A long-standing mystery of ENOD40, a pioneering gene in legume nodulation research, has been solved. ENOD40 acts as a natural microRNA sponge to regulate the legume nodulation pathway, enabling nitrogen-fixing nodule formation. The discovery sheds light on a new layer of control in plant-microbe symbiotic relationships.
Researchers at the University of Cambridge have discovered that the plant hormone gibberellin is essential for legume nitrogen-fixing root nodule formation and maturation. The study used a highly sensitive next-generation biosensor to visualize GA accumulation in specific zones of the root, revealing its critical role in nodulation.
Legume plants have a unique ability to interact with nitrogen-fixing bacteria, allowing them to thrive without external nitrogen. Researchers identified four essential phosphorylation sites on the SYMRK kinase that mediate this symbiotic relationship.
Salt stress alters legume responses to symbiotic rhizobacteria by modulating gene expression. Several genes with well-characterized functions in nodulation are highly induced under salt stress, making the plant hypersensitive to bacterial signals.