Parkinson's disease protein DJ-1 regulates ATP synthase protein components to increase neuronal process outgrowth
2019-06-13,
Chen, Rongmin,
Park, Han-A,
Mnatsakanyan, Nelli,
Niu, Yulong,
Licznerski, Pawel,
Wu, Jing,
Miranda, Paige,
Graham, Morven,
Tang, Jack,
Boon, Agnita J. W.,
Cossu, Giovanni,
Mandemakers, Wim,
Bonifati, Vincenzo,
Smith, Peter J. S.,
Alavian, Kambiz N.,
Jonas, Elizabeth A.
Familial Parkinson’s disease (PD) protein DJ-1 mutations are linked to early onset PD. We have found that DJ-1 binds directly to the F1FO ATP synthase β subunit. DJ-1’s interaction with the β subunit decreased mitochondrial uncoupling and enhanced ATP production efficiency while in contrast mutations in DJ-1 or DJ-1 knockout increased mitochondrial uncoupling, and depolarized neuronal mitochondria. In mesencephalic DJ-1 KO cultures, there was a progressive loss of neuronal process extension. This was ameliorated by a pharmacological reagent, dexpramipexole, that binds to ATP synthase, closing a mitochondrial inner membrane leak and enhancing ATP synthase efficiency. ATP synthase c-subunit can form an uncoupling channel; we measured, therefore, ATP synthase F1 (β subunit) and c-subunit protein levels. We found that ATP synthase β subunit protein level in the DJ-1 KO neurons was approximately half that found in their wild-type counterparts, comprising a severe defect in ATP synthase stoichiometry and unmasking c-subunit. We suggest that DJ-1 enhances dopaminergic cell metabolism and growth by its regulation of ATP synthase protein components.