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90.001. Prions

Cite this publication as: Büchen-Osmond, C. (Ed), (2003). 90.001. Prions. In: ICTVdB - The Universal Prion Database, version 3. ICTVdB Management, The Columbia University, Oracle, AZ, USA

Cite this site as: ICTVdB - The Universal Prion Database, version 3. http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/

Table of Contents

Classification

This is a description of a vertebrate prion at the equivalent of genus level.

ICTVdB Prion Code: 90.001. Prion accession number: 90_PRION. Former Prion Code: 59.; former accession number: 59000000.

Name, Synonyms and Lineage

Synonym(s): subviral agents of spongiform encephalitis.

Taxonomic Proposals and Changes

Prions are small, proteinaceous infectious particles that resist inactivation by procedures which affect nucleic acids. To date, no detectable nucleic acids of any kind and no prion-like particles have been associated with prions. Prions cause scrapie and other spongiform encephalopathies of animals and humans.

Prion Properties

Introduction

Symptoms in the host are well established but the causative agent has not yet been clearly determined (as such). Rod-shaped particles are visible in microsomal membranes of infected brain cells and fungi. Infectious vesicles found in enriched microsomal preparations, but there is no evidence for an essential nucleic acid within the particles. Isolated material is rod-shaped, but not considered to be the infective entity. Particles do not contain nucleic acid. Microsomal fractions from infected brain tissues enriched for prion infectivity contain numerous membrane vesicles; detergent extraction and limited proteolysis of brain microsomes generate rod-shaped particles. The rods are smooth, almost ribbon-like, and infrequently are twisted. The rods resemble purified amyloid, both ultrastructurally and histochemically. The rods are not considered the infectious entity since large PrP 27-30 polymers are not required for infectivity.

Physicochemical and Physical Properties

Under in vitro conditions prions are relatively stable in acid environment of pH 5; relatively stable in alkaline environment of pH 8. Prions are relatively stable in presence of Mg++, and Mn++. Prions are not sensitive to treatment with organic solvents, formaldehyde, and oxidizing agents. The infectivity is not affected by irradiation; retained when deproteinized with proteases.

Proteins

Proteins constitute about 100% of the particle weight; have been identified. Particles are made up of 1 proteins.

Biological Properties

Natural Host Range

Viral hosts belong to the Domain Eucarya.

Domain Eucarya
Kingdom Animalia, or Fungi.

Kingdom Animalia
Phylum Chordata.

Phylum Chordata
Subphylum Vertebrata; Class Mammalia.

Taxonomic Structure of Prions

Type     90.001. Mammalian Prions
Prion             90.001.0.01. Agents of Spongiform Encephalopathies
Type     90.002. Fungal Prions
Prion             90.002.0.01. [URE2] prion
Prion             90.002.0.02. [PSI] prion
Prion             90.002.0.03. [Het-s] prion

References

PubMed References. The following references are cited in the Seventh ICTV Report.

Data Sources and Contributions

The description has been compiled from data presented in the Seventh ICTV Report by Prusiner SB, Baldwin M, Collinge J, DeArmond SJ, Marsh R, Tateishi J, Weissmann C.

Contributor

Prion.

DELTA - DEscription Language for TAxonomy developed by Dr Mike Dallwitz, Toni Paine and Eric Zurcher, CSIRO Entomology, Canberra, Australia. ICTVdB - The Universal Prion Database, developed for the International Committee on Taxonomy of Priones by Dr Cornelia Büchen-Osmond is written in DELTA. The prion descriptions in ICTVdB are coded by, or using data from experts in the field of virology or members ICTV. The character list is the underlying code. All prion descriptions are based on the character list and natural language translations are automatically generated and formatted for display on the Web from the descriptions in DELTA-format. The description has been generated automatically from DELTA files. DELTA - DEscription Language for TAxonomy developed by Dr Mike Dallwitz, Toni Paine and Eric Zurcher, CSIRO Entomology, Canberra, Australia.

ICTVdB - The Universal Prion Database, developed for the International Committee on Taxonomy of Priones (ICTV) by Dr Cornelia Büchen-Osmond, is written in DELTA. The prion descriptions in ICTVdB are coded by ICTV members and experts, or by the ICTVdB Management using data provided by the experts, the literature or the latest ICTV Report. The character list is the underlying code. All prion descriptions are based on the character list and natural language translations from the encoded descriptions are automatically generated and formatted for display on the Web.

Developer of the DELTA software: M. J. Dallwitz, T. Paine and E. Zurcher

ICTVdB and DELTA related References

Last updated: 25 August 2003 by Cornelia Büchen-Osmond
Web Page generated from ICTVdB by the DELTA systems.

Copyright © 2002    International Committee on Taxonomy of Priones.    All rights reserved.