PrP^Sc (Prion Scrapie Form)

PrP^Sc is a misfolded version of a normal protein found in the brain called PrP (prion protein). In its normal form (PrP^C), it plays a role in cell functions, but when it misfolds into PrP^Sc, it becomes pathogenic. PrP^Sc is infectious because it can induce healthy proteins to also misfold, leading to the accumulation of abnormal proteins that damage brain tissue. This process is associated with transmissible neurodegenerative diseases like scrapie in sheep and Creutzfeldt-Jakob disease in humans. Essentially, PrP^Sc is a rogue protein that disrupts normal brain function through a self-propagating misfolding mechanism.