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Nitrate-induced Ca2+signaling is crucial for the primary nitrate response in plants.However,the molecular mechanism underlying the generation of the nitrate-specific calcium signature remains unknown.We report here that a cyclic nucleotide-gated channel(CNGC)protein,CNGC15,and the nitrate transceptor(NRT1.1)constitute a molecular switch that controls calcium influx depending on nitrate levels.The expres-sion of CNGC15 is induced by nitrate,and its protein is localized at the plasma membrane after establish-ment of young seedlings.We found that disruption of CNGC15 results in the loss of the nitrate-induced Ca2+signature(primary nitrate response)and retards root growth,reminiscent of the phenotype observed in the nrt1.1 mutant.We further showed that CNGC15 is an active Ca2+-permeable channel that physically inter-acts with the NRT1.1 protein in the plasma membrane.Importantly,we discovered that CNGC15-NRT1.1 interaction silences the channel activity of the heterocomplex,which dissociates upon a rise in nitrate levels,leading to reactivation of the CNGC15 channel.The dynamic interactions between CNGC15 and NRT1.1 therefore control the channel activity and Ca2+influx in a nitrate-dependent manner.Our study re-veals a new nutrient-sensing mechanism that utilizes a nutrient transceptor-channel complex assembly to couple nutrient status to a specific Ca2+signature.