title: Effects of tau phosphorylation on proteasome activity.
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.
authors: Department of Pathophysiology, Hubei Provincial Key Laboratory of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China.
authors: Qing-Guo
authors: QG
authors: Ren
authors: Xiao-Mei
authors: XM
authors: Liao
authors: Xiao-Qian
authors: XQ
authors: Chen
authors: Gong-Ping
authors: GP
authors: Liu
authors: Jian-Zhi
authors: JZ
authors: Wang
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D006801:Humans; D019319:Okadaic Acid / Q000494:pharmacology; D010766:Phosphorylation; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D061988:Proteasome Inhibitors; D016875:tau Proteins / Q000378:metabolism*
chemical_list: D015853:Cysteine Proteinase Inhibitors; D061988:Proteasome Inhibitors; D016875:tau Proteins; C067713:lactacystin; D005576:Colforsin; D019319:Okadaic Acid; D046988:Proteasome Endopeptidase Complex; D000111:Acetylcysteine