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

Researchers Identify How Cells Control Calcium Influx

Published: Thursday, May 09, 2013
Last Updated: Thursday, May 09, 2013
Bookmark and Share
When brain cells are overwhelmed by an influx of too many calcium molecules, they shut down the channels through which these molecules enter the cells.

Until now, the "stop" signal mechanism that cells use to control the molecular traffic was unknown.

In the new issue of the journal Neuron, UC Davis Health System scientists report that they have identified the mechanism. Their findings are relevant to understanding the molecular causes of the disruption of brain functioning that occurs in stroke and other neurological disorders.

"Too much calcium influx clearly is part of the neuronal dysfunction in Alzheimer's disease and causes the neuronal damage during and after a stroke. It also contributes to chronic pain," said Johannes W. Hell, professor of pharmacology at UC Davis. Hell headed the research team that identified the mechanism that stops the flow of calcium molecules, which are also called ions, into the specialized brain cells known as neurons.

Hell explained that each day millions of molecules of calcium enter and exit each of the 100 billion neurons of the human brain. These calcium ions move in and out of neurons through pore-like structures, known as channels, that are located in the outer surface, or "skin," of each cell.

The flow of calcium ions into brain cells generates the electrical impulses needed to stimulate such actions as the movement of muscles in our legs and the creation of new memories in the brain. The movement of calcium ions also plays a role in gene expression and affects the flexibility of the structures, called synapses, that are located between neurons and transmit electrical or chemical signals of various strengths from one cell to a second cell.

Neurons employ an unexpected and highly complex mechanism to down regulate, or reduce, the activity of channels that are permitting too many calcium ions to enter neurons, Hell and his colleagues discovered. The mechanism, which leads to the elimination of the overly permissive ion channel employs two proteins, α-actinin and the calcium-binding messenger protein calmodulin.

Located on the neuron's outer surface, referred to as the plasma membrane, α-actinin stabilizes the type of ion channels that constitute a major source of calcium ion influx into brain cells, Hell explained. This protein is a component of the cytoskeleton, the scaffolding of cells. The ion channels that are a major source of calcium ions are referred to as Cav1.2 (L type voltage-dependent calcium channels).

The researchers also found that the calcium-binding messenger protein calmodulin, which is the cell's main sensor for calcium ions, induces internalization, or endocytosis, of Cav1.2 to remove this channel from the cell surface, thus providing an important negative feedback mechanism for excessive calcium ion influx into a neuron, Hell explained.

The discovery that α-actinin and calmodulin play a role in controlling calcium ion influx expands upon Hell's previous research on the molecular mechanisms that regulate the activity of various ion channels at the synapse.

One previous study proved relevant to understanding the biological mechanisms that underlie the body's fight-or-flight response during stress.

In work published in the journal Science in 2001, Hell and colleagues reported that the regulation of Cav1.2 by adrenergic signaling during stress is performed by one of the adrenergic receptors (beta 2 adrenergic receptor) directly linked to Cav1.2.

"This protein-protein interaction ensures that the adrenergic regulation is fast, efficient and precisely targets this channel," Hell said.

"We showed that Cav1.2 is regulated by adrenergic signaling on a time scale of a few seconds, and this is mainly increasing its activity when needed, for example during danger, to make our brain work faster and better. The same channel is in the heart, where adrenergic stimulation increases channel/Ca influx activity, increasing the pacing and strength of our heart beat to meet the increased physical demands during danger."


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 3,000+ scientific posters on ePosters
  • More Than 4,500+ 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

