| Title | HnRNP A1/A2 and SF2/ASF Regulate Alternative Splicing of Interferon Regulatory Factor-3 and Affect Immunomodulatory Functions in Human Non-Small Cell Lung Cancer Cells |
| Authors | Guo, Rong Li, Yong Ning, Jinying Sun, Dan Lin, Lianjun Liu, Xinmin |
| Affiliation | Peking Univ First Hosp, Dept Geriatr, Beijing 100871, Peoples R China. Beijing Canc Hosp, Peking Univ Canc Hosp, Beijing Inst Canc Res,Dept Lab Anim, Key Lab Carcinogenesis & Translat Res,Minist Educ, Beijing, Peoples R China. Crown Biosci Inc Beijing, Dept Cell Biol, Beijing, Peoples R China. |
| Keywords | GENE-EXPRESSION MESSENGER-RNA HEPATOCELLULAR-CARCINOMA NUCLEAR TRANSLOCATION LINKING INFLAMMATION ACTIVATION IRF-3 TRANSCRIPTION IMMUNITY SURVIVAL |
| Issue Date | 2013 |
| Publisher | plos one |
| Citation | PLOS ONE.2013,8,(4). |
| Abstract | Heterogeneous nuclear ribonucleoparticule A1/A2 (hnRNP A1/A2) and splicing factor 2/alternative splicing factor (SF2/ASF) are pivotal for precursor messenger RNA (pre-mRNA) splicing. Interferon regulatory factor-3 (IRF-3) plays critical roles in host defense against viral and microbial infection. Truncated IRF-3 proteins resulting from alternative splicing have been identified and characterized as functional antagonists to full-length IRF-3. In this study, we examined the molecular mechanism for splicing regulation of IRF-3 pre-mRNA and first reported the regulatory effect of hnRNP A1/A2 and SF2/ASF on IRF-3 splicing and activation. RNA interference-mediated depletion of hnRNP A1/A2 or SF2/ASF in human non-small cell lung cancer (NSCLC) cells increased exclusion of exons 2 and 3 of IRF-3 gene and reduced expression levels of IRF-3 protein and IRF-3 downstream effector molecules interferon-beta and CXCL10/IP-10. In addition, direct binding of hnRNP A1 and SF2/ASF to specific binding motifs in IRF-3 intron 1 was confirmed by RNA electrophoretic mobility shift assay. Subsequent minigene splicing assay showed that IRF-3 minigenes with mutated hnRNPA 1/A2 or SF2/ASF binding motifs increased exclusion of exons 2 and 3. Moreover, knockdown of hnRNP A1/A2 or SF2/ASF in NSCLC cells reinforced phytohemagglutinin-induced tumor necrosis factor-alpha release by peripheral blood mononuclear cells (PBMC) but suppressed that of interleukin-10 in NSCLC/PBMC co-cultures. Taken together, our results suggest that specific knockdown for hnRNP A1/A2 or SF2/ASF increase exclusion of exons 2 and 3 of IRF-3 pre-mRNA and influence immunomodulatory functions of human NSCLC cells. |
| URI | http://hdl.handle.net/20.500.11897/190188 |
| ISSN | 1932-6203 |
| DOI | 10.1371/journal.pone.0062729 |
| Indexed | SCI(E) PubMed |
| Appears in Collections: | 第一医院 北京肿瘤医院 |
