AIM:To investigate the reciprocal modulation between microRNA(miRNA) and DNA methylation via exploring the correlation between miR-373 and methyl-CpGbinding domain protein(MBD)2.METHODS:MiR-373 expression was examined...AIM:To investigate the reciprocal modulation between microRNA(miRNA) and DNA methylation via exploring the correlation between miR-373 and methyl-CpGbinding domain protein(MBD)2.METHODS:MiR-373 expression was examined using the TaqMan miRNA assay.Methylation of miR-373 was investigated using methylation-specific polymerase chain reaction,and recruitment of methyl binding proteins was studied using the chromatin immunoprecipitation assay.Mutation analysis was conducted using the QuikChange Site-Directed Mutagenesis kit.The activity of miR-373 gene promoter constructs and targeting at MBD2-three prime untranslated region(3'UTR) by miR-373 were evaluated by a dual-luciferase reporter gene assay.RESULTS:In hilar cholangiocarcinoma,miR-373 decreased and was closely associated with poor cell differentiation,advanced clinical stage,and shorter survival.The promoter-associated CpG island of miR-373 gene was hypermethylated and inhibited expression of miR-373.MBD2 was up-regulated and enriched at the promoter-associated CpG island of miR-373.Methylation-mediated suppression of miR-373 required MBD2 enrichment at the promoter-associated CpG island,and miR-373 negatively regulated MBD2 expression through targeting the 3'UTR.CONCLUSION:MiR-373 behaves as a direct transcriptional target and negative regulator of MBD2 activity through a feedback loop of CpG island methylation.展开更多
Summary： The role of methyl-CpG binding domain protein 2 （MBD2） in an ApoE-deficient mouse model of age-related macular degeneration （AMD） was investigated. Eight-week-old Mbd2/ApoE double deficient （Mbd2^-/- Ap...Summary： The role of methyl-CpG binding domain protein 2 （MBD2） in an ApoE-deficient mouse model of age-related macular degeneration （AMD） was investigated. Eight-week-old Mbd2/ApoE double deficient （Mbd2^-/- ApoE^-/-） mice （n=12, 24 eyes, experimental group） and MBD2 （wt） ApoE^-/- mice （n=12, 24 eyes, control group） were fed on Western-type diet for 4 months. The mice were sacrificed, and total serum cholesterol levels were analyzed and Bruch＇s membrane （BM） of the eyes was removed for ultrastructural observation by transmission electron microscopy. Moreover, intercellular adhesion molecule 1 （ICAM-1） immunoreactivities were evaluated by fluorescence microscopy in sections of the eyes in both groups for further understanding the function mechanism of MBD2. There was no significant difference in the total serum cholesterol levels between control group and experimental group （P〉0.05）. Transmission electron microscopy revealed that AMD-like lesions, various vacuoles accumulated on BM, notable outer collagenous layer deposits and dilated basal infoldings of retinal pigment epithelium （RPE） were seen in both groups, and the BM in control group was significantly thickened as compared with experimental group （P〈0.05）. Fluorescence micrographs exhibited the expression of ICAM-1 in choroid was higher in control group than in experimental group. We are led to conclude that MBD2 gene knockout may lead to accumulation of more deposits on the BM and influence the pathogenesis of AMD via triggering endothelial activation and inflammatory response in choroid, improving microcirculation, and reducing lipid deposition so as to inhibit the development of AMD-like lesions. Our study helps to provide a new therapeutic approach for the clinical treatment of AMD.展开更多
