Thought to form a receptor-activated non-selective calcium permeant cation channel. Probably is operated by a phosphatidylinositol second messenger system activated by receptor tyrosine kinases or G-protein coupled receptors. Activated by diacylglycerol (DAG) in a membrane-delimited fashion, independently of protein kinase C, and by inositol 1,4,5-triphosphate receptors (ITPR) with bound IP3 (By similarity). May also be activated by internal calcium store depletion. Interacts with ITPR1, ITPR3, MX1 and RNF24 (By similarity). Interacts with JPH2; the interaction is involved in maintaining Ca(2+) homeostasis in skeletal muscle and is mediated by JPH2 'Ser-165' phosphorylation (By similarity). Abundantly expressed in brain. Concentrated in cerebellar Purkinje cells and sparsely localized in cerebellar granule lyer, pontine nuclei and thalamus. Lower levels detected in other tissues. Belongs to the transient receptor (TC 1.A.4) family. STrpC subfamily. TRPC3 sub-subfamily.