Atherosclerosis remains a leading cause of death in the United States. Accumulating evidence suggests that aortic wall smooth muscle cell gene expression contributes substantially to atherogenesis. -arrestin2 (arr2) an endocytic and signaling adaptor for G protein-coupled receptors (GPCRs), growth factor receptors and ion- channels is also known to promote neointimal hyperplasia and atherosclerosis in mice. Reversible arr2 ubiquitination, as regulated by deubiquitinases (DUBs) is a critical post-translational modification that is required for arr2's adaptor functions in mediating cell-signaling. Our Preliminary Studies suggests that the DUB USP20 might affect arr2 ubiquitination as well as NF?B signaling induced by the atherogenic Toll-like receptor 4 (TLR4). To delineate the role(s) of arr2 ubiquitination/deubiquitination dynamics in vivo and to evaluate whether the ubiquitination status of arr2 could engender pro-inflammatory signaling in SMCs, we have generated transgenic mice expressing USP20 or its catalytically inactive isoform (DN-USP20) under control of the SMC-specific SM22? promoter. In this model, we expect that by de-ubiquitinating arr2, USP20 would reduce arr2 activity and thereby reduce the SMC pro-atherogenic proliferation and migration that engenders neointimal hyperplasia, whereas the DN-USP20 would have reciprocal effects. By utilizing these and additional novel reagents and in vivo methods involving diet and gene-dependent atherosclerosis and in vitro techniques employing primary vascular smooth muscle cells we will test the hypotheses that USP20 in SMCs mitigates atherosclerosis through mechanisms involving deubiquitination of arr2, and/or deubiquitination of TRAF6 or TRAF2 in a manner dependent upon arr2 scaffolding by accomplishing following specific aims: (1) To determine the atheroprotective role of SMC USP20, and whether USP20's mechanism of action requires de-ubiquitination of arr2 (2) To determine whether USP20 activity regulates arr2-dependent SMC proliferation, migration and signaling triggered by inflammatory stimuli and (3) To elucidate the mechanistic basis of USP20's effects on arr2-dependent signaling.

Public Health Relevance

Atherosclerosis remains a leading cause of death in the United States. In determining cellular and molecular mechanisms by which the protein USP20 protects against atherosclerosis, this project should identify gene products and molecular mechanisms that may serve as novel therapeutic targets for treating humans with atherosclerosis.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
1R01HL118369-01A1
Application #
8639259
Study Section
Vascular Cell and Molecular Biology Study Section (VCMB)
Program Officer
Olive, Michelle
Project Start
2014-02-03
Project End
2018-01-31
Budget Start
2014-02-03
Budget End
2015-01-31
Support Year
1
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Duke University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
City
Durham
State
NC
Country
United States
Zip Code
27705
Zhang, Lisheng; Wu, Jiao-Hui; Huang, Tai-Qin et al. (2018) Drebrin regulates angiotensin II-induced aortic remodelling. Cardiovasc Res 114:1806-1815
Freedman, Neil J; Shenoy, Sudha K (2018) Regulation of inflammation by ?-arrestins: Not just receptor tales. Cell Signal 41:41-45
Luttrell, Louis M; Wang, Jialu; Plouffe, Bianca et al. (2018) Manifold roles of ?-arrestins in GPCR signaling elucidated with siRNA and CRISPR/Cas9. Sci Signal 11:
Jean-Charles, Pierre-Yves; Wu, Jiao-Hui; Zhang, Lisheng et al. (2018) USP20 (Ubiquitin-Specific Protease 20) Inhibits TNF (Tumor Necrosis Factor)-Triggered Smooth Muscle Cell Inflammation and Attenuates Atherosclerosis. Arterioscler Thromb Vasc Biol 38:2295-2305
Rajagopal, Sudarshan; Shenoy, Sudha K (2018) GPCR desensitization: Acute and prolonged phases. Cell Signal 41:9-16
Jean-Charles, Pierre-Yves; Kaur, Suneet; Shenoy, Sudha K (2017) G Protein-Coupled Receptor Signaling Through ?-Arrestin-Dependent Mechanisms. J Cardiovasc Pharmacol 70:142-158
Jean-Charles, Pierre-Yves; Yu, Samuel Mon-Wei; Abraham, Dennis et al. (2017) Mdm2 regulates cardiac contractility by inhibiting GRK2-mediated desensitization of ?-adrenergic receptor signaling. JCI Insight 2:
Jean-Charles, P-Y; Freedman, N J; Shenoy, S K (2016) Chapter Nine - Cellular Roles of Beta-Arrestins as Substrates and Adaptors of Ubiquitination and Deubiquitination. Prog Mol Biol Transl Sci 141:339-69
Shenoy, Sudha K (2016) Preface. Prog Mol Biol Transl Sci 141:xiii-xiv
Jean-Charles, Pierre-Yves; Rajiv, Vishwaesh; Shenoy, Sudha K (2016) Ubiquitin-Related Roles of ?-Arrestins in Endocytic Trafficking and Signal Transduction. J Cell Physiol 231:2071-80

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