AIM： To investigate the effect of APOBEC3G mediated antiviral activity against hepatitis B virus （HBV） in cell cultures and replication competent HBV vector-based mouse model. METHODS： The mammalian hepatoma cells...AIM： To investigate the effect of APOBEC3G mediated antiviral activity against hepatitis B virus （HBV） in cell cultures and replication competent HBV vector-based mouse model. METHODS： The mammalian hepatoma cells Huh7 and HepG2 were cotransfected with various amounts of CMV-driven expression vector encoding APOBEC3G and replication competent 1.3 fold over-length HBV. Levels of HBsAg and HBeAg in the media of the transfected cells were determined by ELISA. The expression of HBcAg in transfected cells was detected by western blot. HBV DNA and RNA from intracellular core particles were examined by Northern and Southern blot analyses. To assess activity of the APOBEC3G in vivo, an HBV vector-based model was used in which APOBEC3G and the HBV vector were co-delivered via high-volume tail vein injection. Levels of HBsAg and HBV DNA in the sera of mice as well as HBV core-associated RNA in the liver of mice were determined by ELISA and quantitative PCR analysis respectively. RESULTS： There was a dose dependent decrease in the levels of intracellular core-associated HBV DNA and extracellular production of HBsAg and HBeAg. The levels of intracellular core-associated viral RNA also decreased, but the expression of HBcAg in transfected cells showed almost no change. Consistent with in vitro results, levels of HBsAg in the sera of mice were dramatically decreased. More than 1.5 log10 decrease in levels of serum HBV DNA and liver HBV RNA were observed in the APOBEC3G-treated groups compared with the control groups.CONCLUSION： These findings indicate that APOBEC3G could suppress HBV replication and antigen expression both in vivo and in vitro, promising an advance in treatment of HBV infection.展开更多
Interaction between the HIV-1 Vif protein and the cellular host APOBEC3G protein is a promising target for inhibition of HIV-1 replication. Considering that human cells are a very complicated environment for the study...Interaction between the HIV-1 Vif protein and the cellular host APOBEC3G protein is a promising target for inhibition of HIV-1 replication. Considering that human cells are a very complicated environment for the study of protein interactions, the goal of this study was to check whether fission yeast could be used as a model cell for studying the Vif-APOBEC3G interaction. Vif and APOBEC3G were expressed in fusion with GFP protein in the S. pombe SP223 strain. Subcellular localizations of Vif and APOBEC3G were observed with fluorescent microscopy. Codon optimization was used to over express the Vif protein in S. pombe cells. The degradation of APOBEC3G mediated by Vif was tested through expressing Vif and GFP-APOBEC3G proteins in the same cell. Western Blot analysis was used to measure the corresponding protein levels under different experimental conditions. The results showed that the Vif protein was predominantly localized in the nucleus of S. pombe cells, APOBEC3G was localized in the cytoplasm and concentrated at punctate bodies that were often in close proximity to the nucleus but were not necessarily restricted from other regions in the cytoplasm. Vif protein expression levels were increased significantly by using codon optimization and APOBEC3G was degraded when Vif was over-expressed in the same S. pombe cells. These results indicate that fission yeast is a good model for studying the interaction between the Vif and APOBEC3G proteins.展开更多
