Mori T, Johnson C H
Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA.
J Bacteriol. 2001 Apr;183(8):2439-44. doi: 10.1128/JB.183.8.2439-2444.2001.
In the cyanobacterium Synechococcus elongatus, cell division is regulated by a circadian clock. Deletion of the circadian clock gene, kaiC, abolishes rhythms of gene expression and cell division timing. Overexpression of the ftsZ gene halted cell division but not growth, causing cells to grow as filaments without dividing. The nondividing filamentous cells still exhibited robust circadian rhythms of gene expression. This result indicates that the circadian timing system is independent of rhythmic cell division and, together with other results, suggests that the cyanobacterial circadian system is stable and well sustained under a wide range of intracellular conditions.
在蓝藻聚球藻中，细胞分裂受生物钟调控。生物钟基因kaiC的缺失消除了基因表达节律和细胞分裂时间节律。ftsZ基因的过表达使细胞分裂停止，但不影响生长，导致细胞长成不分枝的丝状体。不分裂的丝状细胞仍表现出强劲的基因表达昼夜节律。这一结果表明，昼夜节律系统独立于有节奏的细胞分裂，并且与其他结果一起表明，蓝藻的昼夜节律系统在广泛的细胞内条件下是稳定且维持良好的。
