RNAi scoops medical Nobel

From Nature:

Mello Two US geneticists who discovered one of the fundamental mechanisms by which gene expression is controlled have received a Nobel prize for their achievement. Andrew Fire and Craig Mello, who revealed the process of RNA interference (RNAi) in 1998, will share the US$1.4-million award. Fire, then working at the Carnegie Institution of Washington in Baltimore, Maryland, and Mello, who was at the University of Massachusetts Cancer Center in Worcester, made the discovery when studying the worm Caenorhabditis elegans, a much used workhorse for research geneticists.
Fire, Mello and their team wanted to see whether they could influence the production of muscle protein in the worms by tinkering with the mRNA transcribed from the relevant gene. When they injected more of the naturally produced mRNA, it had no effect. Likewise, when they injected a tailor-made ‘antisense’ sequence to bind to the natural ‘sense’ sequence, nothing happened to the worms.

But when they injected double-stranded RNA made up of both sense and antisense sequences bound together, the worms displayed twitching behaviour similar to that of genetic mutants with no muscle gene at all. They had silenced the gene. Subsequent investigation showed that injecting specific double-stranded RNA can silence any gene, and that you only need to inject a few molecules to do it. When Fire and Mello published their findings in Nature in 1998, a new world was opened to geneticists.

More here. (I am deeply proud of Dr. Mello, who is a colleague and fellow scientist at UMass, Worcester).