Fibril formation rewires interactome of the Alzheimer protein Tau by π-stacking

Ferrari, L.; Stucci, R.; Konstantoulea, A.; van de Kamp, G.; Kos, R.; Geerts, W. J. C.; Forster, F. G.; Altelaar, M.; Hoogenraad, C.; Rudiger, S. G. D.

doi:10.1101/522284

bioRxiv · 10.1101/522284

Fibril formation rewires interactome of the Alzheimer protein Tau by π-stacking

Ferrari, L.·Stucci, R.·Konstantoulea, A.·van de Kamp, G.·Kos, R.·Geerts, W. J. C.·Forster, F. G.·Altelaar, M.·Hoogenraad, C.·Rudiger, S. G. D.

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Abstract

Aggregation of the Tau protein defines progression of neurodegenerative diseases, including Alzheimers Disease. Tau assembles into oligomers and fibrils. The molecular basis of their toxicity is poorly understood. Here we show that {pi}-stacking by Arginine side chains rewires the interactome of Tau upon aggregation. Oligomeric nano-aggregates scavenge the COPI complex, fibrils attract proteins involved in microtubule binding, RNA binding and phosphorylation. The aberrant interactors have disordered regions with unusual sequence features. Arginines are crucial to initiate such aberrant interactions. Remarkably, substitution of Arginines by Lysines abolishes scavenging, which indicates a key role for the pi-stacking of the Arginine side chain. The molecular chaperone Hsp90 tames such re-arrangements, which suggests that the natural protein quality control system can suppress aberrant interactions. Together, our data present a molecular mode of action for derailment of protein-protein interaction in neurodegeneration.\n\nHIGHLIGHTSO_LITau fibrils act as fishing net for proteins.\nC_LIO_LITau fibrils attract specific protein families associated with Alzheimer.\nC_LIO_LI{pi}-stacking by Arginines key for aberrant binding to Tau fibrils\nC_LIO_LIThe Hsp90 chaperone stalls fibril growth and alters interactome\nC_LI

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Ferrari, L., Stucci, R., Konstantoulea, A., van de Kamp, G., Kos, R., Geerts, W. J. C., Forster, F. G., Altelaar, M., Hoogenraad, C., Rudiger, S. G. D.. 2019-01-16. Fibril formation rewires interactome of the Alzheimer protein Tau by π-stacking. https://doi.org/10.1101/522284

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