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The Ras–MAP kinase signaling pathway plays important roles for the olfactory reception in olfactory neurons inCaenorhabditis elegans. However, given the absence of phosphorylation targets of MAPK in the olfactory neurons, the mechanism by which this pathway regulates olfactory function is unknown. Here, we used proteomic screening to identify the mitochondrial voltage-dependent anion channel VDAC-1 as a candidate target molecule of MAPK in the olfactory system ofC. elegans. We found that Amphid Wing “C” (AWC) olfactory neuron-specific knockdown ofvdac-1caused severe defects in chemotaxis toward AWC-sensed odorants. We generated a newvdac-1mutant using the CRISPR-Cas9 system, with this mutant also showing decreased chemotaxis toward odorants. This defect was rescued by AWC-specific expression ofvdac-1, indicating that functions of VDAC-1 in AWC neurons are essential for normal olfactory reception inC. elegans. We observed that AWC-specific RNAi ofvdac-1reduced AWC calcium responses to odorant stimuli and caused a decrease in the quantity of mitochondria in the sensory cilia. Behavioral abnormalities invdac-1knockdown animals might therefore be due to reduction of AWC response, which might be caused by loss of mitochondria in the cilia. Here, we showed that the function of VDAC-1 is regulated by phosphorylation and identified Thr175 as the potential phosphorylation site of MAP kinase.vdac-1 is important for calcium responses of the AWC olfactory neurons. Calcium imaging showed large reduction in the response to an odorant in vdac-1 mutants.