New Scientist
Image: net_efekt
Under the soil of the cornfield, the rootworm larvae emerge from their eggs and crawl in search of roots to munch on. But their mother chose the wrong field to lay her eggs in. There’s something special about the maize here – it’s armed with a smart weapon designed to target the rootworms.
As the larvae feed, this weapon is released from the plant and enters their gut cells. There it halts production of a vital protein by blocking one specific gene. In the hours that follow, this “gene silencing” weapon spreads to other cells in the larvae’s bodies. At first there is no noticeable effect – the larvae still have reserves of the protein. But within a few days they start dying. Ten days later they are all gone.
This weapon is no ordinary pesticide. It is made of a most surprising substance: RNA. This less-famous relative of DNA has turned out be an extraordinarily versatile molecule. Of the many recent discoveries about it, though, the most surprising is surely that it doesn’t always stay put in cells – it can go walkabout. Some forms of the molecule leave cells and go travelling, carrying vital information that can influence other cells in the same body and, astonishingly, even other organisms.
We’ve only just begun studying this phenomenon but it’s already clear that it will be incredibly useful. Not only can these wandering RNAs be used as pesticides, they can also protect simple animals like honeybees from viruses. The big question, of course, is whether we too can be influenced by foreign RNAs. Read more on newscientist.com…
