Function
Prions are proteins with compromised folds in their structure. They can convert a normal protein into a replicate of their own abnormal form. This can lead to deadly degenerative diseases of the brain. Studies have shown that prions are linked to Alzheimer's and Parkinson's disease.[1]
Disease
There are different prions that arise from different conditions. Prion diseases are usually obtained via the consumption of infected meat products. Creutzfeldt-Jakob is the most common form of the disease that affects humans. Prions are found abnormally clustered in the brain. CJD can be inherited, so it is usually associated with family occurrences, thus given the name familial CJD. CJD also can also develop in individuals that are at the age of 60 years old. CJD can also be acquired through infected tissue and lack of sterilization in a medical procedure. An example of such acquired CJD in procedure would be a cornea transplant.[2]
Variant CJD is one of the different kind of prion disease that is related to the infamous mad cow disease. This CJD can be obtained through the consumption of diseased meat. This variant of the disease usually affects younger individuals.[2]
Variable protease (VPSPRr) Another variant of disease, sensitive prionopathy is a very rare condition that affects individuals around the age of 70 years old. It is Like CJD, however, the protein is not digested easily. This variant of the disease usually occurs in an individual who has history of dementia in their family.[2]
The symptoms can lead to a severe disability due to the important functions that proteins are responsible for. It can also lead to death, however, studies show in most cases death occurs within a year.[2]
Gerstmann- Straussler Scheinker disease is another extremely rare variant that presents itself at an early age in individuals around 40. Kuru is also a variant that was commonly seen in New Guinea. This variant presents itself after the consumption of human brain tissue, usually after the death of the individual, so the tissue is usually infected by prions at the time.[2]
The last variant is fatal insomnia, which is also a very rare hereditary disorder that makes the individual have difficulty sleeping. There is a sporadic version of this type that can be acquired not through inheritance.[2]
The disease cannot be cured, however, it can be managed through medications to slow the progression.
Structural highlights
There are three alpha helices and a long side chain.
The side chain is illustrated in ball and stick form, making it easier to identify the sulfide bond in the side chain.
They are responsible for the tight binding of H3 to H1 because of they are aromatic. The different positions: H1, H2, and H3 respective helices contain these side chains in the protein.There are disulfide bonds that help link the alpha helices.