X-linked methyl-CpG binding protein 2 mutations can induce symptoms similar to those of Parkinson’s disease and dopamine metabolism disorders, but the specific role of X-linked methyl-CpG binding protein 2 in the pat...X-linked methyl-CpG binding protein 2 mutations can induce symptoms similar to those of Parkinson’s disease and dopamine metabolism disorders, but the specific role of X-linked methyl-CpG binding protein 2 in the pathogenesis of Parkinson’s disease remains unknown. In the present study, we used 6-hydroxydopamine-induced human neuroblastoma cell （SH-SY5Y cells） injury as a cell model of Parkinson’s disease. The 6-hydroxydopamine （50 μmol/L） treatment decreased protein levels for both X-linked methyl-CpG binding protein 2 and tyrosine hydroxylase in these cells, and led to cell death. However, overexpression of X-linked methyl-CpG binding protein 2 was able to ameliorate the effects of 6-hydroxydopamine, it reduced 6-hydroxydopamine-induced apoptosis, and increased the levels of tyrosine hydroxylase in SH-SY5Y cells. These findings suggesting that X-linked methyl-CpG binding protein 2 may be a potential therapeutic target for the treatment of Parkinson’s disease.展开更多
背景甲基化CpG结合蛋白2(methyl-CpG-binding protein 2,MeCP2)在基因转录调控中发挥重要作用,研究表明MeCP2可能是胶质瘤治疗的一个新靶点,但其在胶质瘤中的表达与患者预后的关系尚不清楚。目的探讨MeCP2在胶质瘤中的表达与患者手术后...背景甲基化CpG结合蛋白2(methyl-CpG-binding protein 2,MeCP2)在基因转录调控中发挥重要作用,研究表明MeCP2可能是胶质瘤治疗的一个新靶点,但其在胶质瘤中的表达与患者预后的关系尚不清楚。目的探讨MeCP2在胶质瘤中的表达与患者手术后临床预后的关系。方法选择2016年1月—2018年10月在贵阳市第二人民医院神经外科手术治疗的临床病理资料完整的96例胶质瘤患者,应用免疫组织化学方法检测肿瘤组织和正常脑组织中MeCP2的表达,随访患者生存情况。采用Kaplan-Meier法进行生存分析;采用Cox单因素和多因素风险回归模型分析MeCP2表达水平及相关临床病理因素与患者生存预后的关系。结果96例患者获得随访,其中男51例,女45例,年龄7~79岁,平均年龄(44.9±18.3)岁。免疫组化结果显示胶质瘤组织中MeCP2阳性表达率高于正常脑组织(75.0%vs 30.0%,P<0.05)。MeCP2表达的阳性率在WHOⅠ~Ⅳ级胶质瘤组织中分别为20.0%、66.7%、75.0%、90.6%(1/5、18/27、24/32、29/32),在高级别胶质瘤(WHOⅢ、Ⅳ级)中的阳性表达率高于低级别胶质瘤(WHOⅠ、Ⅱ级),差异有统计学意义(P<0.05)。70例出现肿瘤复发,59例死亡,中位无进展生存期(progression-free survival,PFS)和总生存期(overall survival,OS)分别为(10.7±1.7)个月和(24.1±2.9)个月。Kaplan-Meier生存分析显示,胶质瘤患者中MeCP2高表达组的中位PFS和OS显著低于低表达组[PFS:(15.6±1.8)个月vs(28.0±2.6)个月,P=0.026;OS:(16.1±2.0)个月vs(28.3±5.8)个月,P=0.022]。Cox回归分析显示,MeCP2高表达(HR:1.705,95%CI:1.019~2.854)、肿瘤病变多发(HR:2.727,95%CI:1.453~5.120)、单纯采用手术治疗(HR:1.704,95%CI:1.015~2.861)、高病理级别(WHOⅢ、Ⅳ级)(HR:3.294,95%CI:2.317~4.683)是胶质瘤患者预后不良的独立危险因素。结论MeCP2在胶质瘤手术患者中表达水平上调,且高表达水平与胶质瘤患者术后不良预后相关。展开更多
Classical methyl-CpG binding proteins contain the conserved DNA binding motif methyl-cytosine binding domain(MBD), which preferentially binds to methylated CpG dinucleotides. These proteins serve as transcriptional re...Classical methyl-CpG binding proteins contain the conserved DNA binding motif methyl-cytosine binding domain(MBD), which preferentially binds to methylated CpG dinucleotides. These proteins serve as transcriptional repressors,mediating gene silencing via DNA cytosine methylation. Mutations in methyl-CpG binding protein 2 (MeCP2) have beenlinked to the human mental retardation disorder Rett syndrome, suggesting an important role for methyl-CpG bindingproteins in brain development and function. This mini-review summarizes the recent advances in studying the diversefunctions of MeCP2 as a prototype for other methyl-CpG binding proteins in the development and function of thevertebrate nervous system.展开更多
