Structural basis of pheromone binding to mouse major urinary protein (MUP‐I)

Abstract
The mouse major urinary proteins are pheromone‐binding proteins that function as carriers of volatile effectors of mouse physiology and behavior. Crystal structures of recombinant mouse major urinary protein‐I (MUP‐I) complexed with the synthetic pheromones, 2‐sec‐butyl‐4,5‐dihydrothiazole and 6‐hydroxy‐6‐methyl‐3‐heptanone, have been determined at high resolution. The purification of MUP‐I from mouse liver and a high‐resolution structure of the natural isolate are also reported. These results show the binding of 6‐hydroxy‐6‐methyl‐3‐heptanone to MUP‐I, unambiguously define ligand orientations for two pheromones within the MUP‐I binding site, and suggest how different chemical classes of pheromones can be accommodated within the MUP‐I β‐barrel.