Corporate Banner
Satellite Banner
Stem Cells, Cellular Therapy & Biobanking
>
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

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

Join For Free

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 2,900+ scientific posters on ePosters
  • More than 4,200+ 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.

Related Content

Cat Stem Cell Therapy Gives Humans Hope
By the time Bob the cat came to the UC Davis veterinary hospital, he had used up most of his nine lives.
Monday, February 08, 2016
Embryonic Switch for Cancer Stem Cell Generation
An international team of scientists report that decreases in a specific group of proteins trigger changes in the cancer microenvironment that accelerate growth and development of therapy-resistant cancer stem cells (CSCs).
Wednesday, December 02, 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
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
Growing Spinal Disc Tissue
Scientists develop new method for growing spinal disc tissue in the lab for combating chronic back pain.
Friday, July 03, 2015
Grant Supports Creation of Patient-Derived Stem Cell Lines
Researchers have received a two-year, $600,000 grant from the National Institute on Aging to develop and study patient-derived stem cell lines.
Thursday, December 12, 2013
Prostate Cancer Stem Cells are a Moving Target
Researchers have discovered how prostate cancer stem cells evolve as the disease progresses, a finding that could help point the way to more highly targeted therapies.
Friday, December 06, 2013
Researchers Change Cell Types by Flipping a Single Switch
New findings have identified a method for changing one cell type into another in a process called forced transdifferentiation.
Friday, December 06, 2013
Understanding a Protein’s Role in Familial Alzheimer’s
Researchers have used genetic engineering of human iPSC’s to specifically and precisely parse the roles of a key mutated protein in causing familial Alzheimer's disease (AD).
Monday, November 18, 2013
Researchers Un-Junking Junk DNA
A study shines a new light on molecular tools our cells use to govern regulated gene expression.
Wednesday, November 13, 2013
$100M gift launches Sanford Stem Cell Clinical Center
T. Denny Sanford has committed $100 million to the creation of the Sanford Stem Cell Clinical Center at the University of California, San Diego.
Wednesday, November 06, 2013
Grafted Limb Cells Acquire Molecular ‘Fingerprint’ of New Location
Findings further creation of regenerative therapies for humans.
Wednesday, October 30, 2013
From Mature Cells to Embryonic-Like Stem Cells
Bioengineers have shown that physical cues can replace certain chemicals when nudging mature cells back to a pluripotent stage.
Tuesday, October 22, 2013
Researchers Develop Stem Cell Therapies for Acute Lung Injury
An estimated 200,000 patients a year have acute respiratory failure in the U.S. and mortality is about 30 to 40 percent.
Monday, October 21, 2013
Single Gene Mutation Linked to Neurological Disorders
Mutation could offer insights into Alzheimer’s, Parkinson’s and Huntigton’s Diseases.
Wednesday, October 16, 2013
Scientific News
Muscles on-a-Chip
This study may help explain why stem cell-based therapies have so far shown limited benefits for heart attack patients in clinical trials.
3-D Printed Lifelike Liver Tissue for Drug Screening
A team led by engineers at the University of California, San Diego has 3D-printed a tissue that closely mimics the human liver's sophisticated structure and function. The new model could be used for patient-specific drug screening and disease modeling.
Therapeutic Approach Gives Hope for Multiple Myeloma
A new therapeutic approach tested by a team from Maisonneuve-Rosemont Hospital (CIUSSS-EST, Montreal) and the University of Montreal gives promising results for the treatment of multiple myeloma, a cancer of the bone marrow currently considered incurable with conventional chemotherapy and for which the average life expectancy is about 6 or 7 years.
Cat Stem Cell Therapy Gives Humans Hope
By the time Bob the cat came to the UC Davis veterinary hospital, he had used up most of his nine lives.
Bile Acid Supports Production of Blood Stem Cells
A research group at Lund University has been able to show that bile acid is transferred from the mother to the foetus via the placenta to enable the foetus to produce blood stem cells.
New Biomarker to Assess Stem Cells Developed
A research team led by scientists from UCL have found a way to assess the viability of 'manufactured' stem cells known as induced pluripotent stem cells (iPSCs). The team's discovery offers a new way to fast-track screening methods used in stem cell research.
Tricked-Out Immune Cells Could Attack Cancer
New cell-engineering technique may lead to precision immunotherapies.
Edited Stem Cells Offer Hope of Precision Therapy for Blindness
Findings raise the possibility of treating blinding eye diseases using a patient's own corrected cells as replacement tissue.
Hacking the Programs of Cancer Stem Cells
All tumor cells are the offspring of a single, aberrant cell, but they are not all alike.
Newfound Strength in Regenerative Medicine
A promising new approach uses direct mechanical stimulation to repair severely damaged skeletal muscles.
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
2,900+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,200+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!