Odorant-binding protein

Odorant-binding proteins (OBPs) are small (10 to 30 kDa) soluble proteins secreted by auxiliary cells surrounding olfactory receptor neurons, including the nasal mucus of many vertebrate species and in the sensillar lymph of chemosensory sensilla of insects. OBPs are characterized by a specific protein domain that comprises six α-helices joined by three disulfide bonds. Although the function of the OBPs as a whole is not well established, it is believed that they act as odorant transporters, delivering the odorant molecules to olfactory receptors in the cell membrane of sensory neurons.

The olfactory receptors of terrestrial animals exist in an aqueous environment, yet detect odorants that are primarily hydrophobic.[1] The aqueous solubility of hydrophobic odorants is greatly enhanced via odorant-binding proteins, which exist in the extracellular fluid surrounding the odorant receptors.[1] This family is composed of pheromone binding proteins (PBP), which are male-specific and associate with pheromone-sensitive neurons and general-odorant-binding proteins (GOBP).

These proteins were initially identified on the basis of their ability to bind with moderate-affinity radioactively labeled odorants.[2][3]

  1. ^ a b Vogt, R. G.; Prestwich, G. D.; Lerner, M. R. (January 1991). "Odorant-binding-protein subfamilies associate with distinct classes of olfactory receptor neurons in insects". Journal of Neurobiology. 22 (1): 74–84. doi:10.1002/neu.480220108. ISSN 0022-3034. PMID 2010751.
  2. ^ Pelosi, P.; Baldaccini, N. E.; Pisanelli, A. M. (1982-01-01). "Identification of a specific olfactory receptor for 2-isobutyl-3-methoxypyrazine". The Biochemical Journal. 201 (1): 245–248. doi:10.1042/bj2010245. ISSN 0264-6021. PMC 1163633. PMID 7082286.
  3. ^ Shi, W.; Ostrov, D.A.; Gerchman, S.E.; Graziano, V.; Kycia, H.; Studier, B.; Almo, S.C.; Burley, S.K. (1999-08-25). "PNP Oxidase from Saccharomyces Cerevisiae". doi:10.2210/pdb1ci0/pdb. {{cite journal}}: Cite journal requires |journal= (help)