[Frontiers in Bioscience, Landmark, 21, 192-202, January 1, 2016]

Nuclear factor erythroid-2 related factor 2 (Nrf2)-mediated protein quality control in cardiomyocytes

Taixing Cui 1 , Yimu Lai 1 , Joseph S. Janicki 1 , Xuejun Wang 2

1Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, 29209, USA, 2Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion, SD 57069, USA

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Nrf2 in the UPS
4. Nrf2 in autophagy
5. Nrf2-mediated PQC in cardiomyocytes
6. A summary and future directions
7. Acknowledgements
8. References

1. ABSTRACT

Protein quality control (PQC) acts to minimize the level and toxicity of malfolded proteins in the cell. It is performed by an elaborate network of molecular chaperones and targeted protein degradation pathways. PQC monitors and maintains protein homeostasis or proteostasis in the cells. Whilst chaperones may actively promote refolding of malfolded proteins, the malfolded proteins which cannot be correctly refolded are degraded by the ubiquitin proteasome system (UPS) and the autophagic-lysosome pathway (ALP). The UPS degrades individual misfolded protein molecules, whereas the ALP removes large and less soluble protein aggregates and organelles. Emerging evidence indicates that dysregulated and inadequate PQC play an important role in the pathogenesis of not only classic conformational disease but more common forms of cardiac pathology such as cardiac pathological hypertrophy and heart failure. Nuclear factor erythroid 2-related factor 2 (Nrf2), a master transcription factor of cellular defense, appears to regulate the USP and the ALP by directly controlling the expression of UPS-and ALP-related genes. This article highlights an emerging role of Nrf2 in the regulation of intracellular PQC as well as its potential involvement in cardiac pathology.

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Key Words: autophagy; nuclear factor erythroid-2 related factor 2; proteasome; protein quality control

Send correspondence: Xuejun Wang, Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, Vermillion, SD 57069, USA, Tel: 605-658-6345, Fax: 605 677-6381, E-mail: xuejun.wang@usd.edu