VR1(E600K) is a ligand-gated cation channel that can be used to activate neurons in an inducible manner; the channel is activated by capsaicin. It is an engineered derivative of a mammalian vanilloid receptor (TRPV1) that has been mutated to carry a E600K amino acid substitution; this mutation increases sensitivity to the capsaicin agonist (PMID:10859346).