Obligatory role of Src kinase in the signaling mechanism for TRPC3 cation channels.

Members of the canonical transient receptor potential (TRPC) subfamily of cation channels are candidates for capacitative and non-capacitative Ca2+ entry channels. When ectopically expressed in cell lines, TRPC3 can be activated by phospholipase C-mediated generation of diacylglycerol or by addition of synthetic diacylglycerols, independently of Ca2+ store depletion. Apart from this mode of regulation, little is known about other receptor-dependent signaling events that modulate TRPC3 activity.

Expression level of the canonical transient receptor potential 3 (TRPC3) channel determines its mechanism of activation.

Studies on the mechanism of activation of canonical transient receptor potential (TRPC) channels have often yielded conflicting results. In the current study, we have investigated the influence of expression level on the mode of regulation of TRPC3 channels. At relatively low levels of expression in DT40 chicken B-lymphocytes, TRPC3 was activated by the depletion of Ca2+ stores.