The effects of epigenetic modification on the differentiation of islet cells and the expression of associated genes（Pdx-1,Pax4,MafA,and Nkx6.1,etc） were investigated.The promoter methylation status of islet differen...The effects of epigenetic modification on the differentiation of islet cells and the expression of associated genes（Pdx-1,Pax4,MafA,and Nkx6.1,etc） were investigated.The promoter methylation status of islet differentiation-associated genes（Pdx-1,Pax4,MafA and Nkx6.1）,Oct4 and MLH1 genes of mouse embryonic stem cells,NIH3T3 cells and NIT-1 cells were profiled by methylated DNA immunoprecipitation,real-time quantitative PCR（MeDIP-qPCR） techniques.The histone modification status of these genes promoter region in different cell types was also measured by using chromatin immunoprecipitation real-time quantitative PCR methods.The expression of these genes in these cells was detected by using real-time quantitative PCR.The relationship between the epigenetic modification（DNA methylation,H3 acetylation,H3K4m3 and H3K9m3） of these genes and their expression was analyzed.The results showed that：（1） the transcription-initiation-sites of Pdx-1,MafA and Nkx6.1 were highly methylated in NIH3T3 cells; （2） NIH3T3 cells showed a significantly higher level of DNA methylation modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and NIT-1 cells（P〈0.05）; （3） NIT-1 cells had a significantly higher level of H3K4m3 modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and NIH3T3 cells（P〈0.05）,with significantly increased level of gene expression; （4） NIH3T3 cell had a significantly higher level of H3K9m3 modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and with NIT-1 cell（P〈0.05）,with no detectable mRNA expression of these genes.It was concluded that histone modification（H3K4m3 and H3K9m3） and DNA methylation might have an intimate communication between each other in the differentiation process from embryonic stem cells into islet cells.展开更多
目的建立检测人血清中抗白色念珠菌H3K4甲基转移酶N末端肽段（N—terminal region of histone 3 lysine 4 methyhransferase，Setl-208p）IgG类抗体的ELISA方法，评估其在侵袭性念珠菌病（invasive candidiasis，IC）患者中的早期诊断...目的建立检测人血清中抗白色念珠菌H3K4甲基转移酶N末端肽段（N—terminal region of histone 3 lysine 4 methyhransferase，Setl-208p）IgG类抗体的ELISA方法，评估其在侵袭性念珠菌病（invasive candidiasis，IC）患者中的早期诊断价值。方法收集IC患者（105例）、定植患者（37例）、细菌感染患者（25例）、其他真菌感染患者（10例）以及健康体检者（200例）血清，用Setl-208p作为包被抗原，血清1：500稀释，以羊抗人IgG-HRP为二抗，测定人血清中相应的抗Setl-208p抗体水平，确定cut-off值并考查方法的敏感度、特异度和准确度。结果以重组Setl-208p抗原建立的ELISA法精密度良好，批内变异系数（coefficient of variation，CV）为5．5％，批间CV为10．4％。重组抗原对血清中相应抗体的阻断率为91．8％，根据ROC曲线，选择吸光度（absorbance，A）值0．40作为cut off值，对IC的诊断敏感度为79．2％，特异度为90％，且与细菌感染及其他真菌感染病人（如曲霉）无非特异交叉反应。此外，IC患者中抗Setl-208p抗体阳性率（76．1％，80／105）显著高于念珠菌定植者抗Setl-208p抗体阳性率（32．4％，12／37）（χ^2=22．9，P〈0．01）。结论建立了检测抗白念珠菌抗Setl-208p抗体的ELISA法，在IC早期诊断中具有潜在应用价值。展开更多
