Beyond Viruses…Beyond Viroids…

Can create an “infection” that can lead to the death of the “infected organism?…appears to be able to replicate itself……is not a bacteria!…is smaller than a virus? …is not a virus!…contains no genetic information…whose structure is made by all living things…

PRIONS: The Brain Eater…

A PRION is a… PROteinaceous INfectious particle.

This simply means that a protein can cause a particular disease and it can

be given to another individual and they can then get the same disease.

HYPOTHESIS

PRIONS: DID YOU KNOW…

•People often assume that scientists try to prove hypotheses or theories.

•WRONG•Hypotheses can never be proved; they can only be disproved. •A hypothesis that fails one or more tests is considered disproved and it is discarded. •A valid hypothesis can be revised.

PRIONS: The Brain Eater…

In Class Reading…

The History of Scrapie, CDJ and Kuru

PRIONS: Are PRIONs a new form of life?

1- Are PRIONs made of cell?NO

2- Are PRIONs organized? YES

3- Do PRIONs use energy?NO

4- Are PRIONs responsive?NO (hypothesized)

5- Do PRIONs grow? (enlarge and divide)NO

6- Do PRIONs reproduce? YES (hypothesized)

~kind of, they recruit normal proteins by changing their shape7- Do PRIONs adapt?

Don’t know yet, they may mutate in other viable forms however.

PRIONS: Are PRIONs a new form of life?

8- Do PRIONs die? NO,

however like all proteins, their structure can be degraded or denatured by heat.9- Do PRIONs come from pre-existing prions?

YES (hypothesized) ~ existing PRIONs convert normal Prion-like protein structures into abnormal viable PRION geometries.

PRIONS: Are PRIONs a new form of life?

PRIONS: Origin & Structure

Pre-infectious prion proteins or PrPc, like this one are naturally created by and are found in the membranes of normal host cells. FACT

PRIONS: Origin & Structure

All mammals appear to have prion protein genes and the gene sequences are similar, but not identical, in related species.

FACT

PRIONS: Transformations

PRIONS: Transformations

PRIONS: Infection

O – Origin of PRIONsContaminated

meat Digestive TrackBlood Stream

L – White Blood CellS – SpleenN – Spleen to Brain B – Brain

HYPOTHESIS

PRIONS: Transformation

HYPOTHESIS

Nerve Cell

Normal PrionProtein

Rouge Infectious PRION >

Rouge PRION Transforms

Normal Prion

PRIONS: Shape Transformation

Normal Prions

Infectious PRIONS

Before

AFTER

“Shape

Shifting”

PRIONS: Shape Transformation

Normal Prions

Infectious PRIONS

Before

AFTER

PRIONS: What is the evidence?

Normal Brain Tissue

AFTER

Before

Diseased Brain Tissue

Amyloid Clusters

“Dead Space”

PRIONS: What is the Impact?

One part of the prion protein can cause apoptosis, or programmed cell death;

HYPOTHESIS

FACT

…perhaps this mechanism explains the pattern of the disease.

PRIONS: What is the Impact?

Prions induce no immune reactions within the human.

HYPOTHESIS

FACT

…perhaps this mechanism explains the pattern of the disease.