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Journal of Zhejiang University SCIENCE B 2011 Vol.12 No.12 P.951-960


Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells

Author(s):  Jing Liang, Tan Li, Ya-li Zhang, Zong-lou Guo, Li-hong Xu

Affiliation(s):  Department of Biochemistry and Genetics, School of Medicine, Zhejiang University, Hangzhou 310058, China, Department of Biosystem Engineering, College of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou 310058, China

Corresponding email(s):   zlguo@zju.edu.cn, xulihong@zju.edu.cn

Key Words:  Microcystin-LR, Protein phosphatase 2A, Phosphatase activity, Hormesis, Tubulin, B55α

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Jing Liang, Tan Li, Ya-li Zhang, Zong-lou Guo, Li-hong Xu. Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells[J]. Journal of Zhejiang University Science B, 2011, 12(12): 951-960.

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author="Jing Liang, Tan Li, Ya-li Zhang, Zong-lou Guo, Li-hong Xu",
journal="Journal of Zhejiang University Science B",
publisher="Zhejiang University Press & Springer",

%0 Journal Article
%T Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells
%A Jing Liang
%A Tan Li
%A Ya-li Zhang
%A Zong-lou Guo
%A Li-hong Xu
%J Journal of Zhejiang University SCIENCE B
%V 12
%N 12
%P 951-960
%@ 1673-1581
%D 2011
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.B1100121

T1 - Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells
A1 - Jing Liang
A1 - Tan Li
A1 - Ya-li Zhang
A1 - Zong-lou Guo
A1 - Li-hong Xu
J0 - Journal of Zhejiang University Science B
VL - 12
IS - 12
SP - 951
EP - 960
%@ 1673-1581
Y1 - 2011
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.B1100121

Due to their toxicity, the increased distribution of microcystins (MCs) has become an important worldwide problem. MCs have been recognized as inhibitors of protein phosphatase 2A (PP2A) through their binding to the PP2A catalytic subunit. However, the exact mechanism of MC toxicity has not been elucidated, especially concerning the cellular response and its autoregulation. To further dissect the role of PP2A in MC-induced toxicity, the present study was undertaken to determine the response of PP2A in human amniotic epithelial (FL) cells treated with microcystin-LR (MCLR), one of the MC congeners. The results show that a low-dose treatment of MCLR in FL cells for 6 h induced an increase in PP2A activity, and a high-dose treatment of MCLR for 24 h decreased the activity of PP2A, as expected. The increased mRNA and protein levels of the PP2A C subunit may explain the increased activity of PP2A. Furthermore, MCLR altered microtubule post-translational modifications through PP2A. These results further clarify the underlying mechanism how MCLR affects PP2A and may be helpful for elucidating the complex toxicity of MCLR.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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