Navigation Links
UC Davis researchers visualize formation of a new synapse
Date:6/17/2009

(SACRAMENTO, Calif.) A protein called neuroligin that is implicated in some forms of autism is critical to the construction of a working synapse, locking neurons together like "molecular Velcro," a study lead by a team of UC Davis researchers has found.

Published online in the June issue of the journal Neural Development, the study is accompanied by groundbreaking images that are the first to show two neurons coming together using neuroligin to construct a new synapse.

"Previous research has suggested that neuroligin is critical for the formation and stabilization of synapses," said Kimberley McAllister, an associate professor of neurology in the UC Davis School of Medicine and a researcher at the UC Davis Center for Neuroscience. "Our work suggests that neuroligin is one of the first molecules to be recruited to new synapses and that it also acts as Velcro to strengthen those new connections."

Neuroligin is a member of a family of four protein molecules that bind to another family of proteins, the β-neurexins, across synapses. During the past decade, scientists have observed that neuroligin is critical for synapse formation and function, but it is only recently that a link between the two synapse-forming molecules and autism has been recognized, McAllister said.

Lead study author and UC Davis postdoctoral fellow Stephanie Barrow said that researchers had hypothesized that neuroligin could facilitate the recruitment of other proteins important in building synapses, but no one had been able to directly visualize the process. That's because synapses are less than 1 micron wide 100 times narrower than a strand of human hair. To view the process, the researchers cultured neurons taken from newly born rats and flourescently labled the proteins neuroligin, PSD-95 and NMDA which are critical to synapse formation.

"We are the first to observe that neuroligin zips around dendrites (the branched projections of neurons) before synapses form and can accumulate very soon after contact between cells," Barrow said.

Barrow described what the team was able to visualize:

"Axons of one neuron grow toward the dendrites of neighboring neurons. As they do so, finger-like structures called filopodia extend and retract rapidly from the tip of the axons and eventually make a stable contact with the dendrite. We can then see neuroligin accumulate at these new contact sites very rapidly, possibly stabilizing adhesion between the two cells. After a few minutes, more neuroligin accumulates at this contact site, bringing NMDA receptors in with it, which is then followed by a much slower recruitment of PSD-95."

The images that accompany the study show that, indeed, the two synaptic receptor proteins, PSD-95 and NMDA, are independently recruited to the site of synapse formation once the connections are locked in place by neuroligin.

"Synapses are basically specialized sites of cell adhesion that are initially formed during development of the nervous system. Formation of viable synapses is crucial for establishing neuronal circuits that underlie behavior and cognition," said study senior author Philip Washbourne, a UC Davis postdoctoral fellow when the study was initiated and now an assistant professor of biology at the University of Oregon.

McAllister and Barrow are continuing to capture images of the dynamics of other important molecules during synapse formation. Their goal is to create a virtual cinematic representation that includes many of the molecules that play important roles in the formation of a normal, working synapse.

"Many people think that improper synapse formation leads to the symptoms of autism," McAllister said. "This research will allow us to learn more about how synapses form to better understand what aspects of synapse formation might be altered in the disorder."


'/>"/>

Contact: Phyllis Brown
phyllis.brown@ucdmc.ucdavis.edu
916-734-9023
University of California - Davis - Health System
Source:Eurekalert

Related biology news :

1. UC Davis begins $2.8 million in studies of agricultural nitrogens impacts
2. UC Davis bioengineer receives Hartwell Foundation grant to address skull fusion disorder of infants
3. UC Davis launches One Health care for wild mountain gorillas and human neighbors
4. UC Davis researchers identify a protein that may help breast cancer spread, beat cancer drugs
5. UC Davis bench-to-bedside research: Promising treatment in clinical trials
6. UC Davis research shows that newly discovered drug reduces heart enlargement
7. UC Davis researchers find molecule that targets brain tumors
8. UC Davis discovery offers hope for treating kidney cancer
9. UC Davis team refines cancer treatments to reduce potential nerve damage
10. UC Davis researchers exploring gene therapy to fight AIDS
11. UC Davis researchers discover Achilles heel in pancreatic cancer
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/8/2016)... , Dec. 8, 2016  Singulex, Inc., the ... Counting technology, entered into a license and supply agreement ... science. The agreement provides Singulex access to Thermo Scientific ... Europe is used to diagnose systemic bacterial ... States to aid in assessing the risk ...
(Date:12/7/2016)... , Dec. 7, 2016   Avanade ... successful Formula One teams in history, exploit biometric data ... stop performance and maintain the competitive edge against their ... 2016. Avanade has worked with Williams ... range of biometric data (heart rate, breathing rate, temperature ...
(Date:12/6/2016)... Valencell , the leading innovator in performance biometric ... consecutive year of triple digit growth for its PerformTek ... 360 percent increase in companies who have acquired Valencell ... sales of its wrist and ear Benchmark™ sensor systems, ... hearables for fitness and healthcare applications. ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... December 8, 2016 ... Molekulargenetik, erweitert seine Palette an anpassbaren SureSeq™ NGS-Panels ... FH Panels, das ein schnelles und kostengünstiges Studium ... Panel bietet eine Erkennung von Einzel-Nukleotid-Variationen (Single Nucleotide ... einem einzigen kleinen Panel und ermöglicht eine individuelle ...
(Date:12/8/2016)... -- Anaconda BioMed S.L., a pre-clinical stage medical device company ... system for the treatment of Acute Ischemic Stroke (AIS), ... join its Scientific Advisory Board (SAB). The SAB is ... and clinical experts to Anaconda BioMed S.L., as the ... to its clinical phase. The SAB is also ...
(Date:12/8/2016)... , ... December 08, 2016 ... ... the commercial launch of flexible packaging for their exceptionally efficient human mesenchymal ... system extends RoosterBio’s portfolio of bioprocess media products engineered to radically streamline ...
(Date:12/8/2016)... ... 08, 2016 , ... This CAST literature review and report looks at problems ... on the economic effects in countries that are major global commodity exporters and importers, ... resultant risk of low level presence (LLP) puts large volumes of trade worth billions ...
Breaking Biology Technology: