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bioRxiv · 10.1101/2020.10.04.325134

EGCG modulates nuclear formaldehyde-induced Tau phosphorylation in Neuronal cells

Sonawane, S. K.·Raina, A.·Majumdhar, A.·Chinnathambi, S.
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Abstract

Tau hyperphosphorylation is one of the major causes of Alzheimers disease pathology. The abnormal phosphorylation curtails the physiological function of Tau of microtubule stabilization and renders it more prone to aggregation. Apart from its function in the cytoplasm, Tau is attributed to play a role in the nucleus. Nuclear function of Tau is dependent on its residue-specific phosphorylation. We studied the effect of a green tea polyphenol, EGCG, on the formaldehyde-induced Tau phosphorylation and Tau kinase CDK5. Interestingly, we observed unique localization of phospho-Tau (AT 8 and AT 100) in the nucleus in various EGCG treatments. EGCG was also found to lower the levels of CDK5 in the formaldehyde-treated cells. Further, the role of EGCG was tested in vivo in drosophila eye model of hyperphosphorylated Tau (Tau E14). The results suggest that EGCG can modulate nuclear Tau phosphorylation and lower the levels of Tau kinase CDK5.

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Sonawane, S. K., Raina, A., Majumdhar, A., Chinnathambi, S.. 2020-10-05. EGCG modulates nuclear formaldehyde-induced Tau phosphorylation in Neuronal cells. https://doi.org/10.1101/2020.10.04.325134

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