The MLL/SET family of histone H3 lysine 4 methyltransferases form enzyme complexes with core subunits ASH2L, WDR5, RbBP5, and DPY-30 （often abbreviated WRAD）, and are responsible for global histone H3 iysine 4 methy...The MLL/SET family of histone H3 lysine 4 methyltransferases form enzyme complexes with core subunits ASH2L, WDR5, RbBP5, and DPY-30 （often abbreviated WRAD）, and are responsible for global histone H3 iysine 4 methylation, a hallmark of actively transcribed chromatin in mammalian cells. Accordingly, the function of these proteins is required for a wide variety of processes including stem cell differentiation, cell growth and division, body segmentation, and hematopoiesis. While most work on MLL-WRAD has focused on the function this core complex in histone methylation, recent studies indicate that MLL-WRAD proteins interact with a variety of other proteins and IncRNAs and can localize to cellular organelles beyond the nucleus. In this review, we focus on the recently described activities and interacting partners of MLL-WRAD both inside and outside the nucleus.展开更多
目的通过比较不同细胞类型之间胰腺十二指肠同源盒1（Pdx-1）、配对盒基因4（Pax4）、MafA（mast cell function associated antigen）和Nkx6．1等胰岛组织特异性基因其转录起始区的H3K4m3和H3K9m3修饰的差异，探讨H3K4nd和H3K9m3修饰...目的通过比较不同细胞类型之间胰腺十二指肠同源盒1（Pdx-1）、配对盒基因4（Pax4）、MafA（mast cell function associated antigen）和Nkx6．1等胰岛组织特异性基因其转录起始区的H3K4m3和H3K9m3修饰的差异，探讨H3K4nd和H3K9m3修饰对胰岛组织特异性基因表达的作用。方法采用染色质免疫共沉淀．实时定量聚合酶链反应（PCR）法检测小鼠胚胎干细胞（mES，1×10^7）、小鼠成纤维细胞株NIH3T3细胞（1×10^7）和小鼠B细胞株NIT-1细胞（1×10^7）三者中的胰岛组织特异性基因、Oct4基因和MLH1基因转录起始区H3K4rrd和H3K9m3修饰的状况。同时采用实时定量逆转录（RT）-PCR检测上述3种细胞各基因mRNA表达水平。分析H3K4m3和H3K9m3修饰改变与基因表达之间的关系。结果NIT-1细胞中Pdx-1、Pax4、MafA、Nkx6．1等胰岛组织特异性基因转录起始区的H3K4m的修饰水平分别为：（4．84±0．05）％、（9．91±1．33）％、（10．64±0．87）％、（0．23±0．03）％，与mES细胞比较明显增高（P〈0．05），基因表达；NIH3T3细胞中Pdx-1、Pax4、MafA、Nkx6．1等胰岛组织特异性基因转录起始区的H3Kgm3的修饰水平分别为：（0．64±0．21）％、（7．04±1．29）％、（0．39±0．10）％、（2．35±0．81）％，与mES细胞比较明显增高（P〈0．05），基因不表达。结论mK4n13与H3K9m3修饰能相互协调，共同调控胰岛组织特异性基因的表达。展开更多
文摘The effects of epigenetic modification on the differentiation of islet cells and the expression of associated genes（Pdx-1,Pax4,MafA,and Nkx6.1,etc） were investigated.The promoter methylation status of islet differentiation-associated genes（Pdx-1,Pax4,MafA and Nkx6.1）,Oct4 and MLH1 genes of mouse embryonic stem cells,NIH3T3 cells and NIT-1 cells were profiled by methylated DNA immunoprecipitation,real-time quantitative PCR（MeDIP-qPCR） techniques.The histone modification status of these genes promoter region in different cell types was also measured by using chromatin immunoprecipitation real-time quantitative PCR methods.The expression of these genes in these cells was detected by using real-time quantitative PCR.The relationship between the epigenetic modification（DNA methylation,H3 acetylation,H3K4m3 and H3K9m3） of these genes and their expression was analyzed.The results showed that：（1） the transcription-initiation-sites of Pdx-1,MafA and Nkx6.1 were highly methylated in NIH3T3 cells; （2） NIH3T3 cells showed a significantly higher level of DNA methylation modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and NIT-1 cells（P〈0.05）; （3） NIT-1 cells had a significantly higher level of H3K4m3 modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and NIH3T3 cells（P〈0.05）,with significantly increased level of gene expression; （4） NIH3T3 cell had a significantly higher level of H3K9m3 modification in the transcription-initiation-site of Pdx-1,Pax4,MafA and Nkx6.1 genes than that in mES cells and with NIT-1 cell（P〈0.05）,with no detectable mRNA expression of these genes.It was concluded that histone modification（H3K4m3 and H3K9m3） and DNA methylation might have an intimate communication between each other in the differentiation process from embryonic stem cells into islet cells.
