Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

B4-2-1 cells (Lec15 cells) are Chinese hamster ovary cells deficient in mannosylphosphoryldolichol synthase activity. They synthesize the truncated lipid intermediate Man5GlcNAc2-P-P-dolichol rather than the Glc3Man9GlcNAc2-P-P-dolichol synthesized by wild-type cells. In this report we present evidence that these cells did synthesize glucosylated Man5GlcNAc2-P-P-dolichol, but this species represented only a minor fraction of the labeled oligosaccharide-lipid. On the other hand, glucosylated oligosaccharides were a major species transferred to protein in these cells, showing that in vivo, glucosylated oligosaccharides are preferentially transferred to protein. The truncated oligosaccharides found in B4-2-1 cells were removed from the protein by N-glycanase treatment, since they were resistant to both endo-beta-N-acetylglucosaminidase H and F activity. B4-2-1 cells processed the glucosylated, truncated oligosaccharides transferred to G protein of vesicular stomatitis virus, leading to infectious virus.
 ...
PMID:Lec15 cells transfer glucosylated oligosaccharides to protein. 144 60

The conformational epitopes reactive with neutralizing monoclonal antibodies (MAbs) appear to be clustered at the middle third of the glycoprotein (G) of the New Jersey serotype of vesicular stomatitis virus (VSV-NJ) and are flanked by two N-linked carbohydrate chains (W. Keil and R.R. Wagner, Virology 170, 392-407, 1989). We report here studies on the effect of glycosylation on the reactivity of VSV-NJ G protein derived from released virions or immunoprecipitated from pulse-labeled cells was not significantly affected in its reactivity with MAbs directed to epitope IV mapped toward the amino-terminus, nor to the centrally located conformational epitopes VI, VIII, and IX. However, there was a 5- to 15-fold decrease in the reactivity with MAb of epitopes VI, VIII, and IX on unglycosylated G protein either isolated from a ribosome-enriched membrane fraction or immunoprecipitated from whole VSV-infected cells labeled for 15 hr in the presence of tunicamycin. In sharp contrast, epitope V and to a somewhat lesser extent epitope VII exhibited decreased reactivity with their respective MAbs when unglycosylated G protein was isolated from released viral particles or from pulse-labeled cells infected with VSV-NJ in the presence of tunicamycin. Enzymatic removal of preformed carbohydrate chains with N-glycanase had little or no effect on the MAb-reactivity of epitopes V and VII, indicating that the carbohydrate chains per se do not influence the antigenic specificity of VSV-NJ G protein. These data suggest that the formation of N-linked carbohydrate chains influences the structure of the VSV-NJ G protein in such a way that epitopes V and VII are shielded from reactivity with their specific MAbs from an early stage of G-protein processing and to a much lesser extent epitopes VI, VIII, and IX at late stages of intracellular processing. These results are compatible with, but do not prove, the hypothesis that N-linked glycosylation plays a key role in promoting the formation and the stability of the disulfide bonds that determine the epitope-specific conformational integrity of the VSV-NJ glycoprotein.
 ...
PMID:Effect of glycosylation on the conformational epitopes of the glycoprotein of vesicular stomatitis virus (New Jersey serotype). 170 43