三重基序蛋白25(Tripartite motif-containing protein 25,TRIM25)属于E3泛素连接酶家族,在先天免疫反应中发挥重要作用。为研究TRIM25基因在大黄鱼(Larimichthys crocea)先天抗病毒免疫反应中的作用,研究鉴定并克隆大黄鱼TRIM25基因(...三重基序蛋白25(Tripartite motif-containing protein 25,TRIM25)属于E3泛素连接酶家族,在先天免疫反应中发挥重要作用。为研究TRIM25基因在大黄鱼(Larimichthys crocea)先天抗病毒免疫反应中的作用,研究鉴定并克隆大黄鱼TRIM25基因(命名为LcTRIM25)。LcTRIM25基因编码序列2097 bp(GenBank登录号:MK327541),编码698个氨基酸。蛋白结构域预测发现LcTRIM25包括保守的RING结构域、B-box2结构域、Coiled-coil结构域和可变的C末端PRY/SPRY结构域。多序列比对以及系统进化树分析表明LcTRIM25基因与斜带石斑鱼同源性高,与哺乳动物、爬行动物、两栖动物和鸟类同源性相对低,这说明不同物种受到来自环境不同的选择压力,导致进化程度不同。应用实时荧光定量PCR方法分析大黄鱼TRIM25基因的表达水平。结果分析发现LcTRIM25基因在健康大黄鱼的9个组织中均有广泛表达,且在肝脏中表达量最高,在心脏中表达量最低。在poly(I:C)刺激后,在外周血、头肾、脾脏和肝脏中LcTRIM25基因表达量迅速且明显上调,均出现上升达到峰值后下降的趋势。LcTRIM25基因表达量在头肾和脾脏中6h达到最高表达量,在肝脏中12h达到峰值,外周血中在24h达到最高表达量。上述结果表明,不同组织中LcTRIM25基因表达模式具有差异性。研究结果推测大黄鱼TRIM25基因参与抗病毒免疫反应且发挥十分关键的作用,为进一步了解大黄鱼抗病毒免疫机制提供理论基础。展开更多
Enteroviruses(EVs) 3C proteins suppress type I interferon(IFN) responses mediated by retinoid acid-inducible gene I(RIG-I), while an E3 ubiquitin ligase, tripartite motif protein 25(TRIM25)-mediated RIG-I ubiquitinati...Enteroviruses(EVs) 3C proteins suppress type I interferon(IFN) responses mediated by retinoid acid-inducible gene I(RIG-I), while an E3 ubiquitin ligase, tripartite motif protein 25(TRIM25)-mediated RIG-I ubiquitination is essential for RIG-I antiviral activity. Therefore, whether the effect of EVs 3C on RIG-I is associated with TRIM25 expression is worth to be further investigated. Here, we demonstrate that 3C proteins of EV71 and coxsackievirus B3(CVB3) reduced not only RIG-I expression but also TRIM25 expression through protease cleavage activity, while overexpression of TRIM25 restored RIG-I expression and IFN-b production reduced by 3C proteins. Further investigation confirmed that the two amino acids and functional domains in TRIM25 required for RIG-I ubiquitination and TRIM25 structural conformation were essential for the recovery of RIG-I expression. Moreover, we also observed that TRIM25 could rescue RIG-I expression reduced by 3C proteins of CVA6 and EV-D68 but not CVA16. Our findings provide an insightful interpretation of 3C-mediated host innate immune suppression and support TRIM25 as an attractive target against multiple EVs infection.展开更多
TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzym...TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzyme for ubiquitin;and(3)TRIM25 is also an E3 ligase for interferon-stimulated gene 15 protein in the ISGylation system.Consequently,the proteome of mammary tissue is affected by TRIM25-associated pathways,involved in tumor development and metastasis.Here,we discuss the findings on the mechanisms involved in regulating TRIM25 expression and its functional relevance in breast cancer progression.These studies suggest that TRIM25 may be a biomarker and a therapeutic target for breast cancer.展开更多
The productive infection of influenza A virus(IAV)requires the functional involvement of host long noncoding ribonucleic acids(lncRNAs).Identification of key cellular lncRNAs and elucidation of their molecular mechani...The productive infection of influenza A virus(IAV)requires the functional involvement of host long noncoding ribonucleic acids(lncRNAs).Identification of key cellular lncRNAs and elucidation of their molecular mechanisms in IAV replication are expected to expand our understanding of virus-host interactions and develop antiviral therapeutics.Our previous work has identified that influenza virus polymerase basic protein 1(PB1)-associated long noncoding RNA(IPAN)associates with and stabilizes viral RNA-dependent RNA polymerase PB1 of IAV,warranting efficient viral RNA synthesis.This provides a unique viral strategy of co-opting host lncRNA for replication,whereas the molecular pathways exploited by the virus are unknown.Here,we aim to further investigate the detailed mechanisms underlying IPAN-mediated PB1 stabilization.We employed cellular-level molecular interaction techniques to demonstrate that both retinoic acid-inducible gene I(RIG-I)and tripartite motif-containing protein 25(TRIM25)interacted with PB1 and co-operated to induce its degradation triggered by viral RNA synthesis.The experimental data obtained from RIG-I knockout cell lines and mutational analyses demonstrated RIG-I promoted PB1 degradation independently of its canonical signaling pathway,suggesting an“effector-like”antiviral activity of RIG-I.Furthermore,IPAN knockdown enhanced the association of PB1 with both RIG-I and TRIM25 to restore PB1 stability.These results collectively demonstrated that IAV hijacked host IPAN to protect PB1 from RIG-I/TRIM25-mediated antiviral degradation.Thus,our data reveal a mechanism of RIG-I and TRIM25 against IAV infection by degrading PB1 and highlight how IAV exploits host lncRNAs to evade immune surveillance.展开更多
