Maintenance of chaperone‑mediated autophagy activity in cultured cells expressing mutant huntingtin

Li,Xiang; Wang,Jianbin

doi:10.3892/br.2014.278

Maintenance of chaperone‑mediated autophagy activity in cultured cells expressing mutant huntingtin

Authors:
- Xiang Li
- Jianbin Wang
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Affiliations: Department of Medical Genetics and Cell Biology, Basic Medical Science, Nanchang University, Nanchang, Jiangxi 330046, P.R. China, Institute of Translational Medicine, Nanchang University, Nanchang, Jiangxi 330031, P.R. China
Published online on: May 16, 2014 https://doi.org/10.3892/br.2014.278
Pages: 529-532

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Abstract

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by mutant huntingtin (Htt) with an expanded polyglutamine tract. It has been reported that Htt regulates autophagy. However, it remains unclear whether mutant Htt affects chaperone‑mediated autophagy (CMA). Our study aimed to investigate the effect of mutant Htt on CMA activity in cultured HEK293T cells. A HEK293T cell model of HD was produced by transient transfection of wild‑type (20Q) or mutant (120Q) Htt plasmids. The effect of mutant Htt on two CMA components, lysosomal‑associated membrane protein 2a (Lamp2a) and heat‑shock cognate protein 70 (Hsc70), was determined by western blotting and immunofluorescent staining. We observed that mutant Htt did not significantly alter the expression of Lamp2a and Hsc70 when compared to normal Htt. These findings suggest that mutant Htt does not reduce CMA activity and that enhancing CMA activity to clear mutant Htt may be a novel strategy for the management of HD.

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