Regulator of G protein signaling (RGS) proteins are united into a family by the presence of the homologous RGS domain that binds the alpha subunits of heterotrimeric G proteins and accelerates their GTPase activity. A member of this family, RGS3 regulates the signaling mediated by G(q) and G(i) proteins by binding the corresponding Galpha subunits. Here we show that RGS3 interacts with the novel partners Smad2, Smad3, and Smad4-the transcription factors that are activated through a transforming growth factor-beta (TGF-beta) receptor signaling. This interaction is mediated by the region of RGS3 outside of the RGS domain and by Smad's Mad homology 2 domain. Overexpression of RGS3 results in inhibition of Smad-mediated gene transcription. RGS3 does not affect TGF-beta-induced Smad phosphorylation, but it prevents heteromerization of Smad3 with Smad4, which is required for transcriptional activity of Smads. This translates to functional inhibition of TGF-beta-induced myofibroblast differentiation by RGS3. In conclusion, this study identifies a novel, noncanonical role of RGS3 in regulation of TGF-beta signaling through its interaction with Smads and interfering with Smad heteromerization.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3329871 | PMC |
http://dx.doi.org/10.1124/mol.108.044990 | DOI Listing |
Biofactors
June 2024
Department of Marine Life Science, Jeju National University, Jeju, Republic of Korea.
Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition characterized by the abnormal regulation of extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT). In this study, we investigated the potential of rutin, a natural flavonoid, in attenuating transforming growth factor-β (TGF-β)-induced ECM regulation and EMT through the inhibition of the TGF-β type I receptor (TβRI)-mediated suppressor of mothers against decapentaplegic (SMAD) signaling pathway. We found that non-toxic concentrations of rutin attenuated TGF-β-induced ECM-related genes, including fibronectin, elastin, collagen 1 type 1, and TGF-β, as well as myoblast differentiation from MRC-5 lung fibroblast cells accompanied by the downregulation of α-smooth muscle actin.
View Article and Find Full Text PDFJ Tradit Chin Med
October 2023
10 Department of Rehabilitation, the First Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine, and Traditional Chinese Medicine Informatics Key Laboratory of Heilongjiang Province, Harbin 150040, China.
Objective: To observe the efficacy of moxibustion in the treatment of chronic fatigue syndrome (CFS) and explore the effects on gut microbiota and metabolic profiles.
Methods: Forty-eight male Sprague-Dawley rats were randomly assigned to control group (Con), CFS model group (Mod, established by multiple chronic stress for 35 d), MoxA group (CFS model with moxibustion Shenque (CV8) and Guanyuan (CV4), 10 min/d, 28 d) and MoxB group (CFS model with moxibustion Zusanli (ST36), 10 min/d, 28 d). Open-field test (OFT) and Morris-water-maze test (MWMT) were determined for assessment the CFS model and the therapeutic effects of moxibustion.
Lab Invest
February 2023
Department of Nephrology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, People's Republic of China. Electronic address:
Renal fibrosis is the major pathologic manifestation of chronic kidney disease (CKD). LIM and cysteine-rich domains 1 (LMCD1) is upregulated in the kidney tissue from patients with CKD and the transforming growth factor β1 (TGF-β1)-treated human renal tubular epithelial cell line human kidney 2 (HK-2) (Gene Expression Omnibus: GSE66494 and GSE23338). Previously, we have demonstrated that the knockdown of LMCD1 ameliorated renal fibrosis in mice by blocking the activation of the extracellular signal-regulated kinase pathway.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2023
Department of Biology, Technical University Darmstadt, 64287 Darmstadt, Germany.
SMAD-mediated signaling regulates apoptosis, cell cycle arrest, and epithelial-to-mesenchymal transition to safeguard tissue homeostasis. However, it remains elusive how the relatively simple pathway can determine such a broad range of cell fate decisions and how it differentiates between varying ligands. Here, we systematically investigate how SMAD-mediated responses are modulated by various ligands of the transforming growth factor β (TGFβ) family and compare these ligand responses in quiescent and proliferating MCF10A cells.
View Article and Find Full Text PDFAdv Cancer Res
August 2022
The Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, United States; Department of Medicine, Division of Gastroenterology and Hepatology, Northwell Health, New Hyde Park, NY, United States; Center for Translational Medicine, Department of Surgery, The George Washington University, Washington, DC, United States. Electronic address:
Despite progress in treating or preventing viral hepatitis, a leading cause of liver cancer, hepatocellular cancer (HCC) continues to be a major cause of cancer-related deaths globally. HCC is a highly heterogeneous cancer with many genetic alterations common within a patient's tumor and between different patients. This complicates therapeutic strategies.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!