Figure 1. Structures of a fluorescence reporter and a mosquito oviposition pheromone.

N-phenyl-1-naphthylamine (NPN) is widely used in binding assays with insect OBPs. (5 R,6 S)-6-acetoxy-5-hexadecanolide (MOP) is an attractant first isolated from eggs of Cx. quinquefasciatus ³⁷, but it is known to bind not only to CquiOBP1, but also to its orthologous proteins, i.e., AaegOBP1 and AgamOBP1 ¹⁹.