Search results
Results from the WOW.Com Content Network
A prion / ˈ p r iː ɒ n / ⓘ is a misfolded protein that induces misfolding in normal variants of the same protein, leading to cellular death.Prions are responsible for prion diseases, known as transmissible spongiform encephalopathy (TSEs), which are fatal and transmissible neurodegenerative diseases affecting both humans and animals.
In some types of prion in fungi this change is continuous and direct; the information flow is Protein → Protein. Some scientists such as Alain E. Bussard and Eugene Koonin have argued that prion-mediated inheritance violates the central dogma of molecular biology.
Several prion-forming proteins have been identified in fungi, primarily in the yeast Saccharomyces cerevisiae. These fungal prions are generally considered benign, and in some cases even confer a selectable advantage to the organism. [1] Fungal prions have provided a model for the understanding of disease-forming mammalian prions. Study of ...
The abnormal protein PrP Sc accumulates in the brain and destroys nerve cells, which leads to the mental and behavioral features of prion diseases. [citation needed] Several other changes in the PRNP gene (called polymorphisms) do not cause prion diseases but may affect a person's risk of developing these diseases or alter the course of the ...
It is, however, classified with the transmissible spongiform encephalopathies (TSE) due to the causative role played by PRNP, the human prion protein. [2] GSS was first reported by the Austrian physicians Josef Gerstmann, Ernst Sträussler and Ilya Scheinker in 1936. [3] [4] Familial cases are associated with autosomal-dominant inheritance. [5]
The amino terminus can differ substantially across the proteins. The prion-like isoform of CPEB found in Aplysia californica, Drosophila, mice, and humans is an example of such differentiation. [5] This isoform is prion-like due to the presence of polyglutamine- or polyalanine-rich domains at the N-terminus. [5]
In his 1998 PNAS review article on Prions, Prusiner wrote: [10] "The idea that scrapie prions were composed of an amyloidogenic protein was truly heretical when it was introduced" (by Tikvah Alper [11] [12]). Encephalopathy was a mysterious disease that attacks the brain, and leaves the brains of its victims full of holes.
Circularization of the mRNA transcript is mediated by proteins interacting with the 5' cap and poly(A) tail. The poly(A) tail contains binding sites for poly(A) binding proteins (PABPs). These proteins cooperate with other factors to affect the export, stability, decay, and translation of an mRNA.