Prion protein (PrPc) interacts with histone H3 confirmed by affinity chromatography

The histones including H2a, H2b, H3 and H4 purified from pig liver tissue were immobilized onto Sepharose 4B to create a histone-Sepharose column. During chromatography of cow milk casein by histone-Sepharose column, two isoforms of prion protein (PrPc) with 34 and 30 kDa molecular mass corresponding to diglycosylated and monoglycosylated PrPc respectively were found to be captured by histone ligands. To further verify the interaction between histones and PrPc, the PrPc-Sepharose column was prepared and used to separate the histones. Two chromatography processes and SDS-PAGE demonstrated that only H3 in the histones was found to interact with PrPc. This study suggested H3 could be the target molecule of PrPC in nuclei, which might be useful for understanding the prion disease.