Abstract:
:A highly purified fraction obtained from scrapie (263-K strain)-infected hamsters' brains by an alternative procedure without proteinase K treatment contained a protease-resistant form of the scrapie precursor protein (PrPSc) and infectivity of 9.9 +/- 0.7 log LD50/ml. Polyclonal antibodies produced against hamster scrapie amyloid protein (PrP27-30) and used in a neutralization test diminished infectivity of the PrPSc preparations by 1.6 log after intracerebral inoculation and by 1 log after intraperitoneal inoculation. PrPSc was subjected to size-exclusion HPLC; greater than or equal to 60% of the eluted infectious units were recovered from the peak with an apparent mass of 30.4 +/- 0.6 kDa. Characterization by UV absorption spectra, SDS/PAGE, immunoblots, N-terminal amino acid sequence, and neutral sugar and amino sugar analyses demonstrated homogeneity of the infectious units. The neutral sugar and amino sugar compositional analyses revealed high mannose, glucosamine, fucose, and sialic acid content. This demonstrated an extensive posttranslational modification by the complex type of N-linked glycosylation and glycane core of C-terminal glycolipid of PrPSc. The results correspond to the predicted size, composition, and sequence of PrPSc and indicate that this protein may be the only component of scrapie infectious unit or the infectious form of scrapie precursor.
journal_name
Proc Natl Acad Sci U S Aauthors
Safar J,Wang W,Padgett MP,Ceroni M,Piccardo P,Zopf D,Gajdusek DC,Gibbs CJ Jrdoi
10.1073/pnas.87.16.6373subject
Has Abstractpub_date
1990-08-01 00:00:00pages
6373-7issue
16eissn
0027-8424issn
1091-6490journal_volume
87pub_type
杂志文章abstract::Widespread belief in misinformation circulating online is a critical challenge for modern societies. While research to date has focused on psychological and political antecedents to this phenomenon, few studies have explored the role of digital media literacy shortfalls. Using data from preregistered survey experiment...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1920498117
更新日期:2020-07-07 00:00:00
abstract::We have cloned and partially characterized 24 loci from the human genome which are complementary to U1, U2, or U3, the three major species of small nuclear RNA (snRNA) in HeLa cells. When compared to the known U1 (human) and U2 (rat) snRNA sequences, the DNA sequences we report here for the complementary regions from ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.2.810
更新日期:1981-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.73.12.4698
更新日期:1976-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.3.941
更新日期:1991-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.10.3509
更新日期:1985-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1615652114
更新日期:2017-05-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.25.14745
更新日期:1998-12-08 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.6.1860
更新日期:1985-03-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.16.7327
更新日期:1995-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0608556103
更新日期:2006-11-21 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.6.2023
更新日期:1982-03-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1818350116
更新日期:2019-03-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1214094109
更新日期:2012-10-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1218925110
更新日期:2012-12-18 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.162203299
更新日期:2002-08-20 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.102179699
更新日期:2002-05-28 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1612898113
更新日期:2016-10-04 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1989-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.71.6.2453
更新日期:1974-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2017-04-04 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.89.17.8025
更新日期:1992-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-09-28 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-12-21 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0806668105
更新日期:2008-12-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-12-03 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.1.322
更新日期:1993-01-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0510223103
更新日期:2006-01-17 00:00:00