Medicine prize for the discovery of microRNA

MicroRNAs have been shown to be critical to multicellular organisms, including humans, and to how organisms develop and function.

“Victor Ambros and Gary Ruvkun were interested in how different cell types are formed. They discovered that microRNAs, a new class of very small RNA molecules, play a crucial role in gene regulation,” writes the Nobel Assembly.

“Huge Consequences”

When DNA is to be copied, it must first be copied into an almost identical molecule called RNA, which often leads to the formation of protein. But the small microRNA molecules can, put simply, prevent it. They act as an on and off button.

And that has huge consequences, because the proteins are often what build up animals and plants and regulate how we function, says Professor Fredrik Söderbom, who himself researched with one of the prize winners, and continues:

If it is not exactly the right amount of proteins, it is often wrong and it can lead to diseases. So it is extremely important that we get the right amount of proteins in the right cells. And there, microRNAs help control it.

The researchers have taken an interest in a small worm, with the scientific name Caenorhabditis elegans, which was also an important part of the 2006 medicine prize.

In this year’s Nobel Prize, an elegant little organism was the key. This little “elegance” has been used as a model for more than half a century. The worm contains only 1,000 cells, but forms many of the same tissues as in humans, explains Professor Olle Kämpe at a press conference.

“Had given up”

The fact that the worm is so small, yet complex, makes it suitable for studying how different tissues form and develop. The researchers studied each type of mutant strain in the worms, to understand their function and connection to protein production.

When they then compared their respective findings with each other, it led to the groundbreaking discovery, which describes the mechanism of how genes are regulated.

The result was presented in 1993 in the journal Cell.

At first it was thought that microRNA was specific to the worm, but after several years it has been found in other living things. Söderbom thinks that the award winners are well deserved.

I had probably given up a little bit. But it was absolutely right, it was clean, he says.

Facts: This year’s Nobel laureate in physiology or medicine

Victor Ambros is an American molecular biologist, active at the University of Massachusetts Medical School. He is 70 years old, born in Hanover in the state of New Hampshire.

Gary Ruvkun is also an American molecular biologist, active at Massachusetts General Hospital and professor of genetics at Harvard Medical School in Boston. He is 72 years old and from Berkeley, California.

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