RRC ID 46369
著者 Husson SJ, Costa WS, Wabnig S, Stirman JN, Watson JD, Spencer WC, Akerboom J, Looger LL, Treinin M, Miller DM 3rd, Lu H, Gottschalk A.
タイトル Optogenetic analysis of a nociceptor neuron and network reveals ion channels acting downstream of primary sensors.
ジャーナル Curr Biol
Abstract BACKGROUND:Nociception generally evokes rapid withdrawal behavior in order to protect the tissue from harmful insults. Most nociceptive neurons responding to mechanical insults display highly branched dendrites, an anatomy shared by Caenorhabditis elegans FLP and PVD neurons, which mediate harsh touch responses. Although several primary molecular nociceptive sensors have been characterized, less is known about modulation and amplification of noxious signals within nociceptor neurons. First, we analyzed the FLP/PVD network by optogenetics and studied integration of signals from these cells in downstream interneurons. Second, we investigated which genes modulate PVD function, based on prior single-neuron mRNA profiling of PVD.
RESULTS:Selectively photoactivating PVD, FLP, and downstream interneurons via Channelrhodopsin-2 (ChR2) enabled the functional dissection of this nociceptive network, without interfering signals by other mechanoreceptors. Forward or reverse escape behaviors were determined by PVD and FLP, via integration by command interneurons. To identify mediators of PVD function, acting downstream of primary nocisensor molecules, we knocked down PVD-specific transcripts by RNAi and quantified light-evoked PVD-dependent behavior. Cell-specific disruption of synaptobrevin or voltage-gated Ca(2+) channels (VGCCs) showed that PVD signals chemically to command interneurons. Knocking down the DEG/ENaC channel ASIC-1 and the TRPM channel GTL-1 indicated that ASIC-1 may extend PVD's dynamic range and that GTL-1 may amplify its signals. These channels act cell autonomously in PVD, downstream of primary mechanosensory molecules.
CONCLUSIONS:Our work implicates TRPM channels in modifying excitability of and DEG/ENaCs in potentiating signal output from a mechano-nociceptor neuron. ASIC-1 and GTL-1 homologs, if functionally conserved, may denote valid targets for novel analgesics.
巻・号 22(9)
ページ 743-52
公開日 2012-5-8
DOI 10.1016/j.cub.2012.02.066
PII S0960-9822(12)00253-9
PMID 22483941
PMC PMC3350619
MeSH Ion Channels / metabolism* Neurons / cytology* Neurons / metabolism
IF 9.601
引用数 42
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY CELL BIOLOGY
リソース情報
線虫 tm1552