Altered cleavage and localization of PINK1 to aggresomes in the presence of proteasomal stress.
Following our identification of PTEN-induced putative kinase 1 (PINK1) gene mutations in PARK6-linked Parkinson's disease (PD), we have recently reported that PINK1 protein localizes to Lewy bodies (LBs) in PD brains. We have used a cellular model system of LBs, namely induction of aggresomes, to determine how a mitochondrial protein, such as PINK1, can localize to aggregates. Using specific polyclonal antibodies, we firstly demonstrated that human PINK1 was cleaved and localized to mitochondria. We demonstrated that, on proteasome inhibition with MG-132, PINK1 and other mitochondrial proteins localized to aggresomes. Ultrastructural studies revealed that the mechanism was linked to the recruitment of intact mitochondria to the aggresome. Fractionation studies of lysates showed that PINK1 cleavage was enhanced by proteasomal stress in vitro and correlated with increased expression of the processed PINK1 protein in PD brain. These observations provide valuable insights into the mechanisms of LB formation in PD that should lead to a better understanding of PD pathogenesis.
Muqit
Miratul M K
MM
Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK.
Abou-Sleiman
Patrick M
PM
Saurin
Adrian T
AT
Harvey
Kirsten
K
Gandhi
Sonia
S
Deas
Emma
E
Eaton
Simon
S
Payne Smith
Martin D
MD
Venner
Kerrie
K
Matilla
Antoni
A
Healy
Daniel G
DG
Gilks
William P
WP
Lees
Andrew J
AJ
Holton
Janice
J
Revesz
Tamas
T
Parker
Peter J
PJ
Harvey
Robert J
RJ
Wood
Nicholas W
NW
Latchman
David S
DS
D000818:Animals; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D002460:Cell Line; D003001:Cloning, Molecular / Q000379:methods; D006224:Cricetinae; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005455:Fluorescent Antibody Technique / Q000379:methods; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D007976:Leupeptins / Q000494:pharmacology; D016253:Microscopy, Immunoelectron / Q000379:methods; D008928:Mitochondria / Q000378:metabolism / Q000648:ultrastructure; D050505:Mutant Proteins / Q000235:genetics / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010300:Parkinson Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D046988:Proteasome Endopeptidase Complex; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological / Q000139:chemically induced / Q000378:metabolism*; D014162:Transfection / Q000379:methods; D000099202:PTEN-Induced Putative Kinase
D015853:Cysteine Proteinase Inhibitors; D004791:Enzyme Inhibitors; D049452:Green Fluorescent Proteins; D007976:Leupeptins; D050505:Mutant Proteins; D009419:Nerve Tissue Proteins; D046988:Proteasome Endopeptidase Complex; D011494:Protein Kinases; D000099202:PTEN-Induced Putative Kinase; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde