Nobel Prize for medicine- Good article,Ameet

[Guest guest]

That was a great reading stuff,Ameet.

Thanks,although late in doing so,for this mail,but truly very encouraging bit.

Particularly,b'cos, we ophthalmologists, too would love to have some new

developments in our presently,frankly.. not a curable blinding condition ..of

Age related Macular Degeneration..

Shyam(84)

Nobel Prize for medicine

Yesterday, they announced the Nobel Prize for Medicne and it was won for

RNAi or RNA interference... a technique commonly used by research scientists

for gene silencing... when conducting studies on gene and protein

expression. In today's world, RNAi has led to several ground breaking

discoveries, and its importance will only increase in the years to come.

Here's a profile of the two scientists who have won the Nobel Prize for

Medicine for RNAi

Ameet 1993

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October 3, 2006

2 Americans Win Nobel for RNA Work

By NICHOLAS WADE

This year's Nobel Prize in Physiology or Medicine has been awarded to two

American researchers, Z. Fire and Craig C. Mello, for a far-reaching

discovery about how genes are controlled within living cells.

The discovery was made in 1998, only eight years ago. It has been recognized

with unusual speed by the Nobel Foundation in Stockholm, which sometimes

lets decades elapse before awarding its accolade. The foundation's caution,

born of the fear of giving immediate recognition to research that may prove

unfounded, may have been dispelled this year by the evident promise of the

new field, several scientists said.

The finding by Drs. Fire and Mello made sense of a series of

puzzling results obtained mostly by plant biologists, including some who

were trying to change the color of petunias. By clarifying what was

happening, they discovered an unexpected system of gene regulation in living

cells and began an explosive phase of research in a field known variously as

RNA interference or gene silencing.

This natural method of switching genes off has turned out to be a superb

research tool, allowing scientists to understand the role of new genes by

suppressing them. The method may also lead to a new class of drugs that

switch off unwanted processes in disease. Two gene-silencing drugs designed

to treat macular degeneration are already in clinical trials.

" This was such an obvious Nobel, on everybody's list of discoveries that

would receive the prize soon, " said Dr. Cech, an expert on RNA and

president of the Medical Institute.

Dr.

Bruce Stillman, president of the Cold Spring Harbor Laboratory on Long

Island, said the prize was to recognize a new field of research, which has

had " a spectacular birth and expansion, " as well as the discovery by Drs.

Fire and Mello that started it.

Dr. Fire, now at Stanford University, worked at the Carnegie Institution of

Washington when he made the discovery. Dr. Mello, a frequent collaborator,

is at the University of Massachusetts Medical School in Worcester. Both are

" worm people, " as scientists who do their biology in the roundworm

Caenorhabditis elegans call themselves.

Prior to their discovery, plant biologists over many decades had found odd

exceptions to Mendel's

laws of heredity, including some unexplained effects produced by injecting

RNA, the less-well-known cousin of DNA, into plants. Both are chemicals

called nucleic acids, but DNA is longer and more stable and is used by the

cell for the archival function of storing genetic information. RNA is

shorter and more active, and performs many of the cell's more difficult

tasks, like making copies of the genes in DNA and directing the synthesis of

the proteins specified by the genes.

The plant biologists supposed that injecting new RNA might somehow interfere

with the protein-synthesizing process but did not understand how to make

this happen reliably.

Drs. Fire and Mello made a decisive advance by showing in roundworms that

the injected RNA had to be double-stranded and that the sequence of chemical

units had to be the same as or very similar to those of the gene being

singled out. Under these conditions, any gene in the roundworm could be

switched off by injecting double-stranded RNA with a sequence of units that

corresponded to those in part of the gene's DNA.

Other scientists soon figured out the evolutionary reason for this curious

mechanism. It is a defense against viruses, many of which have

double-stranded RNA as their genetic material. When a virus enters a cell,

its RNA is chopped up and the fragments are used to battle the virus itself.

The cell takes one strand of each fragment and tests all the messenger-RNA's

- those that direct synthesis of proteins - to see if they match it. Only

the virus's RNA's will match, and

they are destroyed before they can start making the virus's proteins.

The perceived importance of the Fire-Mello finding increased even more when

other researchers discovered that it had a second dimension. It seemed that

cells, having evolved this handy mechanism for suppressing a virus's genes,

then adapted it to controlling their own genes.

Both plants and animals, probably independently, evolved genes that do not

make proteins but simply generate an RNA molecule that loops back on itself

to form a hairpin twist similar to a virus's double-stranded RNA. These

RNA's, known as micro-RNA's, use the same gene-silencing mechanism as is set

off by viruses, and ratchet down the activity of many of the cell's own

genes.

The genes that make micro-RNA's are a novel class, quite different from the

conventional genes that direct the synthesis of proteins. Researchers are

now busily

exploring how many exist in the human and other genomes. Micro-RNA genes

seem to be important in processes like embryonic development and in cancer.

Gene silencing and micro-RNA's have become overnight a major field of

biological research, and one that may well attract other Nobel Prizes in the

future.

" I think it will be applied quite broadly in anticancer therapies in the

next 10 years, " Dr. Stillman said.

Given that scientists are divided into communities who work on particular

organisms, this year's Nobel Prize is being crowed over by worm people, who

also enjoyed a big victory with the 2002 Nobel Prize. It may be less welcome

to weed people - those who work on

mustard and other plant species - who were passed over despite having laid

the basis of the field.

" In some ways, it's a little disappointing not to see plants recognized, "

said Martienssen, a plant geneticist at the Cold Spring Harbor

Laboratory.

Was it unfair for plant biologists to be excluded from the Nobel Prize,

which can be given to up to three winners? " You have to say they had their

chance, and yes, it was interesting biology, but they didn't trace it to

double-stranded RNA, " Dr. Cech said. " The field exploded after the Fire and

Mello paper. "

Dr. Fire was born in 1959 and grew up in Sunnyvale, Calif. His father is a

Silicon Valley engineer. " Coming from a household with a respect for

learning was most important, " he said. He said he did not expect the prize

to change his life of teaching and doing research. But the prize means that

" one can open public debate

on something and people will listen, " he said.

Dr. Mello, born in 1960, also comes from a scientific family. His father is

a paleontologist and was the first in his family to go to college. After

yesterday's interruptions, Dr. Mello said, " I hope I can get right back to

work - I'm still young, as my mom pointed out. "

He and Dr. Fire began collaborating in the late 1980's because they had

developed similar techniques for working on the roundworm. Their

partnership, though long distance, is still in effect. " We spend hours and

hours sharing information and talking about our work, so long that my ear

would hurt, " Dr. Mello said.