Ancestral motif enables broad DNA binding by NIN, a master regulator of rhizobial symbiosis

Researchers at University of Tsukuba have uncovered a master transcriptional regulator that controls rhizobial symbiosis between plants and nitrogen-fixing bacteria. By identifying an amino acid motif that emerged before the appearance of rhizobial symbiosis, they show that stabilization of DNA binding enabled this regulator to control a wide array of genes involved in nodule formation, bacterial infection, and symbiotic nitrogen fixation.