There is increasing evidence that unfolded and misfolded proteins initiate a cascade of pathogenic protein-protein interactions that culminates in neuronal dysfunction.This is multistep process which results in protein aggregates with distinct toxicity; thus they are potent drug targets.A couple of hallmark proteins have been identified involved in Parkinson, Alzheimer or Huntington diseases, which do not have well-defined 3D structures and require protein partners to express their pathological functions.