目的探讨甲基CpG结合蛋白2(methyl-CpG-binding protein 2,MeCP2)基因单核苷酸多态性与中国长江以南汉族人群系统性红斑狼疮(systemic lupus erythematosus,SLE)的易感性。方法采用病例对照研究设计,收集病例141例,对照144例。应用聚合...目的探讨甲基CpG结合蛋白2(methyl-CpG-binding protein 2,MeCP2)基因单核苷酸多态性与中国长江以南汉族人群系统性红斑狼疮(systemic lupus erythematosus,SLE)的易感性。方法采用病例对照研究设计,收集病例141例,对照144例。应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)技术对rs2239464、rs2075596两位点进行基因分型,在不同的遗传模式下分析两个位点基因多态性与SLE的相关性。根据赤池信息准则(Akaike’s information criteria,AIC)值最小原则,筛选最优模型。结果在显性、隐性、相加及相乘遗传模式下,两位点基因型或等位基因频率分布在病例组与对照组间的差异均有统计学意义(P<0.05)。显性遗传模式下,rs2239464、rs2075596位点GG/AG基因型为SLE的保护性基因型(ORrs2239464=0.528,95%CIrs2239464:0.315～0.885;ORrs2075596=0.435,95%CIrs2075596:0.264～0.717)。隐性遗传模式下,rs2239464、rs2075596位点GG基因型在统计学上具有显著的保护性作用(ORrs2239464=0.108,95%CIrs2239464:0.013～0.863;ORrs2075596=0.097,95%CIrs2075596:0.012～0.771)。相加遗传模式下,以AA基因型为参照,rs2239464位点GG基因型为SLE的保护性基因型(OR=0.094,95%CI:0.012～0.758),rs2075596位点AG及GG基因型也具有保护性作用(ORAG=0.498,95%CIAG:0.298～0.832;ORGG=0.077,95%CIGG:0.010～0.612)。相乘遗传模式下,rs2239464、rs2075596两位点的G等位基因为SLE的保护性等位基因(ORrs2239464=0.503,95%CIrs2239464:0.319～0.793;ORrs2075596=0.445,95%CIrs2075596:0.289～0.686)。rs2239464,rs2075596位点的最优遗传模式均为相加遗传模式。结论在中国长江以南汉族人群中MECP2基因rs2239464,rs2075596位点基因多态性与SLE相关,突变等位基因G可能是SLE保护性等位基因。展开更多
目的:应用甲基CpG结合蛋白-2(methyl-CpG-binding protein 2,MECP2)基因突变筛查方法,检测孤独症患者的MECP2基因,探讨孤独症与MECP2基因的关系。方法:收集男性孤独症44例,均满足孤独症《美国精神障碍诊断和统计手册》第4版诊断标准,应...目的:应用甲基CpG结合蛋白-2(methyl-CpG-binding protein 2,MECP2)基因突变筛查方法,检测孤独症患者的MECP2基因,探讨孤独症与MECP2基因的关系。方法:收集男性孤独症44例,均满足孤独症《美国精神障碍诊断和统计手册》第4版诊断标准,应用变性高效液相色谱(denaturing high performance liquid chromatography,DHPLC)筛查MECP2基因变异,并进行DNA测序鉴定。对存在MECP2基因错义突变的病例进行家系调查。结果:在44例患者中经DHPLC筛查阳性和DNA测序发现,4例患者存在不同的MECP2基因突变,包括c.590C>T(T197M)和c.602C>T(A201V)2种错义突变,以及c.1053C>G、c.897C>T 2种同义突变;17例的内含子3位于Exon 4前74位点C>T,为SNP(rs2071569);1例c.602C>T错义突变患者家系调查发现,突变来源于母亲及外祖父,母亲呈杂合子,为X染色体随机失活,母亲与外祖父智力均正常,外祖父有抑郁症。结论:在男性孤独症患者中,存在MECP2基因较高的变异率,MECP2基因在孤独症致病中可能起着一定作用,不除外是孤独症的易感基因。展开更多
基金Supported by National Natural Science Foundation of China,No. 81071998Hubei Natural Science Foundation,No.2008CDB159Specialized Research Fund for the Doctoral Program of Higher Education,No. 20070487114
文摘AIM:To investigate the reciprocal modulation between microRNA(miRNA) and DNA methylation via exploring the correlation between miR-373 and methyl-CpGbinding domain protein(MBD)2.METHODS:MiR-373 expression was examined using the TaqMan miRNA assay.Methylation of miR-373 was investigated using methylation-specific polymerase chain reaction,and recruitment of methyl binding proteins was studied using the chromatin immunoprecipitation assay.Mutation analysis was conducted using the QuikChange Site-Directed Mutagenesis kit.The activity of miR-373 gene promoter constructs and targeting at MBD2-three prime untranslated region(3'UTR) by miR-373 were evaluated by a dual-luciferase reporter gene assay.RESULTS:In hilar cholangiocarcinoma,miR-373 decreased and was closely associated with poor cell differentiation,advanced clinical stage,and shorter survival.The promoter-associated CpG island of miR-373 gene was hypermethylated and inhibited expression of miR-373.MBD2 was up-regulated and enriched at the promoter-associated CpG island of miR-373.Methylation-mediated suppression of miR-373 required MBD2 enrichment at the promoter-associated CpG island,and miR-373 negatively regulated MBD2 expression through targeting the 3'UTR.CONCLUSION:MiR-373 behaves as a direct transcriptional target and negative regulator of MBD2 activity through a feedback loop of CpG island methylation.
