In:
Journal of Neurochemistry, Wiley, Vol. 90, No. 1 ( 2004-07), p. 102-116
Abstract:
Olfactory marker protein (OMP) participates in the olfactory signal transduction pathway. This is evident from the behavioral and electrophysiological deficits of OMP‐null mice, which can be reversed by intranasal infection of olfactory sensory neurons with an OMP‐expressing adenovirus. Bex, b rain e xpressed X ‐linked protein, has been identified as a protein that interacts with OMP. We have now further characterized the interaction of OMP and Bex1/2 by in vitro binding assays and by immuno‐coprecipitation experiments. OMP is a 19 kDa protein but these immunoprecipitation studies have revealed the unexpected presence of a 38 kDa band in addition to the expected 19 kDa band. Furthermore, the 38 kDa form was preferentially co‐immunoprecipitated with Bex from cell extracts. In‐gel tryptic digestion, mass spectrometry, and two‐dimensional gel electrophoresis indicate that the 38 kDa protein behaves as a covalently cross‐linked OMP‐homodimer. The 38 kDa band was also identified in western blots of olfactory epithelium demonstrating its presence in vivo . The stabilities and subcellular localizations of the OMP‐monomer and ‐dimer were studied in transfected cells. These results demonstrated that the OMP‐dimer is much less stable than the monomer, and that while the monomer is present both in the nuclear and cytosolic compartments, the dimer is preferentially located in a Triton X‐100 insoluble cytoskeletal fraction. These novel observations led us to hypothesize that regulation of the level of the rapidly turning‐over OMP‐dimer and its interaction with Bex1/2 is critical for OMP function in sensory transduction.
Type of Medium:
Online Resource
ISSN:
0022-3042
,
1471-4159
DOI:
10.1111/jnc.2004.90.issue-1
DOI:
10.1111/j.1471-4159.2004.02463.x
Language:
English
Publisher:
Wiley
Publication Date:
2004
detail.hit.zdb_id:
2020528-4
SSG:
12
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