As time glows by in bacteria

摘要

Populations of ceels can exhibit remarkably precise and able circadian oscillations. But can single cells achieve such precision in the absence of intercellular communication?? For cyanobacteria, it seems so.Have you ever heard of a bacterium with jet lag? The idea might seem absurd; 20 years ago, experts in the field would have thought so too. Bacterial cells were believed to be just too 'simple' to have the biological clocks necessary to regulate daily (circadian) rhythms of gene expression, physiology and behaviour. But things have come a long way since then. We now know that cyanobacteria ― also known as blue-green algae ― have a robust circadian clock system that regulates the expression of all the genes in the organism. In fact, these bacteria are on the cutting edge of research into biological clocks, especially as regards structural studies of clock proteins and rigorous assessments of the evolutionary significance of circadian rhythms. And their utility looks set to continue: on page 81 of this issue, Mihal-cescu and co-workers report data that spotlight cyanobacteria as a new model system for the analysis of circadian rhythms in single cells.