The highly active antiretroviral treatment (HAART) has allowed people living with HIV to live longer with a better quality of life. However, toxicity and the emergence of drug resistance arise from HAART use. Therefor...The highly active antiretroviral treatment (HAART) has allowed people living with HIV to live longer with a better quality of life. However, toxicity and the emergence of drug resistance arise from HAART use. Therefore, new antiretroviral therapy is needed since no cure or vaccine is available against HIV. Virus-host interaction has been proven to be important in the last decade. Host factors such as the C-C chemokine receptor type 5 (CCR5), a receptor used by HIV to penetrate host cells, have led to the discovery of the Maraviroc, which is an antiretroviral medication used in the United States. In contrast, other factors like C-X-C Motif Chemokine Receptor 4 (CXCR4) and the Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3G (APOBEC3G), a potent host defense factor against HIV, is under investigation. APOBEC3G antiviral activity remains a possible therapeutic target against HIV. This systematic review aimed to synthesize the available evidence on the role of APOBEC3G polymorphisms and their expression on HIV infection disease progression in Africa. We used Web of Science, PubMed, Embase, and Google Scholar and searched for relevant publications in French or English reporting on APOBEC3G polymorphisms association with HIV infection in African populations from January 2009 to May 2023. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyzes) was used to process for reporting systematic review. Fifteen studies were included, of which seven were on APOBEC3G polymorphisms and eight were on APOBEC3G expression. Among the APOBEC3G polymorphisms, the most studied was H186R or rs8177832. The average of the minor allele frequency of H186R of APOBEC3G available for the studies included in this study was 0.29 with a 95% CI (0.172;0.401) and varied from 0.108 reported in Uganda to 0.47 recorded from Burkina Faso. The polymorphism H186R was not associated with HIV status in Southern Africa. However, the referent allele of H186R was protective against HIV infection in Western Central Africa, while in West Africa, it was the minor allele (G) of H186R which was protective against HIV. This review warrants a need to increase research on APOBEC3G, from its variants to its hypermutations on the continent with an essential variety of HIV-1 subtypes, to impact the research on A3G-based anti-HIV strategies.展开更多
载脂蛋白B m RNA编辑酶催化多肽3F(APOBEC3F)属固有免疫系统中的重要成员,对人免疫缺陷病毒(HIV)、乙型肝炎病毒(HBV)等多种病毒的复制具有广泛的抑制作用。为构建APOBEC3F基因的真核表达载体,并检测其在体外培养的MARC145细胞中的表达...载脂蛋白B m RNA编辑酶催化多肽3F(APOBEC3F)属固有免疫系统中的重要成员,对人免疫缺陷病毒(HIV)、乙型肝炎病毒(HBV)等多种病毒的复制具有广泛的抑制作用。为构建APOBEC3F基因的真核表达载体,并检测其在体外培养的MARC145细胞中的表达情况,通过RT-PCR从猪脾脏组织扩增APOBEC3F基因,定向克隆到表达增强型绿色荧光蛋白(EGFP)的真核表达载体p EGFP-CMV中,构建p EGFP-APOBEC3F。PCR扩增及测序显示,APOBEC3F插入载体位置、方向及序列均正确。p EGFP-APOBEC3F经脂质体介导法转染MARC145细胞,转染后24 h APOBEC3F m RNA的水平升至最高。细胞免疫化学法检测发现APOBEC3F蛋白主要在MARC145细胞质中表达。研究结果为体外研究猪APOBEC3F基因在抗猪蓝耳病中的作用奠定了基础。展开更多
To clarify the role of APOBEC3G （A3G） in cellular defense against hepatitis B virus （HBV）, the expression of A3G in normal human liver and the regulation of the A3G expression in hepatoma cell line （HuH-7） were ...To clarify the role of APOBEC3G （A3G） in cellular defense against hepatitis B virus （HBV）, the expression of A3G in normal human liver and the regulation of the A3G expression in hepatoma cell line （HuH-7） were investigated. Expression level of APOBEC3s mRNA in human liver was determined by RT-PCR. HuH-7 and HepG2 cells were treated with various concentrations of IFN-α（0 U/ml, 100 U/ml, 500 U/ml, 1000 U/ml）for 12 h. The mRNA levels were measured by a quantitative RT-PCR, the results were normalized relative to the specimens without IFN-α stimulation. Total protein of HuH-7 cells treated with various concentrations of IFN-α for 48 h was subjected to Western blot analysis. For reporter gene assay, HuH-7 cells were transfected with the reporter plasmids