Mechanism of BAG1 repair on Parkinson's disease-linked DJ1 mutation.

Mutant oncogene DJ1 L166P has been linked to a familial form of early-onset Parkinson's disease (PD). The DJ1 mutant deformed C-terminal helices and prevented the formation of a functional DJ1 dimer. Intriguingly, chaperon modulator, BCL2-associated athanogene (BAG1), has been shown to repair DJ1 mutant and restore its functions. Molecular simulation techniques were employed to elucidate protein-protein interactions between BAG1 and DJ1. Interaction of BAG1 with DJ1 showed recovery of disrupted alpha helix structures and H-bonds stabilizing the functional site Cys106. The His126-Pro184 H-bond (hydrogen-bond) critical to maintaining dimer interfaces was also restored and led to the restoration of dimer formation. High conformational to functional DJ1 dimer was confirmed root mean square deviation = 0.74 Å). Results of this suggest several molecular insights on BAG1-DJ1 repair mechanism and may have an impact on advancing PD treatments.