Related Experiment Video
Updated: Jul 13, 2026

12:57
Investigating the Spreading and Toxicity of Prion-like Proteins Using the Metazoan Model Organism C. elegans
Published on: January 8, 2015
Prion protein and the transmissible spongiform encephalopathies
Trends in Cell Biology
|February 1, 1997
Summary
Transmissible spongiform encephalopathies (TSEs) are fatal brain diseases affecting mammals. This review examines the role of the prion protein (PrP) in TSE pathogenesis and transmission.
Area of Science:
- Neuroscience
- Veterinary Medicine
- Infectious Diseases
Background:
- Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases affecting various mammals.
- Human TSEs include Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia (FFI).
- Animal TSEs like scrapie in sheep and bovine spongiform encephalopathy (BSE) pose significant agricultural and public health concerns, with a new variant CJD linked to BSE.
Purpose of the Study:
- To review the current understanding of TSEs, focusing on the central role of the prion protein (PrP).
- To discuss the pathogenic mechanisms and the nature of the transmissible agent in TSEs.
- To highlight the ongoing research and controversies surrounding PrP's involvement in disease causation.
Main Methods:
- Review of existing scientific literature on TSEs.
- Analysis of the biochemical and pathological properties of the prion protein (PrP).
- Discussion of epidemiological data and suspected transmission routes.
Main Results:
- The abnormal isoform of the host prion protein (PrP) is a critical component in the pathogenesis of all TSEs.
- The exact nature of the transmissible agent and its relationship with PrP remains a subject of intense research and debate.
- Evidence suggests a link between BSE in cattle and a new variant of CJD in humans, underscoring zoonotic potential.
Conclusions:
- Prion protein (PrP) is essential for TSE development and is central to understanding these diseases.
- Further research is needed to fully elucidate the prion's role and the mechanisms of TSE transmission.
- The emergence of variant CJD highlights the importance of monitoring and controlling TSEs in animal populations to protect public health.
Related Concept Videos
Subviral Agents
Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...
Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Cotranslational Protein Translocation
Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Protein Translocation Machinery on the ER Membrane
The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Post-translational Translocation of Proteins to the RER
A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...

