Corporate Banner
Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

New Study Sheds Light on How Cells Transport Materials Along Crowded Intercellular 'Highways'

Published: Wednesday, February 06, 2013
Last Updated: Wednesday, December 19, 2012
Bookmark and Share
The study by physicists at WPI and UMass Amherst provides new insights into a cellular system whose failure can lead to neurodegenerative diseases and cancer.

The interior of an animal cell is like a small city, with factories—called organelles—dedicated to manufacturing, energy production, waste processing, and other life functions. A network of intercellular "highways," called microtubules, enables bio-molecular complexes, products, and other cargo to move speedily about the cell to keep this vital machinery humming. A new paper published online in the journal Proceedings of the National Academy of Sciences sheds new light on how cells manage to keep traffic flowing smoothly along this busy transportation network that is vital to the survival of cells and whose failure can lead to a variety of diseases, including Alzheimer's and cancer.

The study, "Motor transport of self-assembled cargos in crowded environments" (http://www.pnas.org/content/early/2012/11/28/1209304109.abstract), is co-authored by Jennifer Ross, assistant professor of physics at the University of Massachusetts Amherst, Erkan Tüzel, assistant professor of physics at Worcester Polytechnic Institute (WPI), and Leslie Conway and Derek Wood, graduate students of physics at UMass Amherst. It examines how proteins called motors (the trucks of the intercellular transport network) cooperate to minimize traffic jams and maximize the distance traveled by cargos.

In the study, the researchers used quantum dots (nanometer-sized semiconductors that reflect brightly in microscopy images) as cargo. In the laboratory, they attached these tiny cargos to individual motor proteins and then allowed those proteins to attach to a microtubule. Motor proteins are able to "walk" along microtubules by attaching and detaching parts of their structure to the microtubule, much like the hand-over-hand motion of a person climbing a rope. The researchers observed how the quantum dots moved along the microtubule as they created more and more traffic by adding more and more motor proteins to the highways of this simplified transportation system.

They found that the dots moved more slowly as the traffic increased, but that they were able to travel farther before becoming detached from the microtubule. They also observed the pausing of the quantum dots, with the number of pauses increasing, but the length of the pauses decreasing, as the concentration of motor proteins is increased. The authors hypothesize that as the concentration of motor proteins increased, several of them became bound to each quantum dot. Much like trucks driving side-by-side down a multilane highway, the motor proteins likely became attached to different protofilaments along the microtubule (microtubules are made of 13 parallel protofilaments arranged into a hollow tube).

As an individual protein encountered an obstacle (another motor protein, for example), the motion of the dot would pause until the force exerted by the other proteins attached to the dot caused it to become detached from the blocked protein. The greater the number of proteins pulling the dot along the microtubule, the greater the force acting on it and the more quickly it would become detached from blocked proteins (and thus, the briefer the pauses in its forward motion).

In this way, motor proteins were able to cooperate to move cargo around roadblocks and to keep cargo attached to the microtubules despite heavy traffic, Tüzel says. "This is the first study to really look at the operation of the intracellular transportation system crowded conditions that are typical of living cells," he noted.

"It is important to understand how this system works and what can keep it from functioning properly because it is vital to the survival of all animal cells and motor proteins that make many fundamental biological processes, such as cell division, possible," he adds. "When the transport mechanism fails to work properly, it can lead to a variety of illnesses, including neurodegenerative diseases like Huntington's and Alzheimer's, and to cancer."


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,400+ scientific posters on ePosters
  • More Than 3,700+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.


Scientific News
Study Finds Brain Chemicals that Keep Wakefulness in Check
Researchers to develop new drugs that promote better sleep, or control hyperactivity in people with mania.
Sorting Through Cellular Statistics
Aaron Dinner, professor in chemistry, and his graduate student Herman Gudjonson are trying to read the manual of life, DNA, as part of the Dinner group’s research into bioinformatics—the application of statistics to biological research.
Playing 'Tag' with Pollution lets Scientists See Who's It
Using a climate model that can tag sources of soot from different global regions and can track where it lands on the Tibetan Plateau, researchers have determined which areas around the plateau contribute the most soot — and where.
Women’s Immune System Genes Operate Differently from Men’s
A new technology reveals that immune system genes switch on and off differently in women and men, and the source of that variation is not primarily in the DNA.
Long Telomeres Associated with Increased Lung Cancer Risk
Genetic predisposition for long telomeres predicts increased lung adenocarcinoma risk.
First Artificial Ribosome Designed
Researchers at the University of Illinois at Chicago and Northwestern University have engineered a tethered ribosome that works nearly as well as the authentic cellular component, or organelle, that produces all the proteins and enzymes within the cell.
High-Resolution 3D Images Reveal the Muscle Mitochondrial Power Grid
NIH mouse study overturns scientific ideas on energy distribution in muscle.
Expanding the Brain
A team of researchers has identified more than 40 new “imprinted” genes, in which either the maternal or paternal copy of a gene is expressed while the other is silenced.
Identifying a Key Growth Factor in Cell Proliferation
Researchers discover that aspartate is a limiter of cell proliferation.
Study Uncovers Target for Preventing Huntington’s Disease
Scientists from Cardiff University believe that a treatment to prevent or delay the symptoms of Huntington’s disease could now be much closer, following a major breakthrough.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,400+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,700+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!