CikA, a Bacteriophytochrome That Resets the Cyanobacterial Circadian Clock

作者：Oliver Schmitz, Mitsunori Katayama, Stanly B. Williams, Takao Kondo, Susan S. Golden · 发表于：Science · 年份：2000 · DOI：10.1126/science.289.5480.765 · 被引用次数：312 · 研究领域：Light effects on plants、Circadian rhythm and melatonin、Photosynthetic Processes and Mechanisms

The circadian oscillator of the cyanobacterium Synechococcus elongatus, like those in eukaryotes, is entrained by environmental cues. Inactivation of the gene cikA (circadian input kinase) shortens the circadian period of gene expression rhythms in S. elongatus by approximately 2 hours, changes the phasing of a subset of rhythms, and nearly abolishes resetting of phase by a pulse of darkness. The CikA protein sequence reveals that it is a divergent bacteriophytochrome with characteristic histidine protein kinase motifs and a cryptic response regulator motif. CikA is likely a key component of a pathway that provides environmental input to the circadian oscillator in S. elongatus.