AI Reveals a New Cellular “Off Switch” Linked to Cancer Pathways

Summary

Cornell researchers used AlphaFold, an AI system for predicting protein structures and interactions, to search for unknown partners of Arf1, a protein that directs the movement of cellular cargo. The system quickly produced candidates for laboratory testing, including Avl9, a poorly understood protein previously associated with secretion and cancer-cell movement. Experiments showed that Avl9 turns Arf1 off after Arf1 has completed its role in intracellular transport. Testing normal and mutated Avl9 found that a single amino-acid change eliminated this regulatory activity; in human lung cancer cells, the change also reduced cell movement. The results challenge the previous view that DENN-domain proteins mainly function as molecular “on switches.” At least one related human protein showed similar behavior, suggesting that some members of this protein family form a broader system for balancing cellular transport. Because disruptions in transport and cell movement can affect tumor growth and spread, the findings may help researchers study disease-related mechanisms, although the article does not establish a cancer treatment. Published in the Journal of Cell Biology, the study illustrates how AI can narrow the search for biologically testable questions before detailed experiments.