基金supported by grants from Natural Science Foundation of Hubei Province(No:2012FFB02304)Scientific Research Foundation of Ministry of Education(No:2013-1792),China
文摘Summary： The role of methyl-CpG binding domain protein 2 （MBD2） in an ApoE-deficient mouse model of age-related macular degeneration （AMD） was investigated. Eight-week-old Mbd2/ApoE double deficient （Mbd2^-/- ApoE^-/-） mice （n=12, 24 eyes, experimental group） and MBD2 （wt） ApoE^-/- mice （n=12, 24 eyes, control group） were fed on Western-type diet for 4 months. The mice were sacrificed, and total serum cholesterol levels were analyzed and Bruch＇s membrane （BM） of the eyes was removed for ultrastructural observation by transmission electron microscopy. Moreover, intercellular adhesion molecule 1 （ICAM-1） immunoreactivities were evaluated by fluorescence microscopy in sections of the eyes in both groups for further understanding the function mechanism of MBD2. There was no significant difference in the total serum cholesterol levels between control group and experimental group （P〉0.05）. Transmission electron microscopy revealed that AMD-like lesions, various vacuoles accumulated on BM, notable outer collagenous layer deposits and dilated basal infoldings of retinal pigment epithelium （RPE） were seen in both groups, and the BM in control group was significantly thickened as compared with experimental group （P〈0.05）. Fluorescence micrographs exhibited the expression of ICAM-1 in choroid was higher in control group than in experimental group. We are led to conclude that MBD2 gene knockout may lead to accumulation of more deposits on the BM and influence the pathogenesis of AMD via triggering endothelial activation and inflammatory response in choroid, improving microcirculation, and reducing lipid deposition so as to inhibit the development of AMD-like lesions. Our study helps to provide a new therapeutic approach for the clinical treatment of AMD.
基金sponsored by the Ph.D.Independent Research Projects of Wuhan University,No.201130302020017a grant from the Science and Technology Bureau of Hubei Province,No.2011CDB511the National Natural Science Foundation of China,No.81170769
文摘X-linked methyl-CpG binding protein 2 mutations can induce symptoms similar to those of Parkinson’s disease and dopamine metabolism disorders, but the specific role of X-linked methyl-CpG binding protein 2 in the pathogenesis of Parkinson’s disease remains unknown. In the present study, we used 6-hydroxydopamine-induced human neuroblastoma cell （SH-SY5Y cells） injury as a cell model of Parkinson’s disease. The 6-hydroxydopamine （50 μmol/L） treatment decreased protein levels for both X-linked methyl-CpG binding protein 2 and tyrosine hydroxylase in these cells, and led to cell death. However, overexpression of X-linked methyl-CpG binding protein 2 was able to ameliorate the effects of 6-hydroxydopamine, it reduced 6-hydroxydopamine-induced apoptosis, and increased the levels of tyrosine hydroxylase in SH-SY5Y cells. These findings suggesting that X-linked methyl-CpG binding protein 2 may be a potential therapeutic target for the treatment of Parkinson’s disease.
