A transient receptor potential cation channel TRPC that is a member of a subgroup of subfamily C containing the very similar TRPC3, TRPC6, and TRPC7. They form homomeric or heteromeric nonselective cation channels that generate double-rectifying currents and are activated by diacylglycerol. [ http://www.ncbi.nlm.nih.gov/pubmed/16382100 http://www.ncbi.nlm.nih.gov/pubmed/16460286 http://www.ncbi.nlm.nih.gov/pubmed/17579562 ]