基金The study was supported by the National Natural Science Foundation of China(No.81672004 and 81930062)the Science and Technology Department of Jilin Province(20190101003JH)the Key Laboratory of Molecular Virology,Jilin Province(20102209)。
文摘Enteroviruses(EVs) 3C proteins suppress type I interferon(IFN) responses mediated by retinoid acid-inducible gene I(RIG-I), while an E3 ubiquitin ligase, tripartite motif protein 25(TRIM25)-mediated RIG-I ubiquitination is essential for RIG-I antiviral activity. Therefore, whether the effect of EVs 3C on RIG-I is associated with TRIM25 expression is worth to be further investigated. Here, we demonstrate that 3C proteins of EV71 and coxsackievirus B3(CVB3) reduced not only RIG-I expression but also TRIM25 expression through protease cleavage activity, while overexpression of TRIM25 restored RIG-I expression and IFN-b production reduced by 3C proteins. Further investigation confirmed that the two amino acids and functional domains in TRIM25 required for RIG-I ubiquitination and TRIM25 structural conformation were essential for the recovery of RIG-I expression. Moreover, we also observed that TRIM25 could rescue RIG-I expression reduced by 3C proteins of CVA6 and EV-D68 but not CVA16. Our findings provide an insightful interpretation of 3C-mediated host innate immune suppression and support TRIM25 as an attractive target against multiple EVs infection.
文摘TRIM25 is emerging as a central factor in breast cancer due to its regulation and function.In particular,it has been shown that:(1)Estrogens modulate TRIM25 gene expression;(2)TRIM25 has activity as an E3-ligase enzyme for ubiquitin;and(3)TRIM25 is also an E3 ligase for interferon-stimulated gene 15 protein in the ISGylation system.Consequently,the proteome of mammary tissue is affected by TRIM25-associated pathways,involved in tumor development and metastasis.Here,we discuss the findings on the mechanisms involved in regulating TRIM25 expression and its functional relevance in breast cancer progression.These studies suggest that TRIM25 may be a biomarker and a therapeutic target for breast cancer.
基金supported by Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2021-I2M-1-038,2022-I2M-2-002)National Natural Science Foundation of China(81971950)+2 种基金Natural Science Foundation of Shandong Province(ZR2022QH321)the National Microbial Resource Center(NMRC-2020-3)the CAMS Collection Center of Pathogenic Microorganisms(CAMS-CCPM-A)for providing valuable reagents.
文摘The productive infection of influenza A virus(IAV)requires the functional involvement of host long noncoding ribonucleic acids(lncRNAs).Identification of key cellular lncRNAs and elucidation of their molecular mechanisms in IAV replication are expected to expand our understanding of virus-host interactions and develop antiviral therapeutics.Our previous work has identified that influenza virus polymerase basic protein 1(PB1)-associated long noncoding RNA(IPAN)associates with and stabilizes viral RNA-dependent RNA polymerase PB1 of IAV,warranting efficient viral RNA synthesis.This provides a unique viral strategy of co-opting host lncRNA for replication,whereas the molecular pathways exploited by the virus are unknown.Here,we aim to further investigate the detailed mechanisms underlying IPAN-mediated PB1 stabilization.We employed cellular-level molecular interaction techniques to demonstrate that both retinoic acid-inducible gene I(RIG-I)and tripartite motif-containing protein 25(TRIM25)interacted with PB1 and co-operated to induce its degradation triggered by viral RNA synthesis.The experimental data obtained from RIG-I knockout cell lines and mutational analyses demonstrated RIG-I promoted PB1 degradation independently of its canonical signaling pathway,suggesting an“effector-like”antiviral activity of RIG-I.Furthermore,IPAN knockdown enhanced the association of PB1 with both RIG-I and TRIM25 to restore PB1 stability.These results collectively demonstrated that IAV hijacked host IPAN to protect PB1 from RIG-I/TRIM25-mediated antiviral degradation.Thus,our data reveal a mechanism of RIG-I and TRIM25 against IAV infection by degrading PB1 and highlight how IAV exploits host lncRNAs to evade immune surveillance.
