Immobility responses are induced by photoactivation of single glomerular species responsive to fox odour TMT

• Published in: Nature communications 2017-07, Vol.8 (1), p.16011-16011, Article 16011
• Main Authors: Saito, Harumi, Nishizumi, Hirofumi, Suzuki, Satoshi, Matsumoto, Hideyuki, Ieki, Nao, Abe, Takaya, Kiyonari, Hiroshi, Morita, Masahiko, Yokota, Hideo, Hirayama, Nozomi, Yamazaki, Takahiro, Kikusui, Takefumi, Mori, Kensaku, Sakano, Hitoshi
• Format: Article
• Language: English
• Subjects: 38/77; 45/41; 631/378/2624/1703; 631/378/2624/1704; 631/378/2624/2625; 64/60; Animals; Aversion; Aversive Agents - isolation & purification; Aversive Agents - pharmacology; Behavior, Animal - drug effects; Channelrhodopsins - genetics; Channelrhodopsins - metabolism; Cortex; Fear; Fear - drug effects; Fear - psychology; Feces - chemistry; Foxes; Freezing Reaction, Cataleptic - drug effects; Freezing Reaction, Cataleptic - physiology; Gene Expression; Gene Knock-In Techniques; Humanities and Social Sciences; Male; Mice; multidisciplinary; Odorants - analysis; Olfactory bulb; Olfactory Bulb - drug effects; Olfactory Bulb - physiology; Olfactory Perception - physiology; Photic Stimulation; Photoactivation; Receptors; Receptors, Odorant - genetics; Receptors, Odorant - metabolism; Rodents; Science; Science (multidisciplinary); Selectivity; Smell - physiology; Stereotaxic Techniques; Thiazoles - isolation & purification; Thiazoles - pharmacology; Thiazoline
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms16011

Fox odour 2,4,5-trimethyl thiazoline (TMT) is known to activate multiple glomeruli in the mouse olfactory bulb (OB) and elicits strong fear responses. In this study, we screened TMT-reactive odourant receptors and identified Olfr1019 with high ligand reactivity and selectivity, whose glomeruli are located in the posterodorsal OB. In the channelrhodopsin knock-in mice for Olfr1019 , TMT-responsive olfactory-cortical regions were activated by photostimulation, leading to the induction of immobility, but not aversive behaviour. Distribution of photoactivation signals was overlapped with that of TMT-induced signals, but restricted to the narrower regions. In the knockout mice, immobility responses were reduced, but not entirely abolished likely due to the compensatory function of other TMT-responsive glomeruli. Our results demonstrate that the activation of a single glomerular species in the posterodorsal OB is sufficient to elicit immobility responses and that TMT-induced fear may be separated into at least two different components of immobility and aversion. The olfactory bulb is arranged in glomeruli defined by their olfactory receptor expression. The authors identify an olfactory receptor for fox odour, TMT, and show that activation of the glomerulus expressing that receptor in mice leads to immobility, but does not lead to other fear behaviours.