurons optimizes the probability of omega turn depending on the stimulus context.
DOI 10.1371/journal.pgen.1007477
PMID 29939997