Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify enzyme that may turn fleeting experience into lasting memory

12.11.2003


The enzyme that can help turn a one-time experience into a long-term memory has been identified in mice, researchers at Wake Forest University Baptist Medical Center reported today at the annual meeting of the Society for Neuroscience in New Orleans. Ashok Hegde, Ph.D., of Wake Forest described the researchers’ work and proposed a theory for how lasting memories are formed, a process that involves the enzyme known as protein kinase C.



"One of the hallmarks of memories that last very long is a close association with emotion," Hegde said in an interview. Hegde and colleagues studied female mice, which, with only one exposure at mating, can later recognize their partner’s scent. After mating, a female mouse exposed to the scent of a strange male will not continue her pregnancy. But a female exposed to her partner’s scent even a month after mating will continue her pregnancy. This suggests that the female somehow memorized her partner’s scent during the process of mating.

"The good thing about this model," Hegde said, "is that it’s simple and robust. The memory is unambiguous, and it forms after just one event." In Hegde’s model, formation of the lasting memory in the female mouse requires that olfactory (smell) information about her partner coincide with sensory information about the mating. The information is carried by separate pathways, one involving the neurotransmitter glutamate, the other norepinephrine.


Norepinephrine, which is closely related to adrenaline, is a chemical released in the brain during emotional or exciting situations. If it does play a role in humans’ being able to vividly remember details of an experience from decades ago--where people were when they heard news of President Kennedy’s assassination, for example--the question for researches is how.

"There is a threshold for memory storage," Hegde said. "The brain has to decide what is important for long-term storage. We’re trying to understand how norepinephrine leads to strong-memory formation."

When a memory is formed, structural changes take place at synapses, the connections between nerve cells. Proteins synthesized by genes in the nerve cells cause these changes. Generally speaking, the stronger the connections among synapses, the more lasting the memory. Hegde and his colleagues--Jian Mu, M.D., Dwayne W. Godwin, Ph.D., and Chenghai Dong, M.D., Ph.D., all of the Department of Neurobiology and Anatomy--collected data from the mouse brain to suggest how norepinephrine serves as a "gatekeeper" to allow memories to form under certain circumstances.

Their research suggests that the enzyme protein kinase C plays a fundamental role in turning the female’s experience of mating into a long-term memory of her partner’s scent. Protein kinase C activates genes to express certain proteins. How protein kinase C is linked to gene expression in nerve cells is the subject of a related study by Cristian Skinner, a graduate student in the Hegde lab.

"We’ve known for a long time that you need gene expression to launch protein synthesis, which is necessary to change the synaptic connections that underlie memory," Hegde said. "This could help look at how genes work to form new connections among synapses."

In collaboration with Josyf Mychaleckyj, D.Phil., of the Wake Forest Center for Human Genomics, Hegde said, the human and mouse genomes--both of which have been completely sequenced--are systematically being searched discover genes that have a critical role in long-term memory. Also, Hegde and his assistant, Thuy Smith, are using gene chips that can screen thousands of genes at the same time to identify the "memory" genes in mice.

"The details might be different in mice and people," Hegde said, "but we think the mechanism will be the same."

Karen Richardson | EurekAlert!
Further information:
http://www.wfubmc.edu/

More articles from Life Sciences:

nachricht New eDNA technology used to quickly assess coral reefs
18.04.2019 | University of Hawaii at Manoa

nachricht New automated biological-sample analysis systems to accelerate disease detection
18.04.2019 | Polytechnique Montréal

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

Im Focus: Researchers 3D print metamaterials with novel optical properties

Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna

A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

New automated biological-sample analysis systems to accelerate disease detection

18.04.2019 | Life Sciences

Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

18.04.2019 | Physics and Astronomy

New eDNA technology used to quickly assess coral reefs

18.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>