Pheromone-binding protein 1 (Bombyx mori) (BmorPBP1)

Pheromone-binding protein 1 from the silkworm moth Bombyx mori (BmorPBP1) is a specialized transport protein essential for insect olfaction. It is found in high concentrations within the sensillar lymph of the antennae, where it functions to solubilize and transport the hydrophobic sex pheromone, bombykol, to the olfactory receptors on the sensory neuron dendrites (UniProt P12964). The protein exhibits a sophisticated pH-dependent mechanism: at the neutral pH of the lymph, it binds the pheromone, but at the acidic pH near the neuronal membrane, the C-terminus forms an alpha-helix that enters the binding pocket, displacing the pheromone for receptor activation (Sandler et al., 2000). While not a target for human disease, BmorPBP1 is a primary model for studying insect chemical communication and serves as a template for developing insect repellents or attractants in agricultural applications (Leal, 2013). Its high specificity for bombykol makes it a key component in the sensitive detection of chemical signals in the environment. Understanding its structural dynamics allows researchers to design synthetic ligands that can interfere with moth mating behaviors, providing a basis for eco-friendly pest management strategies. The protein belongs to the larger family of odorant-binding proteins (OBPs), which are characterized by a conserved pattern of six cysteines forming three disulfide bonds. Research into BmorPBP1 has also explored its interaction with various pheromone analogs and environmental odors, highlighting its role as a selective filter in the insect's olfactory system.

Other names

PBP1Bombykol-binding proteinBmorPBP

BmorPBP1 facilitates the transport of hydrophobic pheromones through the aqueous sensillar lymph to olfactory receptors; it utilizes a pH-dependent conformational change where the C-terminus acts as an internal ligand to eject the pheromone at the acidic membrane surface (Sandler et al., 2000; Wojtasek and Leal, 1999).