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

RNA Molecule Is Behind Behavior Changes Cued by Environment

Published: Thursday, September 05, 2013
Last Updated: Thursday, September 05, 2013
Bookmark and Share
UCSF study may point to key mechanism of cellular memory.

Quick changes in behavior – in worms, at least – can be triggered by a unique form of the molecule RNA acting within the nucleus of a cell, UC San Francisco researchers have discovered.

The finding adds to mounting evidence for the importance of RNA in controlling gene activity, for its likely role in disease and for its potential as a therapeutic target.

Recognition of RNA’s importance has led the National Institutes of Health and other research organizations to fund more research directed toward better understanding the molecule’s role in disease and its therapeutic potential.

In a study published online on Aug. 29 in the journal Cell, scientists led by UCSF’s Noelle L’Etoile, PhD, found that the nerve cells of the tiny nematode worm C. elegans quickly learn to stop following a scent and eventually ignore it after an odor fails to lead the worm to food.

The researchers speculate that a similar biological mechanism involving RNA might drive long-lasting physiological changes in many types of human cells as they adapt to changes in the surrounding environment. “Our work indicates a mechanism by which environmentally relevant experiences may regulate gene expression, thereby shaping behavior in a specific and dynamic fashion,” said L’Etoile, an associate professor in the UCSF School of Dentistry's Department of Cell & Tissue Biology.

Therapeutic Possibilities with RNA Interference

The behavior change is a consequence of a negative feedback triggered inside a nerve cell, the researchers determined.

The particular form of RNA responsible for the rapid behavior change is called endogenous, small interfering RNA (endo siRNA), and until now, nobody had described a dynamic physiological role for it, let alone one that regulates behaviors, according to L’Etoile. So far, endo siRNA has been identified in yeast, worms and fruit flies, but not yet in mammals such as humans.

Endo siRNA is one a several types of short RNA molecules that researchers have discovered engage in “RNA interference.” Although it was not discovered until the late 1990s, nearly 40 years after the genetic code for making proteins from genes was identified, the phenomenon of RNA interference now is known to play an important role in fighting viral infection and in preventing genetic mayhem during reproduction by preventing parts of the genome known as “jumping genes” from moving and disrupting DNA within stable, vital genes.

Scientists’ growing understanding of the scope of RNA interference has inspired new experimental strategies for manipulating gene activity therapeutically.

Worm Nerve Cells are a Window on Basic Biology

Over the past two decades, UCSF researchers – including former UCSF faculty member Cori Bargmann, PhD, now at Rockefeller University – have used the worm as a model for exploring the underlying basis of behaviors.

Among other discoveries, Bargmann found four nerve cells that the worm uses to detect odors in the environment and to track down its favorite food: tasty bacteria. She also found hundreds of odor receptor proteins that the worm uses to detect specific scents.

A decade ago, as a post-doctoral fellow in Bargmann’s lab, L’Etoile cloned a gene for a protein called odr-1, needed for odor recognition.

In the newly published Cell study, the researchers probed how just one nerve cell in the worm responds to the scent of butanone, one of the chemicals that can signal the location of bacteria. Bargmann had earlier discovered that when worms are presented with butanone absent any bacteria, they adapt within an hour and stop gravitating toward the source of the chemical. “This change in behavior indicated a memory formation, and we wanted to know the molecular basis of this,” L’Etoile said.

Endo siRNA remains one of the least understood agents of RNA interference, according to L’Etoile.

It is made from a gene’s specific messenger RNA, the sequence of nucleic acid building blocks that carries the genetic blueprint of a protein to the cell’s protein-making machinery outside the nucleus. As a consequence, endo siRNA specifically targets only that gene, L’Etoile said, unlike other types of RNAs involved in RNA interference. Endo siRNA also acts a step earlier to block gene activity, by getting into the cell’s nucleus and stopping the formation of new messenger RNA, rather than simply by destroying existing messenger RNA in the cell’s cytoplasm.

Endo siRNA specific for the odr-1 gene stops the gene from making the messenger RNA, the researchers found in their new study. L’Etoile’s collaborator, Scott Kennedy, PhD, of the University of Wisconsin, Madison, determined how endo siRNA can ride on specific proteins to get into the nucleus where it can act to turn off genes. Bi-Tzen Juang, PhD, a postdoctoral fellow in L’Etoile’s lab, conducted experiments showing that a protein called EGL-4, acting downstream from odr-1, also is needed for the worm to adapt to the unrewarding butanone signal.

“This mechanism allows an environmental stimulus to potentially dial down the activity of any gene,” L’Etoile said. “Thus any gene may sow the seeds of its own inactivation under the right circumstances.”


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 4,400+ 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
Releasing Cancer Cells for Better Analysis
A new device developed at the University of Michigan could provide a non-invasive way to monitor the progress of an advanced cancer treatment.
Releasing Cancer Cells for Better Analysis
A new device developed at the University of Michigan could provide a non-invasive way to monitor the progress of an advanced cancer treatment.
Apricot Kernels Pose Risk of Cyanide Poisoning
Eating more than three small raw apricot kernels, or less than half of one large kernel, in a serving can exceed safe levels. Toddlers consuming even one small apricot kernel risk being over the safe level.
Cell Transplant Treats Parkinson’s in Mice
A University of Wisconsin—Madison neuroscientist has inserted a genetic switch into nerve cells so a patient can alter their activity by taking designer drugs that would not affect any other cell.
Understanding Female HIV Transmission
Glowing virus maps points of entry through entire female reproductive tract for first time.
Genetic Markers Influence Addiction
Differences in vulnerability to cocaine addiction and relapse linked to both inherited traits and epigenetics, U-M researchers find.
Lab-on-a-Chip for Detecting Glucose
By integrating microfluidic chips with fiber optic biosensors, researchers in China are creating ultrasensitive lab-on-a-chip devices to detect glucose levels.
A lncRNA Regulates Repair of DNA Breaks in Breast Cancer Cells
Findings give "new insight" into biology of tough-to-treat breast cancer.
COPD Linked to Increased Bacterial Invasion
Persistent inflammation in COPD may result from a defect in the immune system that allows airway bacteria to invade deeper into the lung.
Detection of HPV in First-Void Urine
Similar sensitivity of HPV test on first void urine sample compared to cervical smear.
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
4,400+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!