Plants may lack brains, but they have a nervous system, of sorts. And now, plant biologists have discovered that when a leaf gets eaten, it warns other leaves by using some of the same signals as animals. The new work is starting to unravel a long-standing mystery about how different parts of a plant communicate with one another.
|SOURCE| Animal nerve cells talk to each other with the aid of an amino acid called glutamate, which—after being released by an excited nerve cell—helps set off a wave of calcium ions in adjacent cells. The wave travels down the next nerve cell, which relays a signal to the next one in line, enabling long-distance communication.
But scientists were investigating something else when they stumbled on their discovery: how plants react to gravity. They developed a molecular sensor that could detect increases in calcium, which they thought might play a role. They bred the sensor, which glows brighter as calcium levels increase, into a mustard plant called Arabidopsis. They then cut one of its leaves to see whether they could detect any calcium activity.