A Biological Clock
By Katrina Marland
Have you ever pulled an all-nighter? If you have, you know that they are nearly always followed by a terrible, dragging fatigue. For the next day, or even several days, you just don’t feel right. That is nature catching up with you. You see, the human body is only meant to function on a 24-hour cycle; some of it active (awake), and some of it dormant (asleep). This is called a circadian rhythm: a biological process that works on a roughly 24-hour cycle. Just about every living thing on Earth shares this cycle, from animals to plants, fungi and even bacteria.
Now, scientists at the University of Edinburgh have pinpointed the genes in plants that regulate their circadian rhythms. They have found that a set of 12 genes and one particular protein work together to help the plant go dormant at night, saving its energy for growth, processing food and other actions that it can only perform during the day when the sun and other conditions are right. Beyond telling the plant when to wake up and when to sleep, the genes and protein make adjustments to the cycle to help the plant change with the seasons, determining when the plant blooms and when it grows.
This discovery is a big step forward in scientists’ ongoing effort to better understand the mechanisms behind plant activity, and what role the circadian rhythm and other functions play in how plants adapt to a changing environment. The knowledge has possible applications in a number of fields, but perhaps most important is helping scientists understand — and possibly even predict — how plants respond to interruptions in their natural cycles. If you have experienced, as many of us have, particularly strange weather patterns lately — here in Washington, D.C., we’ve had 80-degree days in March and our blooms have been out for weeks — it’s easy to see how significant knowledge like that could be.