How Animal Cells Use 'Disomes' to Survive Starvation and Stress

Scientists have discovered how animal cells safeguard their protein production machinery during stress. A new study shows that ribosomes—the cellular structures responsible for protein synthesis—form inactive pairs called 'disomes' when nutrients are scarce. This finding, led by Erin Schuman at the Max Planck Institute, sheds light on how animal cells, including neurons, conserve energy in harsh conditions.

The research team used cryo-electron tomography to observe ribosome pairs inside frozen, intact animal cells for the first time. Unlike previous methods, this technique allowed them to see how ribosomes connect in their natural state. The key finding was that RNA 'tentacles,' specifically a segment called 'expansion segment 31b,' form a 'kissing loop' to link two ribosomes together.

These linked ribosomes, or 'disomes,' act as a protective storage system. When animal cells face starvation, they temporarily shut down protein production by pairing ribosomes. Once conditions improve, the pairs quickly separate, allowing normal function to resume. The study combined cell biology, biochemistry, and genetic experiments in yeast and mammalian cells to confirm this mechanism in the animal kingdom.

The process appears unique to animal cells and may explain how neurons survive prolonged stress. By targeting RNA interactions like the 'kissing loop,' future therapies could help treat neurological disorders where protein production is disrupted.

This breakthrough highlights a new way animal cells manage stress by reorganizing their ribosomes. The findings open doors for medical research, particularly in diseases linked to faulty protein synthesis. Understanding how disomes form and dissolve could lead to treatments that improve neuronal resilience during nutrient shortages in the animal kingdom.