Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lens fiber proteins with apparent molecular weights 57,000, 70,000, 82,000, and 100,000 were components in urea insoluble, membrane-rich fractions. Monoclonal antibodies against these proteins labeled membranes by immunofluorescence microscopy of sheep lens cryosections and are thus referred to as membrane proteins MP57, MP70, MP82, and MP100. MP70 has previously been localized in fiber junctional membranes (Kistler et al 1985, J Cell Biol 101:28-35). Using radioimmunoassays, the authors found a different membrane protein composition for the cortical and nuclear sheep lens regions. In addition, the membrane protein composition altered with the overall lens age. All the above membrane antigens were eventually cleaved by proteolysis in older fibers, and their degradation patterns could be grouped into distinct classes. The results are of basic importance for cataract research.
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PMID:Aging of lens fibers. Mapping membrane proteins with monoclonal antibodies. 370 26

Four genes encoding eye lens-specific proteins, potential candidate genes for congenital cataract (CC) mutations, were mapped in the mouse genome using a panel of somatic cell hybrids and DNAs from the EU-CIB (European Collaborative Interspecific Backcross). Two of them are lens fiber cell structural proteins: the Cryba1 locus encoding crystallinbetaA3/A1 maps to chromosome 11, 2.5 +/- 2.5 cM distal to D11Mit31, and the Crybb2 locus encoding crystallinbetaB2 maps to chromosome 5, 9.1 +/- 4.3 cM distal to D5Mit88. The other two genes encode lens-specific gap junction and integral membrane proteins, respectively: The Gja8 locus encoding gap juction membrane channel protein alpha8, also called connexin50 or MP70, maps to chromosome 3, 11.9 +/- 5.0 cM distal to D3Mit22, and the Lim2 locus encoding lens intrinsic membrane protein 2, also called MP19, maps to chromosome 7, 2.5 +/- 2.5 cM proximal to Ngfg. All four map positions, when compared with the corresponding positions in human, lie within known regions of conserved synteny between mouse and human chromosomes.
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PMID:Mapping of four mouse genes encoding eye lens-specific structural, gap junction, and integral membrane proteins: Cryba1 (crystallin beta A3/A1), Crybb2 (crystallin beta B2), Gja8 (MP70), and Lim2 (MP19). 866 93

A missense mutation in one of the three lens connexins, alpha8-connexin, has been recently shown to be the genetic basis of the zonular pulverant lens cataract. This connexin had been considered to be expressed only in lens fibre cells. The present studies show that alpha8-connexin is also expressed in the lens epithelial cell layer. For this study, the distribution of gap junctions in the adult bovine lens has been investigated by confocal immunofluorescence microscopy using antibodies against alpha8-connexin (MP70) and alpha1-connexin (Cx43). In addition to the anticipated localisation of alpha8-connexin to the broad faces of lens fibre cells as reported in other species, alpha8-connexin was also found colocalized with alpha1-connexin at plaques in the lateral epithelial-epithelial plasma membranes of the bovine lens. These data suggest that mixed alpha8-connexin/alpha1-connexin plaques are between epithelial cells at their apico-lateral plasma membranes, rather than between epithelial and fibre cells. Indeed, freeze fracture analyses of the epithelial-fibre cell interface failed to reveal gap junctions connecting the epithelium and the underlying fibre cells. Importantly, microdissection and subsequent immunoblotting of lens epithelium samples confirmed the immunolocalisation results. The data suggest mature mammalian lens epithelial cells could form either heteromeric, heterotypic and/or mixed homomeric-homotypic gap junctional complexes with unique physiological properties, an important point when considering the role of epithelial cell connexins in cataractogenesis.
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PMID:Gap junctions containing alpha8-connexin (MP70) in the adult mammalian lens epithelium suggests a re-evaluation of its role in the lens. 1037 48