Fructose Alters Hundreds of Brain Genes
UCLA scientists report that diet rich in omega-3 fatty acids can reverse the damage.
Tuesday, April 26, 2016
Study Yields the Key to Effective Personalized Medicine
A team of UCLA bioengineers and surgeons has taken a major step toward making personalized medicine a reality.
Monday, April 11, 2016
Tracking RNA in Live Cells
Technique may open doors to new treatments for many conditions, from cancer to autism.
Friday, March 18, 2016
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
Crowdfunding the Fight Against Cancer
From budding social causes to groundbreaking businesses to the next big band, crowdfunding has helped connect countless worthy projects with like-minded people willing to support their efforts, even in small ways. But could crowdfunding help fight cancer?
Monday, February 08, 2016
Toxic Pollutants Found in Fish Across the World's Oceans
Scripps researchers' analysis shows highly variable pollutant concentrations in fish meat.
Friday, January 29, 2016
Key Enzyme in Pierce’s Disease Grapevine Damage Uncovered
UC Davis plant scientists have identified an enzyme that appears to play a key role in the insect-transmitted bacterial infection of grapevines with Pierce’s disease, which annually costs California’s grape and wine industries more than $100 million.
Wednesday, January 13, 2016
Science Magazine Names CRISPR ‘Breakthrough of the Year’
In its year-end issue, the journal Science chose the CRISPR genome-editing technology invented at UC Berkeley 2015’s Breakthrough of the Year.
Monday, December 21, 2015
Genome Sequencing May Save California's Legendary Sugar Pine
The genome of California’s legendary sugar pine, which naturalist John Muir declared to be “king of the conifers” more than a century ago, has been sequenced by a research team led by UC Davis scientists.
Thursday, December 17, 2015
Cellular “ORACLs” to Aid Drug Discovery
New approach for finding therapeutics is inspired by face-recognition software.
Wednesday, December 16, 2015
New Virus Disovered, Linked To Hepatitis C
Study is first to reveal entire genetic makeup of human pegivirus 2.
Tuesday, December 15, 2015
CRISPR-Cas9 Helps Uncover Genetics of Exotic Organisms
A new study illustrates the ease with which CRISPR-Cas9 can knock out genes in exotic animals to learn how those genes control growth and development.
Friday, December 11, 2015
UC Davis Cracks the Walnut Genome
Scientists at the University of California, Davis, have for the first time sequenced the genome of a commercial walnut variety.
Friday, December 11, 2015
‘Purity’ Of Tumor Samples May Significantly Bias Genomic Analyses
Non-cancerous tumor components influence research findings, clinical classifications, study shows.
Monday, December 07, 2015
New Method for Screening Cancer Cells
Parallel microfiltration could lead to better treatments for a number of diseases, UCLA-led study says.
Thursday, December 03, 2015
Scientific News
Improving Natural Killer Cancer Therapy
Vanderbilt University researchers discover transcription factor critical for NK cell expansion. Findings could lead to increased therapeutic efficacy.
Molecular Mechanism For Generating Specific Antibody Responses Discovered
Study could spur more ways to treat autoimmune disease, develop accurate vaccines.
Monovar Drills Down Into Cancer Genome
Rice, MD Anderson develop program to ID mutations in single cancer cells.
It’s Now Easier To Go With The Flow
Rice University tool simplifies comparison of flow cytometry data for laboratories.
Autism and Cancer Share a Remarkable Number of Risk Genes
Researchers with the UC Davis Comprehensive Cancer Center, MIND Institute identify more than 40 common genes.
Number Of Known Genetic Risk Factors For Endometrial Cancer Doubled
An international collaboration of researchers has identified five new gene regions that increase a woman’s risk of developing endometrial cancer, one of the most common cancers to affect women, taking the number of known gene regions associated with the disease to nine.
Genetic Variant May Help Explain Why Labradors Are Prone To Obesity
A genetic variation associated with obesity and appetite in Labrador retrievers – the UK and US’s favourite dog breed – has been identified by scientists at the University of Cambridge. The finding may explain why Labrador retrievers are more likely to become obese than dogs of other breeds.
FNIH Launches Project to Evaluate Biomarkers in Cancer Patients
Company has announced that it has launched a new project to evaluate the effectiveness of liquid biopsies as biomarkers in colorectal cancer patients.
Flowering Regulation Mechanism Discovered
Monash researchers have discovered a new mechanism that enables plants to regulate their flowering in response to raised temperatures.
Turning Skin Cells into Heart, Brain Cells
In a major breakthrough, scientists at the Gladstone Institutes transformed skin cells into heart cells and brain cells using a combination of chemicals.
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
3,000+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,500+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!