containing IRF- E sites and its mutants with different lengths. Then the cells were treated with or without 1200 U/ml IFN-α for additional 12 h （ 1000 U/ml） after 24 h of transfection, and the cell lysate was prepared and assayed for lueiferase activity. It was found that normal human liver expressed the rnR_NA of A3G. A3G mRNA expression in HuH-7 and HepG2 cells were up-regulated by IFN-α stimulation in a dose-depen- dent manner. Western blot analysis indicated that A3G protein expression was also enhanced by IFN-α stimulation. Sequence analysis showed the existence of putative sites of IFN regulatory factor element （IRF-E） in 5＇ region of A3G gene upstream the initiation eodon. IFN-α stimulation results in 6- to 8- fold increase in lueiferase activity in cells transfeeted with the plasmid containing IRF-E sites of the 5＇ upstream sequences, whereas luciferase activity did not change in cells transfected with the plasmid containing mutant IRF-E sites or without IRF-E sites. As a conclusion, A3G are expressed in normal human liver. A3G expression was up-regulated by IFN-α stimulation in hepatoma cells and could be involved in host defense mechanisms against HBV. IRF-E site in 5＇ region of APOBEC3G gene upstream the initiation codon plays an important role in this process.展开更多
目的探讨载脂蛋白B mRNA编辑酶催化多肽样蛋白3G(apolipoprotein B mRNA editing enzyme catalytic polypeptide like3G,APOBEC3G)(也称为CEM15)体外抗乙型肝炎病毒(HBV)的作用及其机制。方法脂质体转染pcDNA3.1 Human APOBEC3G-Myc-6X...目的探讨载脂蛋白B mRNA编辑酶催化多肽样蛋白3G(apolipoprotein B mRNA editing enzyme catalytic polypeptide like3G,APOBEC3G)(也称为CEM15)体外抗乙型肝炎病毒(HBV)的作用及其机制。方法脂质体转染pcDNA3.1 Human APOBEC3G-Myc-6Xhis、pcDAN3.1/His-C进入HepG2.2.15细胞,转染后,RT-PCR证实转染基因的表达,Western Blot证实蛋白的表达。通过ELISA方法检测细胞上清液中乙型肝炎表面抗原(HBsAg)及乙型肝炎e抗原(HBeAg),RT-PCR分析APOBEC3G对HBV mRNA转录的影响。结果APOBEC3G基因与蛋白在HepG2.2.15细胞都有表达,与空质粒转染组相比,pcDNA3.1 Human APOBEC3G-Myc-6Xhis转染组HBsAg含量下降70.38%,HBeAg含量下降62.88%,未转质粒细胞为空白对照组。结论APOBEC3G在体外可以抑制HBV复制,可以作为一种新型的抗病毒制剂治疗乙肝病毒感染。展开更多
基金Supported by the National Natural Science Foundation of China, No. 30271170 and 30571646 the National Key Basic Research Program of China, No. 20014CB510008
文摘AIM： To investigate the effect of APOBEC3G mediated antiviral activity against hepatitis B virus （HBV） in cell cultures and replication competent HBV vector-based mouse model. METHODS： The mammalian hepatoma cells Huh7 and HepG2 were cotransfected with various amounts of CMV-driven expression vector encoding APOBEC3G and replication competent 1.3 fold over-length HBV. Levels of HBsAg and HBeAg in the media of the transfected cells were determined by ELISA. The expression of HBcAg in transfected cells was detected by western blot. HBV DNA and RNA from intracellular core particles were examined by Northern and Southern blot analyses. To assess activity of the APOBEC3G in vivo, an HBV vector-based model was used in which APOBEC3G and the HBV vector were co-delivered via high-volume tail vein injection. Levels of HBsAg and HBV DNA in the sera of mice as well as HBV core-associated RNA in the liver of mice were determined by ELISA and quantitative PCR analysis respectively. RESULTS： There was a dose dependent decrease in the levels of intracellular core-associated HBV DNA and extracellular production of HBsAg and HBeAg. The levels of intracellular core-associated viral RNA also decreased, but the expression of HBcAg in transfected cells showed almost no change. Consistent with in vitro results, levels of HBsAg in the sera of mice were dramatically decreased. More than 1.5 log10 decrease in levels of serum HBV DNA and liver HBV RNA were observed in the APOBEC3G-treated groups compared with the control groups.CONCLUSION： These findings indicate that APOBEC3G could suppress HBV replication and antigen expression both in vivo and in vitro, promising an advance in treatment of HBV infection.
