How prions transmit disease But how does the prion transmit the disease?
This is a puzzle with many of the pieces still missing. The key seems to be that most of the time the natural protein is folded into a tight ball, one of two shapes the proteins can assume. It is when the prion unfolds into the second, more linear form that it becomes dangerous.When an unfolded prion touches one of the proteins in the folded state, the second one unfolds setting off a chain reaction. One molecule after another unravels. It is similar to crystals of ice spreading through a glass of water as the water falls below freezing temperature. An unfolded prion that enters the brain of a person or animal that has eaten infected tissue sets off a massive process of unfolding that turns the entire brain into a spongy remnant of itself.But the prions can also unfold spontaneously on their own. This seems to be the cause of classic CJD that strikes one in a million people worldwide. As the transplant and growth hormone cases prove, a spontaneous case becomes infectious if a piece of
