1F35

CRYSTAL STRUCTURE OF MURINE OLFACTORY MARKER PROTEIN

Summary for 1F35

• Entry DOI: 10.2210/pdb1f35/pdb
• Descriptor: OLFACTORY MARKER PROTEIN, ZINC ION, CACODYLATE ION, ... (4 entities in total)
• Functional Keywords: beta, structural genomics, psi, protein structure initiative, northeast structural genomics consortium, nesg, signaling protein
• Biological source: Mus musculus (mouse)
• Cellular location: Cytoplasm : Q64288
• Total number of polymer chains: 2
• Total formula weight: 38774.63

Authors

Smith, P.C.,Hunt, J.F.,Northeast Structural Genomics Consortium (NESG) (deposition date: 2000-05-31, release date: 2001-08-15, Last modification date: 2024-10-30)

Primary citation

Smith, P.C.,Firestein, S.,Hunt, J.F.
The crystal structure of the olfactory marker protein at 2.3 A resolution.
J.Mol.Biol., 319:807-821, 2002

PubMed Abstract: Olfactory marker protein (OMP) is a highly expressed and phylogenetically conserved cytoplasmic protein of unknown function found almost exclusively in mature olfactory sensory neurons. Electrophysiological studies of olfactory epithelia in OMP knock-out mice show strongly retarded recovery following odorant stimulation leading to an impaired response to pulsed odor stimulation. Although these studies show that OMP is a modulator of the olfactory signal-transduction cascade, its biochemical role is not established. In order to facilitate further studies on the molecular function of OMP, its crystal structure has been determined at 2.3 A resolution using multiwavelength anomalous diffraction experiments on selenium-labeled protein. OMP is observed to form a modified beta-clamshell structure with eight antiparallel beta-strands. While OMP has no significant sequence homology to proteins of known structure, it has a similar fold to a domain found in a variety of existing structures, including in a large family of viral capsid proteins. The surface of OMP is mostly convex and lacking obvious small molecule binding sites, suggesting that it is more likely to be involved in modulating protein-protein interaction than in interacting with small molecule ligands. Three highly conserved regions have been identified as leading candidates for protein-protein interaction sites in OMP. One of these sites represents a loop known to mediate ligand interactions in the structurally homologous EphB2 receptor ligand-binding domain. This site is partially buried in the crystal structure but fully exposed in the NMR solution structure of OMP due to a change in the orientation of an alpha-helix that projects outward from the structurally invariant beta-clamshell core. Gating of this conformational change by molecular interactions in the signal-transduction cascade could be used to control access to OMP's equivalent of the EphB2 ligand-interaction loop, thereby allowing OMP to function as a molecular switch.

PubMed: 12054872
DOI: 10.1016/S0022-2836(02)00242-5

Experimental method

X-RAY DIFFRACTION (2.3 Å)