基金National Grand Fundamental Research 973 Program of China (2006CB504206).
文摘Interaction between the HIV-1 Vif protein and the cellular host APOBEC3G protein is a promising target for inhibition of HIV-1 replication. Considering that human cells are a very complicated environment for the study of protein interactions, the goal of this study was to check whether fission yeast could be used as a model cell for studying the Vif-APOBEC3G interaction. Vif and APOBEC3G were expressed in fusion with GFP protein in the S. pombe SP223 strain. Subcellular localizations of Vif and APOBEC3G were observed with fluorescent microscopy. Codon optimization was used to over express the Vif protein in S. pombe cells. The degradation of APOBEC3G mediated by Vif was tested through expressing Vif and GFP-APOBEC3G proteins in the same cell. Western Blot analysis was used to measure the corresponding protein levels under different experimental conditions. The results showed that the Vif protein was predominantly localized in the nucleus of S. pombe cells, APOBEC3G was localized in the cytoplasm and concentrated at punctate bodies that were often in close proximity to the nucleus but were not necessarily restricted from other regions in the cytoplasm. Vif protein expression levels were increased significantly by using codon optimization and APOBEC3G was degraded when Vif was over-expressed in the same S. pombe cells. These results indicate that fission yeast is a good model for studying the interaction between the Vif and APOBEC3G proteins.
文摘The highly active antiretroviral treatment (HAART) has allowed people living with HIV to live longer with a better quality of life. However, toxicity and the emergence of drug resistance arise from HAART use. Therefore, new antiretroviral therapy is needed since no cure or vaccine is available against HIV. Virus-host interaction has been proven to be important in the last decade. Host factors such as the C-C chemokine receptor type 5 (CCR5), a receptor used by HIV to penetrate host cells, have led to the discovery of the Maraviroc, which is an antiretroviral medication used in the United States. In contrast, other factors like C-X-C Motif Chemokine Receptor 4 (CXCR4) and the Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3G (APOBEC3G), a potent host defense factor against HIV, is under investigation. APOBEC3G antiviral activity remains a possible therapeutic target against HIV. This systematic review aimed to synthesize the available evidence on the role of APOBEC3G polymorphisms and their expression on HIV infection disease progression in Africa. We used Web of Science, PubMed, Embase, and Google Scholar and searched for relevant publications in French or English reporting on APOBEC3G polymorphisms association with HIV infection in African populations from January 2009 to May 2023. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyzes) was used to process for reporting systematic review. Fifteen studies were included, of which seven were on APOBEC3G polymorphisms and eight were on APOBEC3G expression. Among the APOBEC3G polymorphisms, the most studied was H186R or rs8177832. The average of the minor allele frequency of H186R of APOBEC3G available for the studies included in this study was 0.29 with a 95% CI (0.172;0.401) and varied from 0.108 reported in Uganda to 0.47 recorded from Burkina Faso. The polymorphism H186R was not associated with HIV status in Southern Africa. However, the referent allele of H186R was protective against HIV infection in Western Central Africa, while in West Africa, it was the minor allele (G) of H186R which was protective against HIV. This review warrants a need to increase research on APOBEC3G, from its variants to its hypermutations on the continent with an essential variety of HIV-1 subtypes, to impact the research on A3G-based anti-HIV strategies.
