Movie 1.

A typical TIRF recording from hR1 endo cells co-transfected with pcDNA and mCherry plasmid. Video showing 3 s prior to photolysis of caged ciIP₃ and the following 40 s of activity in Cal520-loaded hR1 endo cells, related to Fig. 7. Photolysis was accomplished by exposure from a 405 nm laser for 1 s (indicated by an asterisk). An image acquired from the same field of view using a 561 nm laser to optically identify mCherry positive cells is also shown.