Phosphorylation of synucleins by members of the Polo-like kinase family.
Phosphorylation of alpha-synuclein (alpha-syn) at Ser-129 is a hallmark of Parkinson disease and related synucleinopathies. However, the identity of the natural kinases and phosphatases responsible for regulating alpha-syn phosphorylation remain unknown. Here we demonstrate that three closely related members of the human Polo-like kinase (PLK) family (PLK1, PLK2, and PLK3) phosphorylate alpha-syn and beta-syn specifically at Ser-129 and Ser-118, respectively. Unlike other kinases reported to partially phosphorylate alpha-syn at Ser-129 in vitro, phosphorylation by PLK2 and PLK3 is quantitative (>95% conversion). Only PLK1 and PLK3 phosphorylate beta-syn at Ser-118, whereas no phosphorylation of gamma-syn was detected by any of the four PLKs (PLK1 to -4). PLK-mediated phosphorylation was greatly reduced in an isolated C-terminal fragment (residues 103-140) of alpha-syn, suggesting substrate recognition via the N-terminal repeats and/or the non-amyloid component domain of alpha-syn. PLKs specifically co-localized with phosphorylated Ser-129 (Ser(P)-129) alpha-syn in various subcellular compartments (cytoplasm, nucleus, and membranes) of mammalian cell lines and primary neurons as well as in alpha-syn transgenic mice, especially cortical brain areas involved in synaptic plasticity. Furthermore, we report that the levels of PLK2 are significantly increased in brains of Alzheimer disease and Lewy body disease patients. Taken together, these results provide biochemical and in vivo evidence of alpha-syn and beta-syn phosphorylation by specific PLKs. Our results suggest a need for further studies to elucidate the potential role of PLK-syn interactions in the normal biology of these proteins as well as their involvement in the pathogenesis of Parkinson disease and other synucleinopathies.
Mbefo
Martial K
MK
Laboratory of Molecular Neurobiology and Neuroproteomics, Brain Mind Institute, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland.
Paleologou
Katerina E
KE
Boucharaba
Ahmed
A
Oueslati
Abid
A
Schell
Heinrich
H
Fournier
Margot
M
Olschewski
Diana
D
Yin
Guowei
G
Zweckstetter
Markus
M
Masliah
Eliezer
E
Kahle
Philipp J
PJ
Hirling
Harald
H
Lashuel
Hilal A
HA
D000544:Alzheimer Disease / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism*; D007668:Kidney / Q000166:cytology; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009474:Neurons / Q000166:cytology / Q000201:enzymology*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010300:Parkinson Disease / Q000378:metabolism*; D010766:Phosphorylation / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014162:Transfection; D025521:Tumor Suppressor Proteins; D051846:beta-Synuclein / Q000235:genetics / Q000378:metabolism*; D000097869:Polo-Like Kinase 1; D000097868:Polo-like Kinases
D018797:Cell Cycle Proteins; D007381:Intermediate Filament Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D034741:RNA, Small Interfering; D025521:Tumor Suppressor Proteins; D051846:beta-Synuclein; D000097869:Polo-Like Kinase 1; C430456:desmuslin; C486256:PLK3 protein, human; D000097868:Polo-like Kinases; C490219:PLK4 protein, human; C496126:PLK2 protein, human