Probable ion channel (PubMed:27478019, PubMed:30853433, PubMed:31184585, PubMed:32649914). Component of mechanosensitive neurons that participates in proprioception, sensing food texture, and directing egg-laying site selection (oviposition) (PubMed:27478019, PubMed:27298354, PubMed:30853433, PubMed:31184585, PubMed:32649914). Component of multi-dendritic neurons of the labellum (md-L) where it is required for sensing the hardness and viscosity of their food, enabling them to behaviorally discriminate their preferred softness and smoothness from harder and stickier food options (PubMed:27478019). Required as part of oviposition site selection process to relay mechanosensory and chemosensory information on the hardness and sweetness of potential egg-laying substrates, thus ensuring females select the most optimal site for their eggs survival (PubMed:31184585, PubMed:32649914). Females determine the softest substrate for their eggs first by making a coarse evaluation of substrate hardness using mechanosensitive channels nan and Piezo in the leg tarsal bristles, followed by a much finer assessment using nan, iav and Tmc mechanosensitive channels on the labellum (PubMed:31184585, PubMed:32649914). This protein is required to sense subtle differences in substrate stiffness (between 0.25% and 0.3% agarose), likely acting in the md-L neurons (PubMed:32649914). Also required in neurons on the labellum, including the md-Ls, and possibly in the brain, to inhibit discrimination of egg-laying substrates of different hardness if the substrate contains sucrose (PubMed:32649914). During oviposition evaluation, activation of sweet neurons by sucrose enhances the activity of the Tmc neurons resulting in females losing their softness preference in favor of egg-laying sites that contain sucrose (PubMed:32649914). Acts in the larvae peripheral sensory neurons, to contribute to proprioception and sensory feedback for normal forward crawling behavior (PubMed:27298354, PubMed:30853433). Required for the normal activity of the proprioceptive sensory dendrites, ddaE which show preferential responses to forward locomotion, and ddaD which show preferential responses to backward locomotion (PubMed:30853433). Expressed in multi-dendritic neurons of the labellum (md-L), which extend elaborate dendritic arbors innervating the bases of taste hairs (at protein level) (PubMed:27478019). In larvae, expressed in class I and class II dendritic arborization (da) neurons and bipolar dendrite (bd) neurons (at protein level) (PubMed:27298354). In adults, expressed in various sensory neurons including those in the mouth parts, olfactory neurons in the antenna, wing bristle neurons, haltere neurons, arista neurons, and many other sensory neurons, including a subset of chordotonal (Cho) neurons (PubMed:27478019, PubMed:27298354). Expressed in md-L axon terminals, including those that project into the subesophageal zone (SEZ) (PubMed:27478019, PubMed:31184585). Also expressed in a small number of local neurons in the adult ventral nerve cord (VNC), and projections extending from a few neurons in the legs or wing hinges (PubMed:27478019). In the adult mouth, expressed in a few multi-dendritic neurons of the ventral cibarial sensory organ (VCSO); the multiple elaborate dendritic branches form a brush-like structure that faces the luminal side of the food-passing tunnel (PubMed:27478019). Also expressed in the oviduct and uterus of adult females (PubMed:32649914). Viable and appear morphologically normal (PubMed:27478019). Adults display a significant reduction in the electrophysiological responses of multi-dendritic neurons of the labellum (md-L) to mechanical stimuli (PubMed:27478019). Adults are unable to discriminate between the preferred softness (1% agarose) or smoothness (sucrose solution only) from harder or stickier food options (PubMed:27478019). Adult females display a reduced ability to discriminate between small differences in egg-laying substrate stiffness (PubMed:32649914). Larvae display abnormal locomotion behaviors that likely result from the loss of proprioceptive feedback (PubMed:27298354, PubMed:30853433). Displays reduced sensitivity to movement direction due to decreased activity of the dorsal proprioceptors neurons ddaD, which are activated during backward movement, and ddaE neurons which are activated during forward movement (PubMed:30853433). As a consequence, larvae crawling speed is reduced due to increased head curl behavior and increased backward locomotion (PubMed:27298354). No obvious defects in larvae dendrite morphology of class I da neurons or axon targeting of neurons in the ventral nerve cord (PubMed:27298354). Adults display a normal avoidance of bitter tastes such as quinine, denatonium, strychnine and berberine, and L4 and S6 sensilla display normal electrophysiological responses to salt, sucrose and caffeine (PubMed:27478019). Belongs to the TMC family.