Structural and functional analyses explain Pea KAI2 receptor diversity and reveal stereoselective catalysis during signal perception

Guercio et al., combine structural biology, biochemistry, and plant biology to reveal the dual functions of evolutionarily diverged Pisum KAI2A and KAI2B as both receptors and enzymes with distinct ligand selectivity, and propose adaptive sensitivity to strigolactone phytohormones by KAI2B. They reported the structures of KAI2 in apo and ligand intermediate -bound states that further illuminate KAI2s catalysis mechanism.