Thought to form a receptor-activated non-selective calcium permeant cation channel (PubMed:19936226, PubMed:23291369). 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 (PubMed:26892346). Seems not to be activated by intracellular calcium store depletion.