Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation,...Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.展开更多
Interferon regulatory factor 1(IRF-1)is a member of the IRF family.It is the first transcription factor to be identified that could bind to the interferon-stimulated response element(ISRE)on the target gene and displa...Interferon regulatory factor 1(IRF-1)is a member of the IRF family.It is the first transcription factor to be identified that could bind to the interferon-stimulated response element(ISRE)on the target gene and displays crucial roles in the interferoninduced signals and pathways.IRF-1,as an important medium,has all of the advantages of full cell cycle regulation,cell death signaling transduction,and reinforcing immune surveillance,which are well documented.Current studies indicate that IRF-1 is of vital importance to the occurrence and evolution of multifarious liver diseases,including but not limited to inhibiting the replication of the hepatitis virus(A/B/C/E),alleviating the progression of liver fibrosis,and aggravating hepatic ischemiareperfusion injury(HIRI).The tumor suppression of IRF-1 is related to the clinical characteristics of liver cancer patients,which makes it a potential indicator for predicting the prognosis and recurrence of liver cancer;additionally,the latest studies have revealed other effects of IRF-1 such as protection against alcoholic/non-alcoholic fatty liver disease(AFLD/NAFLD),cholangiocarcinoma suppression,and uncommon traits in other liver diseases that had previously received little attention.Intriguingly,several compounds and drugs have featured a protective function in specific liver disease models in which there is significant involvement of the IRF-1 signal.In this paper,we hope to propose a prospective research basis upon which to help decipher translational medicine applications of IRF-1 in liver disease treatment.展开更多
Poly(ADP-ribose) polymerase 1 (PARP1) plays important roles in the regulation of transcription factors. Mounting evidence has shown that inhibition of PARP1 influences the expression of genes associated with inflammat...Poly(ADP-ribose) polymerase 1 (PARP1) plays important roles in the regulation of transcription factors. Mounting evidence has shown that inhibition of PARP1 influences the expression of genes associated with inflammatory response. Interferon regulatory factor 1 (IRF1) is a critical transcription factor for the development of both the innate and adaptive immune responses against infections. However, the molecular mechanism through which PARP1 mediates the effects has not been clearly demonstrated. Jurkat cells were exposed to dexamethasone (Dex) or PARP1 inhibitor PJ34. The expression levels of IL-12, LMP2, OAS1 and PKR were detected using real-time RT-PCR. The interactions between PARP1 and IRF1 were examined by coimmunoprecipitation (co-IP) assays. We further explored the mechanism of PARP1 suppressing IRF1 by assessing the activities of interferon stimulated response element (ISRE). The mRNA expression of IL-12, LMP2, OAS1 and PKR was obviously suppressed by Dex in Jurkat cells, which could be rescued by PJ34 treatment. Luciferase study revealed that poly(ADP-ribosyl)- ation suppressed IRF1-mediated transcription through preventing the binding of IRF1 to ISREs. PARP1 inhibited IRF1-mediated transcription in Jurkat cells by preventing IRF1 binding to ISREs in the promoters of target genes. It is suggested that PARP1 is a crucial regulator of IRF1-mediated immune response. This study provides experimental evidence for the possible application of PARP1 inhibitors in the treatment of IRF1-related immune anergy.展开更多
目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STA...目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STAT的细胞因子信号抑制因子1(SOCS1)和SOCS3的转录水平;Real time PCR检测CNE2细胞干扰素调节因子-1(IRF-1)的转录情况。结果在NaB作用下,CNE2细胞内IDO的表达减少,并且IFN-γ诱导的IDO表达也被显著抑制;SOCS1和SOCS3的转录水平未见改变;而IFN-γ诱导的IRF1转录受到NaB的显著抑制。结论 NaB抑制IFN-γ诱导的IDO表达,不是通过增加SOCS1和SOCS3的转录,而可能是通过下调IRF-1,抑制IFN-γ诱导的IDO表达。展开更多
文摘Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.
基金supported by the Tianjin Natural Science Foundation(No.19JCZDJC36000)the National Natural Science Foundation of China(No.82241219)+1 种基金the National Major Scientific Research Instrument Development Project of China(No.82127808)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.81921004).
文摘Interferon regulatory factor 1(IRF-1)is a member of the IRF family.It is the first transcription factor to be identified that could bind to the interferon-stimulated response element(ISRE)on the target gene and displays crucial roles in the interferoninduced signals and pathways.IRF-1,as an important medium,has all of the advantages of full cell cycle regulation,cell death signaling transduction,and reinforcing immune surveillance,which are well documented.Current studies indicate that IRF-1 is of vital importance to the occurrence and evolution of multifarious liver diseases,including but not limited to inhibiting the replication of the hepatitis virus(A/B/C/E),alleviating the progression of liver fibrosis,and aggravating hepatic ischemiareperfusion injury(HIRI).The tumor suppression of IRF-1 is related to the clinical characteristics of liver cancer patients,which makes it a potential indicator for predicting the prognosis and recurrence of liver cancer;additionally,the latest studies have revealed other effects of IRF-1 such as protection against alcoholic/non-alcoholic fatty liver disease(AFLD/NAFLD),cholangiocarcinoma suppression,and uncommon traits in other liver diseases that had previously received little attention.Intriguingly,several compounds and drugs have featured a protective function in specific liver disease models in which there is significant involvement of the IRF-1 signal.In this paper,we hope to propose a prospective research basis upon which to help decipher translational medicine applications of IRF-1 in liver disease treatment.
基金This work was supported by the National Natural Science Foundation of China (No.81370263 and No.81500348).
文摘Poly(ADP-ribose) polymerase 1 (PARP1) plays important roles in the regulation of transcription factors. Mounting evidence has shown that inhibition of PARP1 influences the expression of genes associated with inflammatory response. Interferon regulatory factor 1 (IRF1) is a critical transcription factor for the development of both the innate and adaptive immune responses against infections. However, the molecular mechanism through which PARP1 mediates the effects has not been clearly demonstrated. Jurkat cells were exposed to dexamethasone (Dex) or PARP1 inhibitor PJ34. The expression levels of IL-12, LMP2, OAS1 and PKR were detected using real-time RT-PCR. The interactions between PARP1 and IRF1 were examined by coimmunoprecipitation (co-IP) assays. We further explored the mechanism of PARP1 suppressing IRF1 by assessing the activities of interferon stimulated response element (ISRE). The mRNA expression of IL-12, LMP2, OAS1 and PKR was obviously suppressed by Dex in Jurkat cells, which could be rescued by PJ34 treatment. Luciferase study revealed that poly(ADP-ribosyl)- ation suppressed IRF1-mediated transcription through preventing the binding of IRF1 to ISREs. PARP1 inhibited IRF1-mediated transcription in Jurkat cells by preventing IRF1 binding to ISREs in the promoters of target genes. It is suggested that PARP1 is a crucial regulator of IRF1-mediated immune response. This study provides experimental evidence for the possible application of PARP1 inhibitors in the treatment of IRF1-related immune anergy.
文摘目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STAT的细胞因子信号抑制因子1(SOCS1)和SOCS3的转录水平;Real time PCR检测CNE2细胞干扰素调节因子-1(IRF-1)的转录情况。结果在NaB作用下,CNE2细胞内IDO的表达减少,并且IFN-γ诱导的IDO表达也被显著抑制;SOCS1和SOCS3的转录水平未见改变;而IFN-γ诱导的IRF1转录受到NaB的显著抑制。结论 NaB抑制IFN-γ诱导的IDO表达,不是通过增加SOCS1和SOCS3的转录,而可能是通过下调IRF-1,抑制IFN-γ诱导的IDO表达。
