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

Cells, Cell Fragments Move in Opposing Directions

Published: Wednesday, April 03, 2013
Last Updated: Wednesday, April 03, 2013
Bookmark and Share
Like tiny, crawling compass needles, whole living cells and cell fragments orient and move in response to electric fields — but in opposite directions.

Their results, published April 8 in the journal Current Biology, could ultimately lead to new ways to heal wounds and deliver stem cell therapies.

When cells crawl into wounded flesh to heal it, they follow an electric field. In healthy tissue there's a flux of charged particles between layers. Damage to tissue sets up a "short circuit," changing the flux direction and creating an electrical field that leads cells into the wound. But exactly how and why does this happen? That’s unclear.

"We know that cells can respond to a weak electrical field, but we don't know how they sense it," said Min Zhao, professor of dermatology and ophthalmology and a researcher at UC Davis' stem cell center, the Institute for Regenerative Cures. "If we can understand the process better, we can make wound healing and tissue regeneration more effective.”

The researchers worked with cells that form fish scales, called keratocytes. These fish cells are commonly used to study cell motion, and they also readily shed cell fragments, wrapped in a cell membrane but lacking a nucleus, major organelles, DNA or much else in the way of other structures.

In a surprise discovery, whole cells and cell fragments moved in opposite directions in the same electric field, said Alex Mogilner, professor of mathematics and of neurobiology, physiology and behavior at UC Davis and co-senior author of the paper.

It's the first time that such basic cell fragments have been shown to orient and move in an electric field, Mogilner said. That allowed the researchers to discover that the cells and cell fragments are oriented by a "tug of war" between two competing processes.

Think of a cell as a blob of fluid and protein gel wrapped in a membrane. Cells crawl along surfaces by sliding and ratcheting protein fibers inside the cell past each other, advancing the leading edge of the cell while withdrawing the trailing edge.

Assistant project scientist Yaohui Sun found that when whole cells were exposed to an electric field, actin protein fibers collected and grew on the side of the cell facing the negative electrode (cathode), while a mix of contracting actin and myosin fibers formed toward the positive electrode (anode). Both actin alone, and actin with myosin, can create motors that drive the cell forward.

The polarizing effect set up a tug-of-war between the two mechanisms. In whole cells, the actin mechanism won, and the cell crawled toward the cathode. But in cell fragments, the actin/myosin motor came out on top, got the rear of the cell oriented toward the cathode, and the cell fragment crawled in the opposite direction.

The results show that there are at least two distinct pathways through which cells respond to electric fields, Mogilner said. At least one of the pathways — leading to organized actin/myosin fibers — can work without a cell nucleus or any of the other organelles found in cells, beyond the cell membrane and proteins that make up the cytoskeleton.

Upstream of those two pathways is some kind of sensor that detects the electric field. In a separate paper to be published in the same journal issue, Mogilner and Stanford University researchers Greg Allen and Julie Theriot narrow down the possible mechanisms. The most likely explanation, they conclude, is that the electric field causes certain electrically charged proteins in the cell membrane to concentrate at the membrane edge, triggering a response.

The team also included Hao Do, Jing Gao and Ren Zhao, all at the Institute for Regenerative Cures and the UC Davis departments of Ophthalmology and Dermatology. Sun is co-advised by Mogilner and Zhao; Gao is now working at Yunnan Normal University, Kunming, China, and Ren Zhao is at the Third Military Medical University, Chongqing, China.

The work was funded by the National Institutes of Health, the California Institute for Regenerative Medicine and the National Science Foundation.

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 2,800+ scientific posters on ePosters
  • More Than 4,000+ 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 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.

