Kondo T, Ishiura M
Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya, Japan.
Bioessays. 2000 Jan;22(1):10-5. doi: 10.1002/(SICI)1521-1878(200001)22:1<10::AID-BIES4>3.0.CO;2-A.
A circadian clock, with physiological characteristics similar to those of eukaryotes, functions in the photosynthetic prokaryote, cyanobacteria. The molecular mechanism of this clock has been efficiently dissected using a luciferase reporter gene that reports the status of the clock. A circadian clock gene cluster, kaiABC, has been cloned via rhythm mutants of cyanobacterium, Synechococcus, and many clock mutations mapped to the three kai genes. Although kai genes do not share any homology with clock genes so far identified in eukaryotes, analysis of their expression suggests that a negative feedback control of kaiC expression by KaiC generates the circadian oscillation and that KaiA functions as a positive factor to sustain this oscillation. BioEssays 22:10-15, 2000.
一种具有与真核生物相似生理特性的生物钟，在光合原核生物蓝细菌中发挥作用。利用报告生物钟状态的荧光素酶报告基因，已有效地剖析了这种生物钟的分子机制。通过蓝细菌集胞藻的节律突变体克隆了一个生物钟基因簇kaiABC，许多生物钟突变被定位到这三个kai基因上。尽管kai基因与目前在真核生物中鉴定出的生物钟基因没有任何同源性，但对它们表达的分析表明，KaiC对kaiC表达的负反馈控制产生了昼夜节律振荡，而KaiA作为一个正因子维持这种振荡。《生物论文》2000年第22卷，第10 - 15页。
