Cell Cycle Arrest by Transforming Growth Factor β1 Enhances Replication of Respiratory Syncytial Virus in Lung Epithelial Cells

ABSTRACT Respiratory syncytial virus (RSV) is a common respiratory viral infection in children which is associated with immune dysregulation and subsequent induction and exacerbations of asthma. We recently reported that treatment of primary human epithelial cells (PHBE cells) with transforming growth factor β (TGF-β) enhanced RSV replication. Here, we report that the enhancement of RSV replication is mediated by induction of cell cycle arrest. These data were confirmed by using pharmacologic inhibitors of cell cycle progression, which significantly enhanced RSV replication. Our data also showed that RSV infection alone resulted in cell cycle arrest in A549 and PHBE cells. Interestingly, our data showed that RSV infection induced the expression of TGF-β in epithelial cells. Blocking of TGF-β with anti-TGF-β antibody or use of a specific TGF-β receptor signaling inhibitor resulted in rescue of the RSV-induced cell cycle arrest, suggesting an autocrine mechanism. Collectively, our data demonstrate that RSV regulates the cell cycle through TGF-β in order to enhance its replication. These findings identify a novel pathway for upregulation of virus replication and suggest a plausible mechanism for association of RSV with immune dysregulation and asthma.

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The MicroRNA 424/503 Cluster Reduces CDC25A Expression during Cell Cycle Arrest Imposed by Transforming Growth Factor in Mammary Epithelial Cells

Molecular and Cellular Biology ◽

10.1128/mcb.00611-14 ◽

2014 ◽

Vol 34 (23) ◽

pp. 4216-4231 ◽

Cited By ~ 27

Author(s):

D. Llobet-Navas ◽

R. Rodriguez-Barrueco ◽

J. de la Iglesia-Vicente ◽

M. Olivan ◽

V. Castro ◽

...

Keyword(s):

Cell Cycle ◽

Growth Factor ◽

Epithelial Cells ◽

Cell Cycle Arrest ◽

Transforming Growth Factor ◽

Mammary Epithelial Cells ◽

Mammary Epithelial ◽

Cycle Arrest

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Respiratory Syncytial Virus Infection Induces Chromatin Remodeling to Activate Growth Factor and Extracellular Matrix Secretion Pathways

Viruses ◽

10.3390/v12080804 ◽

2020 ◽

Vol 12 (8) ◽

pp. 804 ◽

Cited By ~ 1

Author(s):

Xiaofang Xu ◽

Dianhua Qiao ◽

Morgan Mann ◽

Roberto P. Garofalo ◽

Allan R. Brasier

Keyword(s):

Extracellular Matrix ◽

Respiratory Syncytial Virus ◽

Growth Factor ◽

Epithelial Cells ◽

Expression Profiles ◽

Open Chromatin ◽

High Confidence ◽

Chromatin Domains ◽

Rsv Infection ◽

Syncytial Virus

Lower respiratory tract infection (LRTI) with respiratory syncytial virus (RSV) is associated with reduced lung function through unclear mechanisms. In this study, we test the hypothesis that RSV infection induces genomic reprogramming of extracellular matrix remodeling pathways. For this purpose, we sought to identify transcriptionally active open chromatin domains using assay for transposase-accessible-next generation sequencing (ATAC-Seq) in highly differentiated lower airway epithelial cells. High confidence nucleosome-free regions were those predicted independently using two peak-calling algorithms. In uninfected cells, ~12,650 high-confidence open chromatin regions were identified. These mapped to ~8700 gene bodies, whose genes functionally controlled organelle synthesis and Th2 pathways (IL6, TSLP). These latter cytokines are preferentially secreted by RSV-infected bronchiolar cells and linked to mucous production, obstruction, and atopy. By contrast, in RSV infection, we identify ~1700 high confidence open chromatin domains formed in 1120 genes, primarily in introns. These induced chromatin modifications are associated with complex gene expression profiles controlling tyrosine kinase growth factor signaling and extracellular matrix (ECM) secretory pathways. Of these, RSV induces formation of nucleosome-free regions on TGFB1/JUNB//FN1/MMP9 genes and the rate limiting enzyme in the hexosamine biosynthetic pathway (HBP), Glutamine-Fructose-6-Phosphate Transaminase 2 (GFPT2). RSV-induced open chromatin domains are highly enriched in AP1 binding motifs and overlap experimentally determined JUN peaks in GEO ChIP-Seq data sets. Our results provide a topographical map of chromatin accessibility and suggest a growth factor and AP1-dependent mechanism for upregulation of the HBP and ECM remodeling in lower epithelial cells that may be linked to long-term airway remodeling.

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FOXO1 transcription factor regulates chondrogenic differentiation through transforming growth factor β1 signaling

Journal of Biological Chemistry ◽

10.1074/jbc.ra119.009409 ◽

2019 ◽

Vol 294 (46) ◽

pp. 17555-17569 ◽

Cited By ~ 3

Author(s):

Ichiro Kurakazu ◽

Yukio Akasaki ◽

Mitsumasa Hayashida ◽

Hidetoshi Tsushima ◽

Norio Goto ◽

...

Keyword(s):

Cell Cycle ◽

Growth Factor ◽

Cell Cycle Arrest ◽

Chondrogenic Differentiation ◽

Transforming Growth Factor ◽

Human Mesenchymal Stem Cells ◽

Type Ii Collagen ◽

Transforming Growth Factor Β1 ◽

Type Ii ◽

Cycle Arrest

The forkhead box O (FOXO) proteins are transcription factors involved in the differentiation of many cell types. Type II collagen (Col2) Cre-Foxo1-knockout and Col2-Cre-Foxo1,3,4 triple-knockout mice exhibit growth plate malformation. Moreover, recent studies have reported that in some cells, the expressions and activities of FOXOs are promoted by transforming growth factor β1 (TGFβ1), a growth factor playing a key role in chondrogenic differentiation. Here, using a murine chondrogenic cell line (ATDC5), mouse embryos, and human mesenchymal stem cells, we report the mechanisms by which FOXOs affect chondrogenic differentiation. FOXO1 expression increased along with chondrogenic differentiation, and FOXO1 inhibition suppressed chondrogenic differentiation. TGFβ1/SMAD signaling promoted expression and activity of FOXO1. In ATDC5, FOXO1 knockdown suppressed expression of sex-determining region Y box 9 (Sox9), a master regulator of chondrogenic differentiation, resulting in decreased collagen type II α1 (Col2a1) and aggrecan (Acan) expression after TGFβ1 treatment. On the other hand, chemical FOXO1 inhibition suppressed Col2a1 and Acan expression without suppressing Sox9. To investigate the effects of FOXO1 on chondrogenic differentiation independently of SOX9, we examined FOXO1's effects on the cell cycle. FOXO1 inhibition suppressed expression of p21 and cell-cycle arrest in G0/G1 phase. Conversely, FOXO1 overexpression promoted expression of p21 and cell-cycle arrest. FOXO1 inhibition suppressed expression of nascent p21 RNA by TGFβ1, and FOXO1 bound the p21 promoter. p21 inhibition suppressed expression of Col2a1 and Acan during chondrogenic differentiation. These results suggest that FOXO1 is necessary for not only SOX9 expression, but also cell-cycle arrest during chondrogenic differentiation via TGFβ1 signaling.

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