文摘Classical methyl-CpG binding proteins contain the conserved DNA binding motif methyl-cytosine binding domain(MBD), which preferentially binds to methylated CpG dinucleotides. These proteins serve as transcriptional repressors,mediating gene silencing via DNA cytosine methylation. Mutations in methyl-CpG binding protein 2 (MeCP2) have beenlinked to the human mental retardation disorder Rett syndrome, suggesting an important role for methyl-CpG bindingproteins in brain development and function. This mini-review summarizes the recent advances in studying the diversefunctions of MeCP2 as a prototype for other methyl-CpG binding proteins in the development and function of thevertebrate nervous system.
文摘目的探讨甲基CpG结合蛋白2(methyl-CpG-binding protein 2,MeCP2)基因单核苷酸多态性与中国长江以南汉族人群系统性红斑狼疮(systemic lupus erythematosus,SLE)的易感性。方法采用病例对照研究设计,收集病例141例,对照144例。应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)技术对rs2239464、rs2075596两位点进行基因分型,在不同的遗传模式下分析两个位点基因多态性与SLE的相关性。根据赤池信息准则(Akaike’s information criteria,AIC)值最小原则,筛选最优模型。结果在显性、隐性、相加及相乘遗传模式下,两位点基因型或等位基因频率分布在病例组与对照组间的差异均有统计学意义(P<0.05)。显性遗传模式下,rs2239464、rs2075596位点GG/AG基因型为SLE的保护性基因型(ORrs2239464=0.528,95%CIrs2239464:0.315～0.885;ORrs2075596=0.435,95%CIrs2075596:0.264～0.717)。隐性遗传模式下,rs2239464、rs2075596位点GG基因型在统计学上具有显著的保护性作用(ORrs2239464=0.108,95%CIrs2239464:0.013～0.863;ORrs2075596=0.097,95%CIrs2075596:0.012～0.771)。相加遗传模式下,以AA基因型为参照,rs2239464位点GG基因型为SLE的保护性基因型(OR=0.094,95%CI:0.012～0.758),rs2075596位点AG及GG基因型也具有保护性作用(ORAG=0.498,95%CIAG:0.298～0.832;ORGG=0.077,95%CIGG:0.010～0.612)。相乘遗传模式下,rs2239464、rs2075596两位点的G等位基因为SLE的保护性等位基因(ORrs2239464=0.503,95%CIrs2239464:0.319～0.793;ORrs2075596=0.445,95%CIrs2075596:0.289～0.686)。rs2239464,rs2075596位点的最优遗传模式均为相加遗传模式。结论在中国长江以南汉族人群中MECP2基因rs2239464,rs2075596位点基因多态性与SLE相关,突变等位基因G可能是SLE保护性等位基因。
文摘目的:应用甲基CpG结合蛋白-2(methyl-CpG-binding protein 2,MECP2)基因突变筛查方法,检测孤独症患者的MECP2基因,探讨孤独症与MECP2基因的关系。方法:收集男性孤独症44例,均满足孤独症《美国精神障碍诊断和统计手册》第4版诊断标准,应用变性高效液相色谱(denaturing high performance liquid chromatography,DHPLC)筛查MECP2基因变异,并进行DNA测序鉴定。对存在MECP2基因错义突变的病例进行家系调查。结果:在44例患者中经DHPLC筛查阳性和DNA测序发现,4例患者存在不同的MECP2基因突变,包括c.590C>T(T197M)和c.602C>T(A201V)2种错义突变,以及c.1053C>G、c.897C>T 2种同义突变;17例的内含子3位于Exon 4前74位点C>T,为SNP(rs2071569);1例c.602C>T错义突变患者家系调查发现,突变来源于母亲及外祖父,母亲呈杂合子,为X染色体随机失活,母亲与外祖父智力均正常,外祖父有抑郁症。结论:在男性孤独症患者中,存在MECP2基因较高的变异率,MECP2基因在孤独症致病中可能起着一定作用,不除外是孤独症的易感基因。
