Extremophile Yields a Key Cog in Life's Protein Factory

Sep 10, 2009
Artist rendering of a small ribonucleoprotein.

(PhysOrg.com) -- Peering at single molecules within an organism that makes its home near thermal vents, Yale University scientists have discovered the structure of a key player in the creation of protein-making factories in humans.

In the Sept. 11 issue of the journal Science, Susan Baserga, professor of molecular biophysics and biochemistry, genetics, and therapeutic radiology and her colleagues describe the elusive structure of an RNA and protein essential to making ribosomes, which churn out the proteins that carry out most of life’s functions. Malfunctions of this process have been implicated in cancer and as well as in rare genetic disorders that cause infertility and childhood cirrhosis.

Ribosomes carry out the essential business of translating the information encoded in DNA into proteins. The makeup of one of the key players in the process of making ribosomes, the RNA-protein enzymes called box C/D small ribonucleoproteins, had been unknown. Scientists were eager to describe the complex, which is so important to life it is conserved in organisms as diverse as yeast and humans, and even in extremophiles in the domain Archaea.

Baserga’s team decided to look at the archeon, Methanocaldococcus jannaschii, a microbe so hardy it survives in Antarctic ice and boiling thermal vents at the bottom of the ocean. Using single-particle , the research team was able to see that the RNA and enzyme was unexpectedly composed of two RNAs and 4 sets of proteins.

“It looks like a wheat thin with feet,” she said. “When you can discern structure, you can often figure out function.”

The structure of this RNA-protein enzyme is just one piece of the puzzle for understanding how the many factors that contribute to making human ribosomes come together at the right time and place. Mutations in other factors that make ribosomes can disrupt sperm production in men or lead to a rare form of . Also, because production is central to cell growth and division, it is routinely used as a marker to stage cancer progression.

“If you are a cancer cell, you need as many ribosomes as you can get,’’ Baserga said.

Baserga said her lab is already using the findings of this study to further understand how this enzyme is essential to the creation of ribosomal .

Lead researcher on the Science paper was Franziska Bleichert of Yale. Vinzenz M. Unger was the other Yale author of the paper, which included contributors from North Carolina State and Harvard.

Provided by Yale University (news : web)

Explore further: Jumping hurdles in the RNA world

add to favorites email to friend print save as pdf

Related Stories

Bacteria are models of efficiency

Feb 04, 2009

The bacterium Escherichia coli, one of the best-studied single-celled organisms around, is a master of industrial efficiency. This bacterium can be thought of as a factory with just one product: itself. It exists to make c ...

New Mathematical Model Evaluates Efficiency of E. Coli

Feb 04, 2009

The bacterium Escherichia coli, one of the best-studied single-celled organisms around, is a master of industrial efficiency. This bacterium can be thought of as a factory with just one product: itself. It exists to make c ...

Molecular sleuths track evolution through the ribosome

Aug 18, 2008

A new study of the ribosome, the cell's protein-building machinery, sheds light on the oldest branches of the evolutionary tree of life and suggests that differences in ribosomal structure between the three ...

Biologists probe the machinery of cellular protein factories

Sep 13, 2006

Proteins of all sizes and shapes do most of the work in living cells, and the DNA sequences in genes spell out the instructions for making those proteins. The crucial job of reading the genetic instructions and synthesizing ...

Recommended for you

Jumping hurdles in the RNA world

Nov 21, 2014

Astrobiologists have shown that the formation of RNA from prebiotic reactions may not be as problematic as scientists once thought.

New computer model sets new precedent in drug discovery

Nov 18, 2014

A major challenge faced by the pharmaceutical industry has been how to rationally design and select protein molecules to create effective biologic drug therapies while reducing unintended side effects - a challenge that has ...

Finding new ways to make drugs

Nov 18, 2014

Chemists have developed a revolutionary new way to manufacture natural chemicals and used it to assemble a scarce anti-inflammatory drug with potential to treat cancer and malaria.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.