Suehiro Yuji
   Department   Research Institutes and Facilities, Research Institutes and Facilities
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title OFF-responses of interneurons optimize avoidance behaviors depending on stimulus strength via electrical synapses.
Journal Formal name：PLoS genetics
Abbreviation：PLoS Genet
ISSN code：(1553-7404)1553-7390(Linking)
Domestic / ForeginForegin
Volume, Issue, Page 14(6),pp.e1007477
Author and coauthor Hori Sayaka, Oda Shigekazu, Suehiro Yuji, Iino Yuichi, Mitani Shohei
Publication date 2018/06
Summary 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