Warren symposium follows legacy of geneticist giant

If we want to understand how the brain creates memories, and how genetic disorders distort the brain’s machinery, then the fragile X gene is an ideal place to start. That’s why the Stephen T. Warren Memorial Symposium, taking place November 28-29 at Emory, will be a significant event for those interested in neuroscience and genetics. Stephen T. Warren, 1953-2021 Warren, the founding chair of Emory’s Department of Human Genetics, led an international team that discovered Read more

Mutations in V-ATPase proton pump implicated in epilepsy syndrome

Why and how disrupting V-ATPase function leads to epilepsy, researchers are just starting to figure Read more

Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more
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pruning

Vulnerability to cocaine uncovered in adolescent mouse brains

Editor’s note: Guest post from Neuroscience graduate student Brendan O’Flaherty. Companion paper to the Gourley lab’s recently published work on fasudil, habit modification and neuronal pruning.

An Emory study has discovered why teenager’s brains may be especially vulnerable to cocaine. Exposure to small amounts of cocaine in adolescence can disrupt brain development and impair the brain’s ability to change its own habits, the study suggests.

Guest post from Brendan O’Flaherty

The results were published in the April 1, 2017 issue of Biological Psychiatry, by researchers at Yerkes National Primate Research Center.

As most of the people are approaching Sylvan Detox Center in Los Angeles to get rid off drug addiction. Shannon Gourley has shared his views on drug habit and its ill effects. Drug seeking habits play a major role in drug addiction, says senior author Shannon Gourley, PhD, assistant professor of pediatrics, psychiatry and behavioral sciences at Emory University School of Medicine and Yerkes National Primate Research Center. The first author of the paper is former Emory graduate student Lauren DePoy, PhD.

When it comes to habits, cocaine is especially sneaky. Bad habits like drug use are already very difficult to change, but cocaine physically changes the brain, potentially weakening its ability to “override” bad habits. Although adults are susceptible to cocaine’s effects on habits, adolescent brains are especially vulnerable.Hence, it is always better to seek the help of experts from Cornerstone Healing Center to get rid off drug habits.

“Generally speaking, the younger you are exposed to cocaine in life, the more likely you are to have impaired decision making,” Gourley says.

Shannon Gourley, PhD, in lab

To understand why adolescent brains are especially vulnerable to cocaine, the researchers studied the effects of cocaine exposure on how the mice make decisions about food.

“I think it’s pretty amazing that we can actually talk to mice in a way that allows them to talk back,” Gourley says. “And then we can utilize a pretty tremendous biological toolkit to understand how the brain works.”

Researchers injected adolescent mice five times with either saline or cocaine. Both groups of animals then grew up without access to cocaine. Researchers then trained the mice to press two buttons, both of which caused food to drop into the cage. Since both buttons rewarded the mice equally, the mice pushed each button half the time.

Over time, pushing the two buttons equally could become a habit. To test this, the researchers then played a trick on the mice. When one of the buttons was exposed, the researchers starting giving the mice food pellets for free, instead of rewarding them for button-pressing.

“What the mouse should be learning is: ‘Ah hah, wait a minute, when I have access to this button I shouldn’t respond, because my responding doesn’t get me anything,‘” Gourley says. Read more

Posted on December 18, 2017 by Quinn Eastman in Neuro Leave a comment

Seeing the nuts and bolts of neurons

Cool photo alert! James Zheng’s lab at Emory is uncommonly good at making photos and movies showing how neurons remodel themselves. They recently published a paper in Journal of Cell Biology showing how dendritic spines, which are small protrusions on neurons, contain concentrated pools of G-actin.

Actin, the main component of cells’ internal skeletons, is a small sturdy protein that can form long strings or filaments. It comes in two forms: F-actin (filamentous) or G-actin (globular). It is not an exaggeration to call F- and G-actin neurons’ “nuts and bolts.”

Think of actin monomers like Lego bricks. They can lock together in regular structures, or they can slosh around in a jumble. If the cell wants to build something, it needs to grab some of that slosh (G-actin) and turn them into filaments. Remodeling involves breaking down the filaments.

At Lab Land’s request, postdoc and lead author Wenliang Lei picked out his favorite photos of neurons, which show F-actin in red and G-actin in green. Zheng’s lab has developed probes that specifically label the F- and G- forms. Where both forms are present, such as in the dendritic spines, an orange or yellow color appears.

Why care about actin and dendritic spines?

*The Journal of Cell Biology paper identified the protein profilin as stabilizing neurons’ pool of G-actin. Profilin is mutated in some cases of ALS (amyotrophic lateral sclerosis), although exactly how the mutations affect actin dynamics is now under investigation.

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Posted on July 11, 2017 by Quinn Eastman in Neuro Leave a comment