Mechanisms and roles by which IRF-3 mediates the regulation of ORMDL3 transcription in respiratory syncytial virus infection.
Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis in infancy, which is a major risk factor for recurrent wheezing and asthma. Orosomucoid 1-like protein 3 (ORMDL3) has been reported to associate with virus-triggered recurrent wheezing and asthma in children. However, little is known about how ORMDL3 is involved into RSV infection. In this study, we showed that the mRNA expression of ORMDL3 is significantly increased in the peripheral blood lymphocytes of infants with RSV-induced bronchiolitis compared with uninfected controls, also increased in bronchial epithelial cells and lung fibroblasts following RSV infection in vitro. To investigate the underlying mechanisms of RSV-induced ORMDL3 expression, we performed in silico analysis of the binding sites of several transcription factors in the ORMDL3 promoter. The proximal interferon-regulatory factor-3 (IRF-3) binding site positively regulated ORMDL3 transcription following exposure to RSV, as determined through mutational analysis. Overexpression and RNA interference experiments targeting IRF-3 showed that it regulates the expression of ORMDL3 following RSV exposure. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay showed that IRF-3 binds directly to the promoter of the ORMDL3 gene. Furthermore, we confirmed that expression of IRF-3 is significantly increased and shows a strong linear correlation with increased ORMDL3 in the peripheral blood lymphocytes from infants with RSV-induced bronchiolitis. Our results indicate that IRF-3 is an important regulator of ORMDL3 induction following RSV infection by binding directly to the promoter of ORMDL3, which may be implicated in the inflammatory and immune reactions involved in bronchiolitis and wheezing diseases.
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China; Department of Pediatrics, Nanjing First Hospital, Nanjing Medical University, 68 Chang Le Road, Nanjing, Jiangsu Province 210006, China.
Xiao-Hua
XH
Wang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Jin
J
Shu
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Chun-Ming
CM
Jiang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Li-Li
LL
Zhuang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Wei-Xia
WX
Yang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Hui-Weng
HW
Zhang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Lu-Lu
LL
Wang
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Lin
L
Li
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China.
Xiao-Qing
XQ
Chen
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China. Electronic address: jr8622@163.com.
Rui
R
Jin
Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, 300 Guang Zhou Road, Nanjing, Jiangsu Province 210029, China. Electronic address: guopzhou@126.com.
Guo-Ping
GP
Zhou
D001988:Bronchiolitis / Q000150:complications; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007223:Infant; D050838:Interferon Regulatory Factor-3 / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D018357:Respiratory Syncytial Virus Infections / Q000150:complications / Q000235:genetics* / Q000378:metabolism*; D012136:Respiratory Syncytial Viruses / Q000502:physiology*; D014158:Transcription, Genetic
C494232:IRF3 protein, human; D050838:Interferon Regulatory Factor-3; D008565:Membrane Proteins; C464399:ORMDL3 protein, human
Bronchiolitis; Interferon-regulatory factor-3 (IRF-3); Orosomucoid 1-like protein 3 (ORMDL3); Respiratory syncytial virus (RSV); Transcriptional regulation