Molecule may help maintain brain's synaptic balance

June 13, 2017
Fruit fly brain labeled in different colors using the Brainbow method that allows researchers to distinguish one neuron from another. Credit: Timothy Mosca

Many neurological diseases are malfunctions of synapses, or the points of contact between neurons that allow senses and other information to pass from finger to brain. In the brain, there is a careful balance between the excitatory synapses that allow messages to pass, and the inhibitory synapses that dampen the signal. When that balance is off, the brain becomes unable to process information normally, leading to conditions like epilepsy.

Now researchers at Jefferson have discovered a molecule that may play a role in helping maintain the balance of excitatory and . The results were published in the journal eLife, a project of the Howard Hughes Medical Institute, the Wellcome Trust and the Max Planck Institute.

Timothy Mosca, Ph.D., Assistant Professor in the Department of Neuroscience at the Vickie and Jack Farber Institute for Neuroscience of Thomas Jefferson University, discovered that a molecule called LRP4, was important in creating excitatory synapses—the ones that keep a message passing from one neuron to the next. When the researchers knocked out the LRP4 gene in fruit flies, they saw a 40 percent loss of excitatory synaptic connections in the brain, but no such loss of , suggesting that the molecule was specific to one kind of synapse.

The researchers used a new technology called expansion microscopy to get a better view of the fruit fly . "In most cases, if you want to see very small things with better resolution, you get a better microscope," says Mosca. "The other option is to make the small things bigger." By infusing the neurons they were studying with the chemical in diapers that swells as it absorbs water, they were able to make the neurons and their synapses enlarged enough to see them more clearly.

"Most involved in synapse biology are vital to both excitatory and inhibitory neurons," says Mosca. "The idea that we now have a molecule that appears to be specific to suggests there is probably a parallel molecule that exists that helps form inhibitory ones, that we just haven't found yet."

A better understanding of the unique biology of excitatory and inhibitory may go a long way in helping researchers untangle the many diseases that are thought to be related to synapse dysfunction such as epilepsy, but also autism and schizophrenia.

Explore further: Visualization of newly formed synapses with unprecedented resolution

More information: Timothy J Mosca et al, Presynaptic LRP4 promotes synapse number and function of excitatory CNS neurons, eLife (2017). DOI: 10.7554/eLife.27347

Related Stories

Visualization of newly formed synapses with unprecedented resolution

August 11, 2016
The formation of excitatory and inhibitory synapses between neurons during early development gives rise to the neuronal networks that enable sensory and cognitive functions in humans. Inhibitory synapses decrease the likelihood ...

Brain connections are more sophisticated than thought

September 8, 2016
In 1959, a scientist named Edward Gray showed that the miniscule gaps between neurons where chemical messages are sent, called synapses, come in two main varieties, which researchers later dubbed "excitatory" and "inhibitory."

Bipolar disorder candidate gene, validated in mouse experiment

February 15, 2017
A team of researchers, affiliated with UNIST has made a significant breakthrough in the search for the potential root causes of bipolar disorder.

Blame it on the astrocytes

July 11, 2014
In the brains of all vertebrates, information is transmitted through synapses, a mechanism that allows an electric or chemical signal to be passed from one brain cell to another. Chemical synapses, which are the most abundant ...

Protein family linked to autism suppresses the development of inhibitory synapses

January 28, 2013
Synapse development is promoted by a variety of cell adhesion molecules that connect neurons and organize synaptic proteins. Many of these adhesion molecules are linked to neurodevelopmental disorders; mutations in neuroligin ...

Scientists find sensor that makes synapses fast

January 17, 2017
Synapses, the connections between neurons, come in different flavors, depending on the chemical they use as transmitter. Signal transmitters, or neurotransmitters, are released at the synapse after calcium ions flow into ...

Recommended for you

Research reveals 'exquisite selectivity' of neuronal wiring in the cerebral cortex

August 21, 2017
The brain's astonishing anatomical complexity has been appreciated for over 100 years, when pioneers first trained microscopes on the profusion of branching structures that connect individual neurons. Even in the tiniest ...

Afternoon slump in reward response

August 21, 2017
Activation of a reward-processing brain region peaks in the morning and evening and dips at 2 p.m., finds a study of healthy young men published in The Journal of Neuroscience. This finding may parallel the drop in alertness ...

Researchers find monkey brain structure that decides if viewed objects are new or unidentified

August 18, 2017
A team of researchers working at the University of Tokyo School of Medicine has found what they believe is the part of the monkey brain that decides if something that is being viewed is recognizable. In their paper published ...

Artificial neural networks decode brain activity during performed and imagined movements

August 18, 2017
Artificial intelligence has far outpaced human intelligence in certain tasks. Several groups from the Freiburg excellence cluster BrainLinks-BrainTools led by neuroscientist private lecturer Dr. Tonio Ball are showing how ...

How whip-like cell appendages promote bodily fluid flow

August 18, 2017
Researchers at Nagoya University have identified a molecule that enables cell appendages called cilia to beat in a coordinated way to drive the flow of fluid around the brain; this prevents the accumulation of this fluid, ...

Researchers make surprising discovery about how neurons talk to each other

August 17, 2017
Researchers at the University of Pittsburgh have uncovered the mechanism by which neurons keep up with the demands of repeatedly sending signals to other neurons. The new findings, made in fruit flies and mice, challenge ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.