文摘目的建立检测人血清中抗白色念珠菌H3K4甲基转移酶N末端肽段（N—terminal region of histone 3 lysine 4 methyhransferase，Setl-208p）IgG类抗体的ELISA方法，评估其在侵袭性念珠菌病（invasive candidiasis，IC）患者中的早期诊断价值。方法收集IC患者（105例）、定植患者（37例）、细菌感染患者（25例）、其他真菌感染患者（10例）以及健康体检者（200例）血清，用Setl-208p作为包被抗原，血清1：500稀释，以羊抗人IgG-HRP为二抗，测定人血清中相应的抗Setl-208p抗体水平，确定cut-off值并考查方法的敏感度、特异度和准确度。结果以重组Setl-208p抗原建立的ELISA法精密度良好，批内变异系数（coefficient of variation，CV）为5．5％，批间CV为10．4％。重组抗原对血清中相应抗体的阻断率为91．8％，根据ROC曲线，选择吸光度（absorbance，A）值0．40作为cut off值，对IC的诊断敏感度为79．2％，特异度为90％，且与细菌感染及其他真菌感染病人（如曲霉）无非特异交叉反应。此外，IC患者中抗Setl-208p抗体阳性率（76．1％，80／105）显著高于念珠菌定植者抗Setl-208p抗体阳性率（32．4％，12／37）（χ^2=22．9，P〈0．01）。结论建立了检测抗白念珠菌抗Setl-208p抗体的ELISA法，在IC早期诊断中具有潜在应用价值。
文摘The MLL/SET family of histone H3 lysine 4 methyltransferases form enzyme complexes with core subunits ASH2L, WDR5, RbBP5, and DPY-30 （often abbreviated WRAD）, and are responsible for global histone H3 iysine 4 methylation, a hallmark of actively transcribed chromatin in mammalian cells. Accordingly, the function of these proteins is required for a wide variety of processes including stem cell differentiation, cell growth and division, body segmentation, and hematopoiesis. While most work on MLL-WRAD has focused on the function this core complex in histone methylation, recent studies indicate that MLL-WRAD proteins interact with a variety of other proteins and IncRNAs and can localize to cellular organelles beyond the nucleus. In this review, we focus on the recently described activities and interacting partners of MLL-WRAD both inside and outside the nucleus.
文摘目的通过比较不同细胞类型之间胰腺十二指肠同源盒1（Pdx-1）、配对盒基因4（Pax4）、MafA（mast cell function associated antigen）和Nkx6．1等胰岛组织特异性基因其转录起始区的H3K4m3和H3K9m3修饰的差异，探讨H3K4nd和H3K9m3修饰对胰岛组织特异性基因表达的作用。方法采用染色质免疫共沉淀．实时定量聚合酶链反应（PCR）法检测小鼠胚胎干细胞（mES，1×10^7）、小鼠成纤维细胞株NIH3T3细胞（1×10^7）和小鼠B细胞株NIT-1细胞（1×10^7）三者中的胰岛组织特异性基因、Oct4基因和MLH1基因转录起始区H3K4rrd和H3K9m3修饰的状况。同时采用实时定量逆转录（RT）-PCR检测上述3种细胞各基因mRNA表达水平。分析H3K4m3和H3K9m3修饰改变与基因表达之间的关系。结果NIT-1细胞中Pdx-1、Pax4、MafA、Nkx6．1等胰岛组织特异性基因转录起始区的H3K4m的修饰水平分别为：（4．84±0．05）％、（9．91±1．33）％、（10．64±0．87）％、（0．23±0．03）％，与mES细胞比较明显增高（P〈0．05），基因表达；NIH3T3细胞中Pdx-1、Pax4、MafA、Nkx6．1等胰岛组织特异性基因转录起始区的H3Kgm3的修饰水平分别为：（0．64±0．21）％、（7．04±1．29）％、（0．39±0．10）％、（2．35±0．81）％，与mES细胞比较明显增高（P〈0．05），基因不表达。结论mK4n13与H3K9m3修饰能相互协调，共同调控胰岛组织特异性基因的表达。
