L-Arginine Stabilizes Protein Droplets and Prevents Harmful Fibril Formation

A naturally occurring molecule already present in human cells has been shown to stabilize protein droplets and prevent their conversion into harmful amyloid fibrils linked to neurodegenerative diseases such as Alzheimer’s, according to new research from the University at Buffalo.

The study, published in Nature Communications, found that the metabolite L-arginine enhances the stability of liquid-like protein droplets formed by tau protein, protecting them from transitioning into solid-like clumps known as fibrils. These fibrils disrupt normal cellular functions, including the stabilization of microtubules that help transport materials within neurons.

“Healthy cells might already be using small molecules like L-arginine to stabilize functional droplets and prevent them from conversion to toxic assemblies,” said Priya R. Banerjee, professor of physics at the University at Buffalo College of Arts and Sciences and lead researcher on the study.

The research demonstrates that L-arginine does not interfere with the physiological functions of protein droplets but instead supports their ability to assemble and maintain microtubule stability, which is essential for intracellular transport in nerve cells.