Regulation of TDP-43 aggregation by phosphorylation and p62/SQSTM1 |
| |
Authors: | Brady Owen A Meng Peter Zheng Yanqiu Mao Yuxin Hu Fenghua |
| |
Institution: | Weill Institute for Cell and Molecular Biology, Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA. |
| |
Abstract: | TAR DNA-binding protein-43 (TDP-43) proteinopathy has been linked to several neurodegenerative diseases, such as frontotemporal lobar degeneration with ubiquitin-positive inclusions and amyotrophic lateral sclerosis. Phosphorylated and ubiquitinated TDP-43 C-terminal fragments have been found in cytoplasmic inclusions in frontotemporal lobar degeneration with ubiquitin-positive inclusions and amyotrophic lateral sclerosis patients. However, the factors and pathways that regulate TDP-43 aggregation are still not clear. We found that the C-terminal 15 kDa fragment of TDP-43 is sufficient to induce aggregation but the aggregation phenotype is modified by additional sequences. Aggregation is accompanied by phosphorylation at serine residues 409/410. Mutation of 409/410 to phosphomimetic aspartic acid residues significantly reduces aggregation. Inhibition of either proteasome or autophagy dramatically increases TDP-43 aggregation. Furthermore, TDP-43 aggregates colocalize with markers of autophagy and the adaptor protein p62/SQSTM1. Over-expression of p62/SQSTM1 reduces TDP-43 aggregation in an autophagy and proteasome-dependent manner. These studies suggest that aggregation of TDP-43 C-terminal fragments is regulated by phosphorylation events and both the autophagy and proteasome-mediated degradation pathways. |
| |
Keywords: | aggregation autophagy p62/SQSTM1 phosphorylation proteasome TDP‐43 |
本文献已被 PubMed 等数据库收录! |
|