例如:"lncRNA", "apoptosis", "WRKY"

Kelch-like protein 42 is a profibrotic ubiquitin E3 ligase involved in systemic sclerosis.

J Biol Chem. 2020 Mar 27;295(13):4171-4180. Epub 2020 Feb 17
Travis B Lear 1 , Karina C Lockwood 2 , Mads Larsen 2 , Ferhan Tuncer 2 , Jason R Kennerdell 2 , Christina Morse 3 , Eleanor Valenzi 3 , Tracy Tabib 3 , Michael J Jurczak 4 , Daniel J Kass 5 , John W Evankovich 6 , Toren Finkel 7 , Robert Lafyatis 3 , Yuan Liu 8 , Bill B Chen 9
Travis B Lear 1 , Karina C Lockwood 2 , Mads Larsen 2 , Ferhan Tuncer 2 , Jason R Kennerdell 2 , Christina Morse 3 , Eleanor Valenzi 3 , Tracy Tabib 3 , Michael J Jurczak 4 , Daniel J Kass 5 , John W Evankovich 6 , Toren Finkel 7 , Robert Lafyatis 3 , Yuan Liu 8 , Bill B Chen 9
+ et al

[No authors listed]

Author information
  • 1 Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania 15261; Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 2 Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 3 Division of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 4 Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 5 Dorothy P. and Richard P. Simmons Center for Interstitial Lung Disease, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 6 Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 7 Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Division of Cardiology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
  • 8 Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213. Electronic address: liuy13@upmc.edu.
  • 9 Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Vascular Medicine Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213. Electronic address: chenb@upmc.edu.

摘要


Systemic scleroderma (SSc) is an autoimmune disease that affects over 2.5 million people globally. SSc results in dysfunctional connective tissues with excessive profibrotic signaling, affecting skin, cardiovascular, and particularly lung tissue. Over three-quarters of individuals with SSc develop pulmonary fibrosis within 5 years, the main cause of SSc mortality. No approved medicines to manage lung SSc currently exist. Recent research suggests that profibrotic signaling by transforming growth factor β (TGF-β) is directly tied to SSc. Previous studies have also shown that ubiquitin E3 ligases potently control TGF-β signaling through targeted degradation of key regulatory proteins; however, the roles of these ligases in SSc-TGF-β signaling remain unclear. Here we utilized primary SSc patient lung cells for high-throughput screening of TGF-β signaling via high-content imaging of nuclear translocation of the profibrotic transcription factor SMAD family member 2/3 (SMAD2/3). We screened an library targeting ubiquitin E3 ligases and observed that knockdown of the E3 ligase Kelch-like protein 42 (KLHL42) impairs TGF-β-dependent profibrotic signaling. KLHL42 knockdown reduced fibrotic tissue production and decreased TGF-β-mediated SMAD activation. Using unbiased ubiquitin proteomics, we identified phosphatase 2 regulatory subunit B'ϵ (PPP2R5ϵ) as a KLHL42 substrate. Mechanistic experiments validated ubiquitin-mediated control of PPP2R5ϵ stability through KLHL42. PPP2R5ϵ knockdown exacerbated TGF-β-mediated profibrotic signaling, indicating a role of PPP2R5ϵ in SSc. Our findings indicate that the KLHL42-PPP2R5ϵ axis controls profibrotic signaling in SSc lung fibroblasts. We propose that future studies could investigate whether chemical inhibition of KLHL42 may ameliorate profibrotic signaling in SSc. © 2020 Lear et al.

KEYWORDS: E3 ubiquitin ligase, KLHL42, PPP2R5ϵ, high-content imaging, high-throughput screening (HTS), protein degradation, scleroderma, systemic sclerosis, transforming growth factor β (TGF-β), ubiquitylation (ubiquitination)