Two items relevant to long COVID

One of the tricky issues in studying in long COVID is: how widely do researchers cast their net? Initial reports acknowledged that people who were hospitalized and in intensive care may take a while to get back on their feet. But the number of people who had SARS-CoV-2 infections and were NOT hospitalized, yet experienced lingering symptoms, may be greater. A recent report from the United Kingdom, published in PLOS Medicine, studied more than Read more

All your environmental chemicals belong in the exposome

Emory team wanted to develop a standard low-volume approach that would avoid multiple processing steps, which can lead to loss of material, variable recovery, and the potential for Read more

Signature of success for an HIV vaccine?

Efforts to produce a vaccine against HIV/AIDS have been sustained for more than a decade by a single, modest success: the RV144 clinical trial in Thailand, whose results were reported in 2009. Now Emory, Harvard and Case Western Reserve scientists have identified a gene activity signature that may explain why the vaccine regimen in the RV144 study was protective in some individuals, while other HIV vaccine studies were not successful. The researchers think that this signature, Read more

dendritic spines

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 by Quinn Eastman in Neuro Leave a comment