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Updated: Jul 16, 2026

Assay for Phosphorylation and Microtubule Binding Along with Localization of Tau Protein in Colorectal Cancer Cells
Published on: October 10, 2017
Effects of tau phosphorylation on proteasome activity
Qing-Guo Ren1, Xiao-Mei Liao, Xiao-Qian Chen
1Department of Pathophysiology, Hubei Provincial Key Laboratory of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China.
Abstract:
Dysfunction of proteasome contributes to the accumulation of the abnormally hyperphosphorylated tau in Alzheimer's disease. However, whether tau hyperphosphorylation and accumulation affect the activity of proteasome is elusive. Here we found that a moderate tau phosphorylation activated the trypsin-like activity of proteasome, whereas further phosphorylation of tau inhibited the activity of the protease in HEK293 cells stably expressing tau441. Furthermore, tau hyperphosphorylation could partially reverse lactacystin-induced inhibition of proteasome. These results suggest that phosphorylation of tau plays a dual role in modulating the activity of proteasome.
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