Related Content

RNA-Based Drugs Give More Control Over Gene Editing
CRISPR/Cas9 gene editing technique can be transiently activated and inactivated using RNA-based drugs, giving researchers more precise control in correcting and inactivating genes.
Monday, November 23, 2015
Some 3-D Printed Objects Are Toxic
Researchers at the University of California, Riverside have found parts produced by some commercial 3-D printers are toxic to certain fish embryos.
Monday, November 09, 2015
Artificial Kidney Research Gets A Boost
Development of a surgically implantable, artificial kidney — a promising alternative to kidney transplantation or dialysis for people with end-stage kidney disease — has received a $6 million boost.
Monday, November 09, 2015
Clearest Ever Images of Enzyme that Plays Key Roles in Aging, Cancer
UCLA-led research on telomerase could lead to new strategies for treating disease
Monday, October 19, 2015
Crop Cure
Scientists in new center to use medical research techniques to help food crops withstand drought and climate change.
Friday, October 16, 2015
Rare Childhood Leukemia Reveals Surprising Genetic Secrets
A coalition of leukemia researchers led by scientists from UC San Francisco has discovered surprising genetic diversity in juvenile myelomonocytic leukemia (JMML), a rare but aggressive childhood blood cancer.
Thursday, October 15, 2015
Sustaining Our Salad
Improving lettuce crops is the aim of a new, $4.5 million grant, awarded to University of California, Davis, researchers by the U.S. Department of Agriculture's National Institute of Food and Agriculture.
Thursday, October 15, 2015
Double Enzyme Hit May Explain Common Cancer Drug Side Effect
Mouse study suggests genomic screening before treatment may help prevent anemia.
Wednesday, October 14, 2015
New Autism Genes Are Revealed in Largest-Ever Study
Work draws more detailed picture of genetic risk, sheds light on sex differences in diagnosis.
Wednesday, September 30, 2015
Influenza A Viruses More Likely To Emerge In East Asia Than North America
Novel strains of influenza A are more likely to emerge in East Asia than in North America, according to a global analysis by the One Health Institute at the UC Davis School of Veterinary Medicine and EcoHealth Alliance.
Wednesday, September 30, 2015
Opening the Door to Safer, More Precise Cancer Therapies
New method regulates when, and how strongly, cancer-killing therapeutic T cells are activated.
Tuesday, September 29, 2015
Crunching Numbers to Combat Cancer
UCSF receives $5 million to integrate data from cancer research models.
Wednesday, September 16, 2015
Virus In Cattle Linked To Human Breast Cancer
A new study by UC Berkeley researchers establishes for the first time a link between infection with the bovine leukemia virus and human breast cancer.
Wednesday, September 16, 2015
Ultrafast DNA Diagnostics
New technology developed by UC Berkeley bioengineers promises to make a workhorse lab tool cheaper, more portable and many times faster by accelerating the heating and cooling of genetic samples with the switch of a light.
Monday, August 03, 2015
Scientists Create CRISPR/Cas9 Knock-In Mutations in Human T Cells
In a project spearheaded by investigators at UC San Francisco, scientists have devised a new strategy to precisely modify human T cells using the genome-editing system known as CRISPR/Cas9.
Tuesday, July 28, 2015
Scientific News
High Throughput Mass Spectrometry-Based Screening Assay Trends
Dr John Comley provides an insight into HT MS-based screening with a focus on future user requirements and preferences.
How a Genetic Locus Protects Adult Blood-Forming Stem Cells
Mammalian imprinted Gtl2 protects adult hematopoietic stem cells by restricting metabolic activity in the cells' mitochondria.
Genetic Basis of Fatal Flu Side Effect Discovered
A group of people with fatal H1N1 flu died after their viral infections triggered a deadly hyperinflammatory disorder in susceptible individuals with gene mutations linked to the overactive immune response, according to a recent study.
New Tech Vastly Improves CRISPR/Cas9 Accuracy
A new CRISPR/Cas9 technology developed by scientists at UMass Medical School is precise enough to surgically edit DNA at nearly any genomic location, while avoiding potentially harmful off-target changes typically seen in standard CRISPR gene editing techniques.
The MaxSignal Colistin ELISA Test Kit from Bioo Scientific
Kit can help prevent the antibiotic apocalypse by keeping last resort drugs out of the food supply.
"Good" Mozzie Virus Might Hold Key to Fighting Human Disease
Australian scientists have discovered a new virus carried by one of the country’s most common pest mosquitoes.
Non-Disease Proteins Kill Brain Cells
Scientists at the forefront of cutting-edge research into neurodegenerative diseases such as Alzheimer’s and Parkinson’s have shown that the mere presence of protein aggregates may be as important as their form and identity in inducing cell death in brain tissue.
Closing the Loop on an HIV Escape Mechanism
Research team finds that protein motions regulate virus infectivity.
New Class of RNA Tumor Suppressors Identified
Two short, “housekeeping” RNA molecules block cancer growth by binding to an important cancer-associated protein called KRAS. More than a quarter of all human cancers are missing these RNAs.
Potential Treatment for Life-Threatening Viral Infections Revealed
The findings point to new therapies for Dengue, West Nile and Ebola.
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
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos