RRC ID 2015
Author Fujii T, Onohara N, Maruyama Y, Tanabe S, Kobayashi H, Fukutomi M, Nagamatsu Y, Nishihara N, Inoue R, Sumimoto H, Shibasaki F, Nagao T, Nishida M, Kurose H.
Title Galpha12/13-mediated production of reactive oxygen species is critical for angiotensin receptor-induced NFAT activation in cardiac fibroblasts.
Journal J Biol Chem
Abstract Angiotensin II (Ang II) activates multiple signaling pathways leading to hyperplasia of cardiac fibroblasts. Reactive oxygen species (ROS) produced by Ang II stimulation are assumed to play pivotal roles in this process. Here, we show that ROS mediate Ang II-induced activation of nuclear factor of activated T cells (NFAT) in rat cardiac fibroblasts. Ang II-induced NFAT activation was suppressed by diphenyleneiodonium (an NADPH oxidase inhibitor), dominant negative (DN)-Rac, DN-p47(phox), and an inhibitor of Galpha(12/13) (Galpha(12/13)-specific regulator of G protein signaling domain of p115RhoGEF, p115-regulator of G protein signaling (RGS)). Stimulation of Ang II receptor increased the intracellular ROS level in a Rac- and p47(phox)-dependent manner. Because p115-RGS suppressed Ang II-induced Rac activation, Ang II receptor-coupled Galpha(12/13) mediated NFAT activation through ROS production by Rac activation. Ang II-induced nuclear translocation of the green fluorescent protein (GFP)-tagged amino-terminal region of NFAT4 (GFP-NFAT4) was suppressed by p115-RGS or BAPTA but not by diphenyleneiodonium. The expression of constitutively active (CA)-Galpha(12/13), CA-G translocation alpha(13), or CA-Rac increased the nuclear of GFP-NFAT4. These results suggest that NFAT activity is regulated by both Ca(2+)-dependent and ROS-dependent pathways. Furthermore, activation of c-Jun NH(2)-terminal kinase (JNK) induced by Ang II stimulation is required for NFAT activation because Ang II-induced NFAT activation was inhibited by SP600125, a selective JNK inhibitor. These results indicate that Ang II stimulates the nuclear translocation and activation of NFAT by integrated pathways including the activation of Galpha(12/13), Rac, NADPH oxidase, and JNK and that Galpha(12/13)-mediated ROS production is essential for NFAT transcriptional activation.
Volume 280(24)
Pages 23041-7
Published 2005-6-17
DOI 10.1074/jbc.M409397200
PII S0021-9258(20)61477-6
PMID 15826947
MeSH Active Transport, Cell Nucleus Adenoviridae / genetics Angiotensin II / chemistry Animals Anthracenes / pharmacology Blotting, Western Calcium / metabolism Cell Nucleus / metabolism Cells, Cultured DNA-Binding Proteins / metabolism* Enzyme Inhibitors / pharmacology Fibroblasts / metabolism* GTP-Binding Protein alpha Subunits, G12-G13 / metabolism* Genes, Dominant Green Fluorescent Proteins / chemistry Green Fluorescent Proteins / metabolism Heart Ventricles / cytology JNK Mitogen-Activated Protein Kinases / metabolism MAP Kinase Kinase 4 Mitogen-Activated Protein Kinase Kinases / metabolism Models, Biological Models, Chemical Myocardium / metabolism* NADPH Oxidases / metabolism NFATC Transcription Factors Nuclear Proteins / metabolism* Onium Compounds / pharmacology Phosphoproteins / metabolism Phosphorylation Plasmids / metabolism Protein Binding Protein Structure, Tertiary Protein Transport Rats Rats, Sprague-Dawley Reactive Oxygen Species* Receptors, Angiotensin / metabolism* Signal Transduction Time Factors Transcription Factors / metabolism* Transcriptional Activation rac GTP-Binding Proteins / genetics
IF 4.238
Times Cited 71
DNA material AxCALacZ (RDB1745)