In Vitro Phosphorylation Does not Influence the Aggregation Kinetics of WT α-Synuclein in Contrast to Its Phosphorylation Mutants

International Journal of Molecular Sciences

Sarah Schreurs²  Melanie Gerard⁴  Rita Derua³  Etienne Waelkens³  Jean-Marc Taymans¹  Veerle Baekelandt¹ 

[1] Laboratory for Neurobiology and Gene Therapy, KU Leuven, Kapucijnenvoer 33, Leuven B-3000, Belgium;Laboratory of Biomolecular Dynamics, KU Leuven, Celestijnenlaan 200G, Leuven B-3001, Belgium; E-Mail:;Laboratory of Protein Phosphorylation and Proteomics, KU Leuven, O&N I Herestraat 49-bus 901, Leuven B-3000, Belgium; E-Mails:;Laboratory of Biochemistry, KU Leuven Kulak, Etienne Sabbelaan 53, Kortrijk B-8500, Belgium; E-Mail:

关键词: alpha-synuclein;    phosphorylation;    parkinson’s disease;    phosphorylation mutants;    FKBP;    in vitro fibrillization;   

DOI  :  10.3390/ijms15011040

来源: mdpi

【 摘 要 】

The aggregation of alpha-synuclein (α-SYN) into fibrils is characteristic for several neurodegenerative diseases, including Parkinson’s disease (PD). Ninety percent of α-SYN deposited in Lewy Bodies, a pathological hallmark of PD, is phosphorylated on serine129. α-SYN can also be phosphorylated on tyrosine125, which is believed to regulate the membrane binding capacity and thus possibly its normal function. A better understanding of the effect of phosphorylation on the aggregation of α-SYN might shed light on its role in the pathogenesis of PD. In this study we compare the aggregation properties of WT α-SYN with the phospho-dead and phospho-mimic mutants S129A, S129D, Y125F and Y125E and in vitro phosphorylated α-SYN using turbidity, thioflavin T and circular dichroism measurements as well as transmission electron microscopy. We show that the mutants S129A and S129D behave similarly compared to wild type (WT) α-SYN, while the mutants Y125F and Y125E fibrillate significantly slower, although all mutants form fibrillar structures similar to the WT protein. In contrast, in vitro phosphorylation of α-SYN on either S129 or Y125 does not significantly affect the fibrillization kinetics. Moreover, FK506 binding proteins (FKBPs), enzymes with peptidyl-prolyl cis-trans isomerase activity, still accelerate the aggregation of phosphorylated α-SYN in vitro, as was shown previously for WT α-SYN. In conclusion, our results illustrate that phosphorylation mutants can display different aggregation properties compared to the more biologically relevant phosphorylated form of α-SYN.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland