（１） Field: Biology/Life Science Session Topic: Introductory Speaker:
... rotation of the earth. This simply suggests circadian rhythm is an essential
physiology of all organisms to survive on this planet. In Latin, “circa” and “dian”
mean “approximate” and “day”, respectively. The circadian rhythm is indeed a
fundamental physiological function observed in almost all orga ...
highlighted topics - American Journal of Physiology
... ambient light intensity as the preeminent signal for
entraining circadian rhythms to local geophysical time.
In mammals, the retina is required for photic entrainment, but the responsible visual system is anatomically and physiologically distinct from the visual systems for oculomotor function and i ...
kaiA is a gene in the ""kaiABC"" gene cluster that plays a crucial role in the regulation of circadian rhythm in bacteria, such as the cyanobacterium Synechococcus elongatus. For these bacteria, regulation of kaiA expression is critical for circadian rhythm, which determines the twenty-four hour biological rhythm. In addition, KaiA functions with a negative feedback loop in relation with kaiB and KaiC. The kaiA gene makes KaiA protein that enhances phosphorylation of KaiC while KaiB inhibits activity of KaiA.