Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of ...Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of tumors.Previous reports have indicated the involvement of both METTL3 and c-Src kinase in the evolution of liver cancer.However,the potential connection between c-Src and the METTL3-mediated mechanism in liver cancer progression remains elusive.Methods:The correlation expression between c-Src and METTL3 between liver cancer patients and the control group was analyzed using the TCGA database,and was further demonstrated by Western blot and RT-qPCR.The functional roles of c-Src in METTL3-regulated liver cancer progression were investigated by cell proliferation assays and colony formation assays.The regulatory mechanism of METTL3 in c-Src expression was accessed by RNA-immunoprecipitation(RIP)-qPCR.Results:We demonstrated that c-Src kinase promoted liver cancer development,and the expression of SRC(encodes c-Src kinase)was positively correlated with METTL3 in liver cancer cases.We showed that SRC mRNA could be m6A-modified,and METTL3 regulated the transcription of SRC mRNA through interferon regulatory factor 1(IRF1).We revealed that IRF1,the expression of which was positively regulated byMETTL3,was a novel transcription factor of c-Src.Lastly,The pro-proliferative effect of METTL3 on hepatocellular carcinoma was mechanistically linked to IRF1/c-Src axis activation,as evidenced by our experimental data.Conclusion:Results suggested that the METTL3/IRF1/c-Src axis played potential oncogenic roles in liver cancer development and the axis may be a promising therapeutic target in the disease.展开更多
The key role of structural cells in immune modulation has been revealed with the advent of single-cell multiomics,but the underlying mechanism remains poorly understood.Here,we revealed that the transcriptional activa...The key role of structural cells in immune modulation has been revealed with the advent of single-cell multiomics,but the underlying mechanism remains poorly understood.Here,we revealed that the transcriptional activation of interferon regulatory factor 1(IRF1)in response to ionizing radiation,cytotoxic chemicals and SARS-CoV-2 viral infection determines the fate of structural cells and regulates communication between structural and immune cells.Radiation-induced leakage of mtDNA initiates the nuclear translocation of IRF1,enabling it to regulate the transcription of inflammation-and cell death-related genes.Novel posttranslational modification(PTM)sites in the nuclear localization sequence(NLS)of IRF1 were identified.Functional analysis revealed that mutation of the acetylation site and the phosphorylation sites in the NLS blocked the transcriptional activation of IRF1 and reduced cell death in response to ionizing radiation.Mechanistically,reciprocal regulation between the single-stranded DNA sensors SSBP1 and IRF1,which restrains radiation-induced and STING/p300-mediated PTMs of IRF1,was revealed.In addition,genetic deletion or pharmacological inhibition of IRF1 tempered radiation-induced inflammatory cell death,and radiation mitigators also suppressed SARS-CoV-2 NSP-10-mediated activation of IRF1.Thus,we revealed a novel cytoplasm-oriented mechanism of IRF1 activation in structural cells that promotes inflammation and highlighted the potential effectiveness of IRF1 inhibitors against immune disorders.展开更多
基金supported by Natural Science Foundation of Hunan Province of China(project No.2022JJ40413)Outstanding Youth Project of Hunan Provincial Department of Education(project No.22B0814)+1 种基金Regional Consolidated Foundation ofHunan Province of China(project No.2023JJ50065)Natural Science Foundation of Hunan Province of China(project No.2023JJ50412).
文摘Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of tumors.Previous reports have indicated the involvement of both METTL3 and c-Src kinase in the evolution of liver cancer.However,the potential connection between c-Src and the METTL3-mediated mechanism in liver cancer progression remains elusive.Methods:The correlation expression between c-Src and METTL3 between liver cancer patients and the control group was analyzed using the TCGA database,and was further demonstrated by Western blot and RT-qPCR.The functional roles of c-Src in METTL3-regulated liver cancer progression were investigated by cell proliferation assays and colony formation assays.The regulatory mechanism of METTL3 in c-Src expression was accessed by RNA-immunoprecipitation(RIP)-qPCR.Results:We demonstrated that c-Src kinase promoted liver cancer development,and the expression of SRC(encodes c-Src kinase)was positively correlated with METTL3 in liver cancer cases.We showed that SRC mRNA could be m6A-modified,and METTL3 regulated the transcription of SRC mRNA through interferon regulatory factor 1(IRF1).We revealed that IRF1,the expression of which was positively regulated byMETTL3,was a novel transcription factor of c-Src.Lastly,The pro-proliferative effect of METTL3 on hepatocellular carcinoma was mechanistically linked to IRF1/c-Src axis activation,as evidenced by our experimental data.Conclusion:Results suggested that the METTL3/IRF1/c-Src axis played potential oncogenic roles in liver cancer development and the axis may be a promising therapeutic target in the disease.
基金National Natural Science Foundation of China 82073477(SZ),32071238(DY)and 82203973(FG)Scientific Fund for Distinguished Young Scholars in Sichuan Province 2022JDJQ0051(SZ)and 2022NSFSC0797(CS)and Young Talent Project of China National Nuclear Corporation(SZ).
文摘The key role of structural cells in immune modulation has been revealed with the advent of single-cell multiomics,but the underlying mechanism remains poorly understood.Here,we revealed that the transcriptional activation of interferon regulatory factor 1(IRF1)in response to ionizing radiation,cytotoxic chemicals and SARS-CoV-2 viral infection determines the fate of structural cells and regulates communication between structural and immune cells.Radiation-induced leakage of mtDNA initiates the nuclear translocation of IRF1,enabling it to regulate the transcription of inflammation-and cell death-related genes.Novel posttranslational modification(PTM)sites in the nuclear localization sequence(NLS)of IRF1 were identified.Functional analysis revealed that mutation of the acetylation site and the phosphorylation sites in the NLS blocked the transcriptional activation of IRF1 and reduced cell death in response to ionizing radiation.Mechanistically,reciprocal regulation between the single-stranded DNA sensors SSBP1 and IRF1,which restrains radiation-induced and STING/p300-mediated PTMs of IRF1,was revealed.In addition,genetic deletion or pharmacological inhibition of IRF1 tempered radiation-induced inflammatory cell death,and radiation mitigators also suppressed SARS-CoV-2 NSP-10-mediated activation of IRF1.Thus,we revealed a novel cytoplasm-oriented mechanism of IRF1 activation in structural cells that promotes inflammation and highlighted the potential effectiveness of IRF1 inhibitors against immune disorders.
