14 DAY TRIAL // According to a new scientific investigation, which was conducted by experts at the Massachusetts Institute of Technology (MIT) and the University of California in San Diego (UCSD), it would appear that we have a lot in common with bacteria. A special type of the microorganisms, called cyanobacteria, is known for dividing like clockwork, at very precisely-determined intervals. The group says that the mechanism these cells use is remarkably similar to the circadian clock, the time-keeper in our own bodies, which usually dictates when we go to sleep, and keep track of the day-night succession.
Cyanobacteria have, in previous studies, been determined to cycle through active and resting periods on a 24-hour schedule, in very much the same way humans do. This is largely cased by the fact that their main source of energy is sunlight, which they harness through basic photosynthesis. Therefore, it stands to reason that they are the busiest during the way, when they produce large amounts of energy to last them through the night. In the new investigation, the actual influence of the circadian clock on the way these cyanobacteria undergo cell division – their method of multiplication – has been determined.
“These cells have to keep dividing, and the circadian oscillator regulates when they divide,” explains MIT physics graduate student Bernardo Pando. He is also one of the lead authors of a new scientific paper describing the findings, which was published on March 18, in the online issue of the respected journal Science. “Understanding how cells are dividing is really of fundamental importance,” adds UCSD professor of molecular biology Susan Golden, another author of the journal entry. Whereas normal cell division is good for repairing the body (including in humans and higher animals), any excesses in this process can lead to the development of conditions such as cancer.
During the experiments, the investigators kept track of single bacterial cells, photographing them once every 40 minutes. They labeled a number of proteins suspected of playing a part in the control the circadian rhythm plays on cellular division, and then watched their location. This changed throughout the 24-hour cycle, but within specific patterns. The team determined that, even if more energy (light) is made available to the cells, they divide within certain patterns. The cultures may divide twice per day rather than the usual one time, but even then at one and three quarters of the time frame, respectively, rather than in the middle.