Related Experiment Video
Updated: Aug 19, 2026

Measurement of 3-Dimensional cAMP Distributions in Living Cells using 4-Dimensional (x, y, z, and λ) Hyperspectral FRET Imaging and Analysis
Published on: October 27, 2020
Ca2+-dependent regulation of cyclic-AMP phosphodiesterase by parvalbumin
Abstract:
Carp parvalbumin has been shown to activate rat brain phosphodiesterase in a Ca2+-dependent manner. The concentration of Ca2+ required for half-maximal stimulation is 1.4 X 10(-7) M, whereas rat testis Ca2+-dependent regulator (CDR) of phosphodiesterase required 1.2 X 10(-6) M Ca2+. The difference in the slopes of the two curves demonstrated that the activation induced by parvalbumin was not the result of a small contamination by CDR. In addition, it has been shown that Ca2+ binding to parvalbumin parallels its activation of phosphodiesterase. These data suggest that Ca2+ must bind to a single specific metal binding site before phosphodiesterase can be fully activated.
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