文摘载脂蛋白B m RNA编辑酶催化多肽3F(APOBEC3F)属固有免疫系统中的重要成员,对人免疫缺陷病毒(HIV)、乙型肝炎病毒(HBV)等多种病毒的复制具有广泛的抑制作用。为构建APOBEC3F基因的真核表达载体,并检测其在体外培养的MARC145细胞中的表达情况,通过RT-PCR从猪脾脏组织扩增APOBEC3F基因,定向克隆到表达增强型绿色荧光蛋白(EGFP)的真核表达载体p EGFP-CMV中,构建p EGFP-APOBEC3F。PCR扩增及测序显示,APOBEC3F插入载体位置、方向及序列均正确。p EGFP-APOBEC3F经脂质体介导法转染MARC145细胞,转染后24 h APOBEC3F m RNA的水平升至最高。细胞免疫化学法检测发现APOBEC3F蛋白主要在MARC145细胞质中表达。研究结果为体外研究猪APOBEC3F基因在抗猪蓝耳病中的作用奠定了基础。
文摘To clarify the role of APOBEC3G （A3G） in cellular defense against hepatitis B virus （HBV）, the expression of A3G in normal human liver and the regulation of the A3G expression in hepatoma cell line （HuH-7） were investigated. Expression level of APOBEC3s mRNA in human liver was determined by RT-PCR. HuH-7 and HepG2 cells were treated with various concentrations of IFN-α（0 U/ml, 100 U/ml, 500 U/ml, 1000 U/ml）for 12 h. The mRNA levels were measured by a quantitative RT-PCR, the results were normalized relative to the specimens without IFN-α stimulation. Total protein of HuH-7 cells treated with various concentrations of IFN-α for 48 h was subjected to Western blot analysis. For reporter gene assay, HuH-7 cells were transfected with the reporter plasmids containing IRF- E sites and its mutants with different lengths. Then the cells were treated with or without 1200 U/ml IFN-α for additional 12 h （ 1000 U/ml） after 24 h of transfection, and the cell lysate was prepared and assayed for lueiferase activity. It was found that normal human liver expressed the rnR_NA of A3G. A3G mRNA expression in HuH-7 and HepG2 cells were up-regulated by IFN-α stimulation in a dose-depen- dent manner. Western blot analysis indicated that A3G protein expression was also enhanced by IFN-α stimulation. Sequence analysis showed the existence of putative sites of IFN regulatory factor element （IRF-E） in 5＇ region of A3G gene upstream the initiation eodon. IFN-α stimulation results in 6- to 8- fold increase in lueiferase activity in cells transfeeted with the plasmid containing IRF-E sites of the 5＇ upstream sequences, whereas luciferase activity did not change in cells transfected with the plasmid containing mutant IRF-E sites or without IRF-E sites. As a conclusion, A3G are expressed in normal human liver. A3G expression was up-regulated by IFN-α stimulation in hepatoma cells and could be involved in host defense mechanisms against HBV. IRF-E site in 5＇ region of APOBEC3G gene upstream the initiation codon plays an important role in this process.
文摘目的探讨载脂蛋白B mRNA编辑酶催化多肽样蛋白3G(apolipoprotein B mRNA editing enzyme catalytic polypeptide like3G,APOBEC3G)(也称为CEM15)体外抗乙型肝炎病毒(HBV)的作用及其机制。方法脂质体转染pcDNA3.1 Human APOBEC3G-Myc-6Xhis、pcDAN3.1/His-C进入HepG2.2.15细胞,转染后,RT-PCR证实转染基因的表达,Western Blot证实蛋白的表达。通过ELISA方法检测细胞上清液中乙型肝炎表面抗原(HBsAg)及乙型肝炎e抗原(HBeAg),RT-PCR分析APOBEC3G对HBV mRNA转录的影响。结果APOBEC3G基因与蛋白在HepG2.2.15细胞都有表达,与空质粒转染组相比,pcDNA3.1 Human APOBEC3G-Myc-6Xhis转染组HBsAg含量下降70.38%,HBeAg含量下降62.88%,未转质粒细胞为空白对照组。结论APOBEC3G在体外可以抑制HBV复制,可以作为一种新型的抗病毒制剂治疗乙肝病毒感染。
