ABSTRACT The several bioluminescence rhythms have been widely
used to characterize the response to various stimuli of the Gonyaulax circadian clock. In
particular, Gonyaulax
responds to changes in light intensity with a phase response curve
(PRC). The magnitude and sign of the phase shifts depend on the light
intensity and the spectral quality of the light in addition to the time
at which the cells are exposed. Different drugs can affect the timing
of the cells by themselves, and can act to modulate the response of the
clock to light. One important class of drugs, the protein synthesis
inhibitors, produces PRCs superficially similar to those induced by
light, with the difficulty in removing the drug after the pulses an
important difference between the two treatments. The Gonyaulax clock is temperature
compensated with a Q10 of 0.85.