Figure 5.

Rapid response of the effect of Ca-recoverin to a drop in Ca concentration. Flash response in recoverin at 20 μM Ca (bold trace). During the response shown by the thin trace, Ca concentration of the dialyzing solution was lowered from 20 to 0.5 μM Ca (timing indicated above). Recovery accelerated within 300 ms after the drop in Ca. Myristoylated recoverin at 8.6 μM was present throughout. Flash strength 80 photons/μm². Time constants, τ, were (s): 32, Ca-recoverin; 23, Ca-recoverin after Ca removal. Absolute amplitudes (pA): 54, Ca-recoverin; 51, Ca-recoverin with Ca removal. Junction currents induced by Ca removal have been subtracted.