Navigation Links
Building memories with actin
Date:7/13/2009

Memories aren't made of actin filaments. But their assembly is crucial for long-term potentiation (LTP), an increase in synapse sensitivity that researchers think helps to lay down memories. In the July 13, 2009 issue of the Journal of Cell Biology (www.jcb.org), Rex et al. reveal that LTP's actin reorganization occurs in two stages that are controlled by different pathways, a discovery that helps explain why it is easy to encode new memories but hard to hold onto them.

If you can't seem to forget those ABBA lyrics you heard in seventh grade but can't remember Lincoln's Gettysburg address, the vagaries of LTP might be to blame. Neuroscientists think that the process, in which a brain synapse becomes more potent after repeated stimulation, underlies the formation and stabilization of new memories. LTP involves changes in the anatomy of synapses and dendritic spines, a process that depends on reorganization of the supporting actin cytoskeleton. However, researchers didn't know what controlled these changes.

Rex et al. tackled the question by dosing slices of rat hippocampus with adenosine, a naturally occurring signal that squelches LTP. Adenosine prevents phosphorylation and inactivation of cofilin, an inhibitor of actin filament assembly, the team found. Cofilin's involvement, in turn, implicates signaling cascades headed by GTPases, such as the RhoA-ROCK and Rac-PAK pathways. The researchers showed that a ROCK inhibitor stalled actin polymerization and resulted in a short-lived LTP. A Rac-blocking compound had no effect.

That doesn't mean the Rac-PAK pathway isn't involved in LTP, however. The team discovered that the Rac inhibitor prolonged cells' vulnerability to a molecule that prevents the stabilization of new actin filaments. That result led Rex et al. to conclude that the two pathways exert their effects at different points. The Rho-ROCK pathway initiates the cytoskeletal changes of LTP, and the Rac-PAK pathway solidifies them so that heightened synapse sensitivity can persist. The researchers hypothesize that one pathway encodes memories, while the other makes sure they stick around.


'/>"/>

Contact: Rita Sullivan
news@rupress.org
212-327-8603
Rockefeller University Press
Source:Eurekalert  

Related biology news :

1. Building blocks of life
2. Rebuilding the evolutionary history of HIV-1 unravels a complex loop
3. Building blocks of life formed on Mars
4. Building disease-beating wheat
5. Building the future -- 21st century nano tools to repair the nervous system
6. International workshop to address capacity building for rainforest leaders
7. In Todays Economy, You Can Strengthen Your Company by Building Your Brand
8. Scientists make chemical cousin of DNA for use as new nanotechnology building block
9. UCI awarded $27.2 million for new stem cell building
10. Building on pyramids of trash
11. Manchester clears first hurdle in €170 million biobank building boom
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Building memories with actin
(Date:5/16/2017)... , May 16, 2017   Bridge ... health organizations, and MD EMR Systems , ... development partner for GE, have established a partnership ... Portal product and the GE Centricity™ products, including ... EMR. These new integrations will ...
(Date:4/24/2017)... Janice Kephart , former 9/11 ... Partners, LLP (IdSP) , today issues the following ... March 6, 2017 Executive Order: Protecting the ... be instilled with greater confidence, enabling the reactivation ... applications are suspended by until at least July ...
(Date:4/18/2017)... 2017  Socionext Inc., a global expert in SoC-based imaging and ... the M820, which features the company,s hybrid codec technology. A demonstration ... Probe, Inc., will be showcased during the upcoming Medtec Japan at ... the Las Vegas Convention Center April 24-27. ... Click here for an ...
Breaking Biology News(10 mins):
(Date:6/27/2017)... ... June 27, 2017 , ... According to a recent report ... do not have negative short- or long-term effects on benthic communities. , ... (PCBs) located at the Puget Sound Naval Shipyard & Intermediate Maintenance Facility in ...
(Date:6/26/2017)... ... 26, 2017 , ... The Workgroup for Electronic Data Interchange (WEDI) , ... in healthcare information exchange and a statutory advisor to the U.S. Department of Health ... Office of the National Coordinator for Health Information Technology, will deliver the keynote at ...
(Date:6/23/2017)... ... June 23, 2017 , ... ... all six of their healthcare job boards. As the largest network of ... therapists, and biotechnicians, DocCafe.com and the MedJobCafe.com Health Network work to match ...
(Date:6/22/2017)... Germany (PRWEB) , ... June 22, 2017 , ... ... is taking over the allergy specialists DST Diagnostische Systeme & Technologien GmbH, thereby ... all know someone who suffers from hay fever, urticaria, asthma, atopic eczema or ...
Breaking Biology Technology: