Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Newly identified enzyme group converts protein into cellular traffic signal

13.05.2005


An international research team has identified a new group of enzymes that may help uncover how cells direct internal traffic. The discovery has future implications for conditions -- such as polycystic kidney disease, male infertility, behavioral disorders and cancer -- that involve defects in protein fibers called microtubules. The findings will be published in the online journal Science Express on May 12, 2005.



The team was co-led by Jacek Gaertig, associate professor of cellular biology at UGA, and Bernard Eddé of National Center for Scientific Research (CNRS) in France.

Cells have an internal highway system made of fibers called microtubules. Specialized motor proteins slide along these fibers, carrying organelles and other materials to the places they need to go. But how do motor proteins know where to take their cargoes?


The researchers identified a new enzyme group that attaches an unusual molecular tag to a component of the cell’s microtubular highway system. The tag is attached to a localized region of a microtubule and may act like a road sign on the Interstate, directing motor proteins to take the "proper exit" to the nucleus or the cell membrane.

"We’ve known for more than a decade that strings of glutamic acid (an amino acid) are sometimes attached to the side of a protein called tubulin," said Gaertig, one of the senior co-authors on the paper. Tubulin is a component of microtubules. "This modification occurs in all cells but is abundant in neurons in the brain."

Few other proteins are modified in this way. But investigating what the modification does and how it works has been difficult until now.

The authors have identified a new group of enzymes -- called polyglutamylases -- that attach glutamic acid chains of varying length and branching patterns.

Because the enzyme complex is active only for a short window during development in mice, it took a "biochemical tour de force" by collaborators in France to purify it.

In Gaertig’s group, doctoral student Krzysztof Rogowski then identified the enzyme complex’s active subunit and postdoctoral associate Dorota Wloga found genes for these enzymes in many organisms including humans. The researchers also showed that these enzymes can modify just a portion of a microtubular highway, an important discovery that suggests the mechanism for directing cell traffic. The lab studied polyglutamylases from the unicellular pond protist Tetrahymena, a model organism that has abundant modified microtubules and shares many of the same properties of internal cell traffic as animal cells.

"Although it has been known for some time that polyglutamylation occurs, the function of these glutamic acid chains on microtubules have, until now, remained completely obscure," Eve Ida Barak, a program director for the National Science Foundation, said in an email.

Kim Carlyle | EurekAlert!
Further information:
http://www.uga.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>