Montreal scientists unlock mystery of early molecular mechan

Post Reply
User avatar
Gawdzilla Sama
Stabsobermaschinist
Posts: 151265
Joined: Thu Feb 26, 2009 12:24 am
About me: My posts are related to the thread in the same way Gliese 651b is related to your mother's underwear drawer.
Location: Sitting next to Ayaan in Domus Draconis, and communicating via PMs.
Contact:

Montreal scientists unlock mystery of early molecular mechan

Post by Gawdzilla Sama » Thu Feb 26, 2009 3:28 pm

Montreal scientists unlock mystery of early molecular mechanism



Two Montreal researchers have proposed a new theory for a question that has long vexed evolutionary biologists: How did a mechanism thought to help build life self-assemble?

Sergey Steinberg, a biochemistry professor at the University of Montreal, found the answer in the ribosome, a relatively large mechanism within the cell that takes RNA instruction and builds proteins.

His discovery, made with student Konstantin Bokov, has been published in the scientific journal Nature.

Scientists have long wondered how chemicals spontaneously came together to create proteins before life itself began.

Steinberg and Bokov's theory fills in a critical step in how life got started four billion years ago, said Stephen Michnick, the Canada Research Chair in Integrative Genomics at the University of Montreal.

A key breakthrough came when Steinberg found that chemicals could spontaneously come together and form something as complex as a ribosome. Previous theories had suggested only simple proteins could form spontaneously.

This had been shown in a seminal experiment in the 1950s in which basic chemicals were combined in a flask, heated and zapped with electricity, creating basic proteins as a result.

But proving that chemicals can spontaneously form simple proteins did not prove that spontaneous action could create more complex mechanisms.

"In the absence of such explanations, some people could imagine unseen forces at work when such complex structures emerge in nature," said Steinberg.

Steinberg was able to show otherwise. He found the ribosome was put together using relatively simple structural rules, a bit like a three-dimensional puzzle. For critics who ask why spontaneous formation didn't lead to something other than the ribosome, Steinberg used mathematical models to show there was no other possibility. The ribosome simply wouldn't hold together if it were constructed any other way.

"The assembly followed rules that were logical and for which there were no alternatives," said Michnick. "This forces us to think about bigger structures. This type of thinking is important to understanding all sorts of structure."

For instance, the next step might be to consider why proteins begin to form wrongly spontaneously.

Several neurodegenerative diseases occur when proteins start to malform, said Michnick. Steinberg's research could give insight in how that happens, and why.
Image
Ein Ubootsoldat wrote:“Ich melde mich ab. Grüssen Sie bitte meine Kameraden.”

User avatar
Psi Wavefunction
Cекси техническая лаборатория
Posts: 1880
Joined: Thu Feb 26, 2009 10:06 am
About me: I kill threads WITH SCIENCE!

I like Crascuits. :coffee:
Location: Vancouver
Contact:

Re: Montreal scientists unlock mystery of early molecular mechan

Post by Psi Wavefunction » Fri Feb 27, 2009 9:59 am

Oooh, I saw that when skimming through last week's Nature... :cheers:

rRNA is pretty cool... actually, some believe the ribosomal proteins are simply hitching a ride on the actual functioning part -- the RNA. Basically, if a protein happens to accidentally bind to a piece of RNA, and if this binding would stabilise a subsequent mutation that would otherwise be lethal... the protein suddenly becomes 'essential' and finds itself a niche. Ribosomal RNA was at one point most likely capable of doing all the work without the proteins, but over time it degraded by allowing 'stabilising' proteins to hitch along.

Did that make any sense?


Anyway, the original paper was a bit too biochemical for my tastes, but perhaps I may actually add it to my ever-growing queue... :doh: :coffee:

Post Reply

Who is online

Users browsing this forum: No registered users and 16 guests