Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2018 Sep 7;9:3648. doi: 10.1038/s41467-018-06041-3

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2018

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

PMC Copyright notice

Fig. 3 — Increased STAU1 abundance caused by abnormal autophagy. a, b Stability of STAU1 in SCA2 FBs. Normal and SCA2 FBs were exposed to CHX (25 µg/ml) for different times from 0 to 24 h, and protein extracts were immunoblotted for STAU1. STAU1 levels are quantified as a percentage of the value for the 0 time point and p21 protein levels are shown to verify CHX inhibition. STAU1 protein stability was prolonged in SCA2 FBs compared to normal FBs. b Quantification of STAU1 on western blots is shown. c ATXN2-Q22/58 KI cells show increased STAU1, p62 and LC3-II levels on western blots. PCP2 level is decreased in this cell model. d, e STAU1 is not degraded by the proteasome pathway. d HEK-293 and ATXN2-Q22/58 KI cells were treated with proteasome inhibitor MG132 (10 µM) or DMSO as control at different time points and cell extracts were analyzed by western blotting. HEK-293 and ATXN2-Q22/58 KI cells show insignificant changes in STAU1 levels compared to controls upon proteasome inhibition. Increased Cyclin B1 protein levels indicate successful proteasome pathway inhibition. e Quantification of STAU1 and Cyclin B1 on western blots. Two-way ANOVA followed by Tukey’s multiple comparison test. Data are mean ± SD, ns = P > 0.05, ***P < 0.001: DMSO vs. MG132 treated groups (6 and 8 h for HEK-293 cells, and each time points for ATXN2-Q22/58 KI cells). f–h Inefficient autophagy in the presence of mutant ATXN2. f SCA2 FBs show inefficient autophagosome-lysosome fusion as indicated by increased LC3-II levels on western blots. g, h Bafilomycin A1 (Baf) lowers STAU1 clearance through inefficient autophagosome-lysosome fusion. g HEK-293 and ATXN2-Q22/58 KI cells were treated dose-wise with Baf for 6 h and analyzed by western blotting. Baf treatment showing dose-wise increased levels of LC3-II and p62 levels and significant increases in STAU1 levels for both cell types compared to untreated cells. h Quantification of STAU1 on western blots. One-way ANOVA followed by Tukey’s multiple comparison test. Data are mean ± SD, ns = P > 0.05, **P < 0.01, ***P < 0.001. β-Actin was used as loading control. Representative blots of three independent experiments are shown