Team from the Spanish National Center for Cancer Research (CNIO) has discovered a molecular switch that controls the ability of organisms to adapt to low levels of cellular nutrients.

Getting energy and nutrients from the environment – eating is one of the most important functions of the body. It has been regulated by complex mechanisms for hundreds of millions of years. Scientists are explaining some of them only now.

In a recent study, scientists discovered one of their key components of such a mechanism – a switch that controls the ability of organisms to adapt to low levels of cellular nutrients.

Experiments in mice have shown that the RagA protein works as a sensor for nutrient levels in the cell. RagA in GTP-bound state mediates the triggering of the mTOR signaling pathway, which leads to increased nutrient consumption. Mice with permanently activated RagA had metabolic disorders, and in particular, they could not adapt to hunger.

During the study, the scientists also prevented RagA from shutting down, but only partially so that the mice could survive. As a result, they showed metabolic changes, including homeostasis of glucose, amino acids, ketones, and lipids.

The molecular pathway of RagA is as important as other nutrients that play a key role in nutrition, such as insulin. However, RagA has been identified not so long ago, and relatively little is known about its role in the regulation of metabolism. Understanding how Rag proteins work in the cell will help to find new strategies to combat obesity and disease associated with this disease.

The research is published in Nature Communications.