Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Getting one's protein in a bunch -- When quality control fails in cells

18.01.2007
Over time, a relatively minor mistake in protein production at the cellular level may lead to serious neurological diseases.

But exactly how the cell avoids such mistakes has remained unclear until now. Researchers at Ohio State University found the mechanism that prevents such errors, and explain their findings in the Proceedings of the National Academy of Sciences.

“Cells normally make a certain amount of mutant proteins, and use a series of degradation and recycling steps to get rid of them,” said Michael Ibba, the study's lead author and an associate professor of microbiology at Ohio State University.

“But sometimes the cell produces more mutations than it can handle. That buildup can overwhelm the cell's ability to eliminate these mutants.”

Left unchecked, these errors result in the buildup of faulty proteins within the cell. This buildup happens during translation, a process that cells use to make usable proteins. Over time, the researchers believe that the accumulated proteins might cause neurological diseases, such as Alzheimer's and Parkinson's.

Scientists know that cells use many enzymes to carry out translation properly. The enzymes that make the building blocks for translation carefully check for errors before proteins are made. If they find an error, they instruct the cell to destroy these building blocks, which are called aminoacyl-tRNAs. Cells break down these aminoacyl-tRNAs through a process called hydrolysis, in which one compound is split into other compounds in a reaction that uses water.

Ibba and his team work with a special family of enzymes called the aminoacyl-tRNA synthetases. These enzymes select the amino acids inside the cell that are used for producing proteins.

Ibba and his colleagues used a specific synthetase, phenylalanyl-tRNA synthetase, to investigate what happens when the wrong amino acid is selected. They carried out their experiments in a strain of E. coli bacteria cells.

They changed certain components of the translation process and found that the replacements halved hydrolysis, and in some cases reduce hydrolysis by as much as 90 percent. In other experiments, the researchers also slightly modified the protein. Further tests showed that this alteration left the modified enzymes incapable of preventing mistakes during protein production.

“It revealed an essential function for this group of enzymes in hydrolysis,” Ibba said.

In related work, Ibba and other researchers have found that bacteria grow poorly or die when this enzymatic step is missing.

“We knew it was an important process for the cell, but until this study, we didn't know exactly why it was so important,” Ibba said. “Other researchers have actually disrupted this process in mice, and found that it leads to neurodegenerative diseases resembling Alzheimer's and Parkinson's.”

Ibba and his team face more challenges. They want to know precisely how cells correct for these mistakes, and knowing this may give them insight to neurological diseases.

“The key to efficient cell growth is to limit the level of mistakes to a tolerable amount,” Ibba said. “In spite of all its checks and balances, a cell isn't perfect. Even though textbooks tell you that gene expression is flawless, this just isn't possible in real life.

“Ultimately – and it's a long way off – we hope to develop a way to therapeutically correct for these errors,” he said. “If we understand how these diseases start, and it relates to mistakes in the mechanism we studied, then there may be a means to try and correct these mistakes.”

Ibba conducted the study with Ohio State colleagues Jiqiang Ling, a graduate research associate in the Ohio State Biochemistry Program, and Hervé Roy, a postdoctoral researcher in microbiology.

This study was supported by a grant from the National Science Foundation.

Michael Ibba | EurekAlert!
Further information:
http://www.osu.edu

Further reports about: Error Protein Translation aminoacyl-tRNA hydrolysis

More articles from Life Sciences:

nachricht Topologische Quantenchemie
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

nachricht Topological Quantum Chemistry
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Ultrathin device harvests electricity from human motion

24.07.2017 | Power and Electrical Engineering

Scientists announce the quest for high-index materials

24.07.2017 | Materials Sciences

ADIR Project: Lasers Recover Valuable Materials

24.07.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>