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How metazoan mechanotransduction channels sense mechanical stimuli is not well understood. NOMPC channel in the transient receptor potential (TRP) family, a mechanotransduction channel for Drosophila touch sensation and hearing, contains 29 Ankyrin repeats (ARs) that associate with microtubules. These ARs have been postulated to act as a tether that conveys force to the channel. Here, we report that these N-terminal ARs form a cytoplasmic domain essential for NOMPC mechanogating in vitro, mechanosensitivity of touch receptor neurons in vivo, and touch-induced behaviors of Drosophila larvae. Duplicating the ARs elongates the filaments that tether NOMPC to microtubules in mechanosensory neurons. Moreover, microtubule association is required for NOMPC mechanogating. Importantly, transferring the NOMPC ARs to mechano-insensitive voltage-gated potassium channels confers mechanosensitivity to the chimeric channels. These experiments strongly support a tether mechanism of mechanogating for the NOMPC channel, providing insights regarding the basis of mechanosensitivity of mechanotransduction channels.

Ionotropic Receptors (IRs) are a large subfamily of variant ionotropic glutamate receptors present across Protostomia. While these receptors are most extensively studied for their roles in chemosensory detection, recent work has implicated two family members, IR21a and IR25a, in thermosensation in Drosophila. Here we characterize one of the most evolutionarily deeply conserved receptors, IR93a, and show that it is co-expressed and functions with IR21a and IR25a to mediate physiological and behavioral responses to cool temperatures. IR93a is also co-expressed with IR25a and a distinct receptor, IR40a, in a discrete population of sensory neurons in the sacculus, a multi-chambered pocket within the antenna. We demonstrate that this combination of receptors is required for neuronal responses to dry air and behavioral discrimination of humidity differences. Our results identify IR93a as a common component of molecularly and cellularly distinct IR pathways important for thermosensation and hygrosensation in insects. DOI: http://dx.doi.org/10.7554/eLife.17879.001

Ionotropic Receptors (IRs) are a large subfamily of variant ionotropic glutamate receptors present across Protostomia. While these receptors are most extensively studied for their roles in chemosensory detection in insects, recent work has implicated two family members, IR21a and IR25a, in thermosensation in Drosophila. Here we characterize one of the most deeply conserved receptors, IR93a, and show that it is co-expressed and functions with IR21a and IR25a to mediate physiological and behavioral responses to cool temperatures. IR93a is also co-expressed with IR25a and a distinct receptor, IR40a, in a discrete population of sensory neurons in the sacculus, a multi-chambered pocket within the antenna. We demonstrate that this combination of receptors is important for neuronal responses to dry air and behavioral discrimination of humidity differences. Our results identify IR93a as a common component of molecularly and cellularly distinct IR pathways underlying thermosensation and hygrosensation in insects.

Background Recreational usage and attitudes toward psilocybin-containing hallucinogenic mushrooms among college students are seldom explored. Methods We surveyed 882 randomly selected undergraduates at Skidmore College in upstate New York and quantified whether participants had ever used psilocybin mushrooms, their attitudes toward the drug, and polydrug use. Results There were 409 responses and 29.5% of the sample reported psilocybin use. Among users, the mean number of times they reported using mushrooms was 3.4 (mode = 1). The top factors cited that influenced their decisions to try hallucinogenic mushrooms for the first time were ‘curiosity’, ‘to achieve a mystical experience’, and ‘introspection’. Users and non-users had significantly different perceptions of mushrooms: non-users were more likely to say that hallucinogenic mushrooms were addictive and had the potential for abuse than users. Users did not believe that psilocybin negatively impacts their academics, mental health, or physical health, while non-users did. Both users and non-users of psilocybin reported high life-time use of alcohol (97% vs 96%, respectively), marijuana (98% vs 73%, respectively) and tobacco (82% vs 54%, respectively). Psilocybin users were significantly more likely to use other drugs such as cocaine, ecstasy, opiates, non-prescribed prescription drugs, opiates, and lysergic acid diethylamide (LSD) than non-users of psilocybin. Conclusion This study uncovers important insights into hallucinogenic mushroom use by college students.