Researchers Find Tools Needed To Build a Cellular Shredder

May 28, 2009

(PhysOrg.com) -- Yale University researchers have discovered a set of cellular chaperones needed to assemble a proteasome, the cellular workhorse that recycles proteins and is crucial for the existence of all eukaryotic cells.

Even though proteasomes are a target of new generation of cancer drugs and their malfunction contributes to neurodegenerative diseases such as Alzheimer’s disease, little is known about how this complex machine assembles itself within .

Working with yeast, a team led by Mark Hochstrasser, Eugene Higgins Professor of & Biochemistry, discovered four factors called assembly chaperones that are crucial to the construction of a key part of the proteasome complex. Their findings are reported in Friday’s edition of the journal Cell.

“Our discovery of these factors and their initial characterization is just the first step toward understanding how they operate,” Hochstrasser said. “A lot of different proteins have to come together to makes a full proteasome.”

Proteasomes are a sort of cellular shredder, taking specific proteins within the cell and breaking them apart so they will not block cell proliferation or accumulate to toxic levels. A single mammalian cell might have as many as 800,000 proteasomes.

Sometimes, however, proteasomes can shred proteins that would otherwise cause cancer cells to die. A drug that inhibits proteasomes has been approved as a therapy against . Conversely, malfunctions of the proteasome can lead to aggregation of harmful proteins such as those associated with Alzheimer’s disease. Understanding how proteasomes are constructed will help researchers identify mechanisms to intervene in these diseases processes, Hochstrasser said.

Provided by Yale University (news : web)

Explore further: Structure of sodium channels different than previously believed

add to favorites email to friend print save as pdf

Related Stories

Researchers make new finding about how memory is stored

Apr 23, 2008

Researchers at Wake Forest University School of Medicine are the first to show that the location of protein-destroying “machines” in nerve cells in the brain may play an important role in how memories are formed – a ...

Key protein that may cause cancer cell death identified

Jan 16, 2009

Researchers at A*STAR's Institute of Molecular and Cell Biology (IMCB) have become the first to discover and characterize a human protein called Bax-beta (Baxβ), which can potentially cause the death of cancer cells ...

Penn researchers link cell's protein recycling systems

Jun 14, 2007

Many age-related neurological diseases are associated with defective proteins accumulating in nerve cells, suggesting that the cell’s normal disposal mechanisms are not operating correctly. Now, researchers ...

Targeting key proteins of carcinogenesis

Jun 22, 2007

Misfolded and disused proteins are eliminated by a cellular shredder called the proteasome. The cell labels the proteins it wants to dispose with Ubiquitin (Ub) in order to avoid the unwanted degradation of still needed proteins. ...

Recommended for you

Breakthrough points to new drugs from nature

Apr 16, 2014

Researchers at Griffith University's Eskitis Institute have developed a new technique for discovering natural compounds which could form the basis of novel therapeutic drugs.

World's first successful visualisation of key coenzyme

Apr 16, 2014

Japanese researchers have successfully developed the world's first imaging method for visualising the behaviour of nicotine-adenine dinucleotide derivative (NAD(P)H), a key coenzyme, inside cells. This feat ...

User comments : 0

More news stories

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.

Health care site flagged in Heartbleed review

People with accounts on the enrollment website for President Barack Obama's signature health care law are being told to change their passwords following an administration-wide review of the government's vulnerability to the ...

Impact glass stores biodata for millions of years

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...