At the molecular level, the difference between Doctor Jekyll and Mr Hyde lies in a metal, copper. In its physiological form, the prion protein (PrPC ) is ‘good’ and is involved in normal body processes. It can happen, however, that because of some as yet unknown mechanism, it changes form and turns into a threat for the health of humans and animals (it is responsible for neurodegenerative diseases such as spongiform encephalopathies). According to a new SISSA study, the mechanism underlying this change is a metal, copper, or rather a particular region of the protein to which the metal binds, which acts as a sort of 'switch’ that turns PrPC into its terrible alter ego.
“We still don’t know what complex molecular mechanisms cause the prion protein to become bad,” explains Giuseppe Legname, professor at the International School for Advanced Studies (SISSA) in Trieste who coordinated the new study, “nor do we know any treatments to cure prion diseases. Our research has finally uncovered a critical cofactor, which is capable of triggering the transformation of prions proteins from good to bad. And this cofactor is copper which binds to an amino acid sequence of the prion protein, known as 'fifth copper binding site’, which has so far been poorly studied”
Caption:This is a photograph showing how PrPC turns into a Prion. Credit: SISSA