Novel proteinaceous infectious particles cause scrapie.

@article{Prusiner1982NovelPI,
  title={Novel proteinaceous infectious particles cause scrapie.},
  author={Stanley B. Prusiner},
  journal={Science},
  year={1982},
  volume={216 4542},
  pages={
          136-44
        }
}
After infection and a prolonged incubation period, the scrapie agent causes a degenerative disease of the central nervous system in sheep and goats. Six lines of evidence including sensitivity to proteases demonstrate that this agent contains a protein that is required for infectivity. Although the scrapie agent is irreversibly inactivated by alkali, five procedures with more specificity for modifying nucleic acids failed to cause inactivation. The agent shows heterogeneity with respect to size… 

Scrapie: the disease and the infectious agent

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  • 1982
TLDR
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TLDR
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TLDR
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  • Biology
    FEMS microbiology immunology
  • 1992
TLDR
A modified form of the membrane hypothesis could account for immunological as well as genetic aspects of these diseases.

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    Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine
  • 1996
TLDR
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  • R. Rohwer
  • Biology
    Current topics in microbiology and immunology
  • 1991
TLDR
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A modified host protein model of scrapie.

TLDR
The scrapie agent is still not completely characterized biochemically and ultrastructurally, but its requirement for a functional protein has been established and a model in which Sp33-37, a modified host protein, is the critical component of the scrapieAgent is proposed.
...

References

SHOWING 1-10 OF 109 REFERENCES

Scrapie agent contains a hydrophobic protein.

TLDR
Employing preparations of the scrapie agent enriched 100- to 1000-fold with respect to protein, it was found that digestion by proteinase K destroyed more than 99.9% of the infectivity, providing good evidence for a protein and for hydrophobic domains within the scrapIE agent.

Evidence for the low molecular weight nature of scrapie agent

TLDR
The data presented here describe a purification procedure resulting in scrapie infectivity which migrates during polyacrylamide gel electrophoresis as a defined area of infectivity in a region characteristic of low molecular weight nucleic acid.

Evidence for an essential DNA component in the Scrapie agent

ONE of the enigmas of microbiology has been the nature of the aetiological agent causing scrapie disease in sheep and goats. The unusual resistance of infectivity to heat, formaldehyde, nucleases and

Is the scrapie agent a virus?

TLDR
The present experiments were designed to determine if similar 14-nm virus-like particles could be isolated from hamster brains infected with scrapie agent and, if so, if the 14- nm virus- like particles induce scrapie in mice and hamsters.

Reversible chemical modification of the scrapie agent.

TLDR
Chemical modification of the scrapie agent by diethyl pyrocarbonate reduced the titer 1000-fold and exposure of the inactivated agent to hydroxylamine resulted in complete restoration of infectivity.

Molecular properties, partial purification, and assay by incubation period measurements of the hamster scrapie agent.

TLDR
Measurements of incubation period length were related to the titer of the agent and the dilution of the inoculated sample, providing evidence in support of a protein component within the scrapie agent which is essential for maintenance of infectivity.

Some Properties of the Scrapie Agent and Its Behavior in Mice

TLDR
The long incubation period, the slowly progressive course of the disease, and the degenerative changes in the central nervous system all are consistent with the view that the agent under study is the transmissible agent of scrapie.

Scrapie: A transmissible and hereditary disease of sheep

TLDR
Recent work has shown that there are specific degenerative changes in the brain in the hypothalamic-hypophyseal system and in the olivo-ponto-cerebellar system and that scrapie is not naturally infectious.

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TLDR
It is suggested that scrapie can best be considered to arise from a replicable change in the structural pattern of a commonly occurring unit membrane and three possible mechanisms for its self-replication are proposed.

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TLDR
Subcellular fractionation of scrapie-infected hamster brain indicated the association of the scrapie agent with a component of the endomembrane system and DNA polymerase activity demonstrated a direct correlation with regions of scrapIE activity from the gradient fractions.
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