Navigation Links
X-linked mental retardation protein is found to mediate synaptic plasticity in hippocampus
Date:10/19/2011

Cold Spring Harbor, NY Scientists at Cold Spring Harbor Laboratory (CSHL) have solved part of a puzzle concerning the relationship between changes in the strength of synapses the tiny gaps across which nerve cells in the brain communicate and dysfunctions in neural circuits that have been linked with drug addiction, mental retardation and other cognitive disorders.

A team led by CSHL Professor Linda Van Aelst has pieced together essential steps in a signaling cascade within excitatory nerve cells that explains a key phenomenon called longterm depression, or LTD. The "depression" in question has nothing to do with the human illness with that name. Rather, it refers to a tamping-down of the strength of individual synapses what scientists call synaptic plasticity.

The mechanism behind LTD is called endocytosis. It involves a retraction of receptors where neurotransmitters can "dock." Van Aelst and colleagues have demonstrated how LTD works following activation of a class of receptors called group I metabotrobic glutamate receptors, or mGluRs.

It was known that longterm depression mediated by mGluRs depended in part on the rapid synthesis of specific proteins. Yet the identity of these proteins had largely remained a mystery. The CSHL scientists have now shown that locally rapid production of a protein called oligophrenin 1 (OPHN1) follows activation of group I mGluRs. OPHN1 in turn was shown to mediate LTD in hippocampal nerve cells, by interacting with yet another protein called EndophilinA2/3.

The result of this cascade of intracellular signals was dramatic: persistent removal of AMPA-type receptors at the excitatory synapse, and the onset of LTD. When rapid production of OPHN1 was blocked, mGluR-dependent LTD did not occur. These findings appear online today ahead of print in the journal Neuron.

Van Aelst explained the significance of the finding. "OPHN1 has two important functions that we know about. One is early in development, after synapses have appeared in the emerging nervous system. In this phase, OPHN1 in concert with other factors stabilizes receptors at synapses, and thus is essential in maintaining the structure of these essential features of neural circuitry.

"Our new findings show another vital role for OPHN1, later in development and into maturity. We assume that in response to behavioral stimuli we aren't yet sure what kind mGluRs are activated, setting off the series of steps that we identified: rapid upregulation of OPHN1, which binds to EndophilinA2/3, which in turn mediates the long-term removal of AMPA receptors."

OPHN1 is known to be associated with X-linked mental retardation and with other cognitive and behavioral deficits. The team hypothesizes that OPHN1-related changes in plasticity such as those described in their new work may be causally related to such pathology. They are investigating this possibility in their current work.


'/>"/>

Contact: Peter Tarr
tarr@cshl.edu
516-367-8455
Cold Spring Harbor Laboratory
Source:Eurekalert

Related biology news :

1. Polar bears ill from accumulated environmental toxins
2. Can indigenous peoples be relied on to gather reliable environmental data?
3. New data-mining effort launched to study mental disorders
4. Seed time-capsule will aid study of plant evolution amid environmental change
5. Decline and recovery of coral reefs linked to 700 years of human and environmental activity
6. Control gene for developmental timing discovered
7. JoVE grants developing countries access to experimental videos
8. Fast-evolving genes control developmental differences in social insects
9. EPA grants help Wayne State researchers stave off Great Lakes environmental invaders
10. Cells derived from pluripotent stem cells are developmentally immature
11. Genomewide mapping reveals developmental and environmental impacts
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/3/2016)... May 3, 2016  Neurotechnology, a provider of ... MegaMatcher Automated Biometric Identification System (ABIS) , a ... projects. MegaMatcher ABIS can process multiple complex biometric ... combination of fingerprint, face or iris biometrics. It ... and MegaMatcher Accelerator , which have ...
(Date:4/26/2016)... 2016 Research and Markets has ... Market 2016-2020"  report to their offering.  , ,     ... The analysts forecast the global multimodal biometrics market ... the period 2016-2020.  Multimodal biometrics is ... as the healthcare, BFSI, transportation, automotive, and government ...
(Date:4/14/2016)... Israel , April 14, 2016 ... Authentication and Malware Detection, today announced the appointment of ... assumed the new role. Goldwerger,s leadership appointment ... on the heels of the deployment of its platform ... BioCatch,s behavioral biometric technology, which discerns unique cognitive and ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... Apellis Pharmaceuticals, Inc. today announced positive ... its complement C3 inhibitor, APL-2. The trials were ... studies designed to assess the safety, tolerability, pharmacokinetics ... healthy adult volunteers. Forty subjects were ... dose (ranging from 45 to 1,440mg) or repeated ...
(Date:6/23/2016)... 23, 2016 On Wednesday, June 22, ... down 0.22%; the Dow Jones Industrial Average edged 0.27% lower ... 2,085.45, down 0.17%. Stock-Callers.com has initiated coverage on the following ... Therapeutics (NASDAQ: NKTR ), Aralez Pharmaceuticals Inc. (NASDAQ: ... BIND ). Learn more about these stocks by accessing ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... a new line of intelligent tools designed, tuned and optimized exclusively for Okuma ... 12–17 in Chicago. The result of a collaboration among several companies with expertise ...
(Date:6/22/2016)... DIEGO , June 22, 2016 ... that will allow them to produce up to ... from one lot within one week. These high-quality, ... time laboriously preparing cells and spend more time ... possible through a proprietary, high-volume manufacturing process that ...
Breaking Biology Technology: