目的:克隆丝裂原活化蛋白激酶激酶6(mitogen-activated protein kinase kinase 6,MKK6)基因启动子,研究泛素水解酶22(ubiquitin specific peptidase 22,USP22)对MKK6转录活性的调控作用。方法:采用PCR扩增MKK6基因启动子片段,并以该片...目的:克隆丝裂原活化蛋白激酶激酶6(mitogen-activated protein kinase kinase 6,MKK6)基因启动子,研究泛素水解酶22(ubiquitin specific peptidase 22,USP22)对MKK6转录活性的调控作用。方法:采用PCR扩增MKK6基因启动子片段,并以该片段为模板对USP22结合位点进行定点突变,将野生型与突变型启动子片段定向插入荧光素酶表达载体pGL3-Basic;用重组载体与内参质粒pRL-TK共转染HeLa细胞,行双荧光素酶活性检测以确定其转录活性;利用染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)实验观察USP22蛋白与MKK6启动子是否存在直接的结合;下调USP22表达后,检测MKK6转录活性的变化。结果:成功扩增MKK6启动子及其突变体并构建荧光素酶表达载体;USP22结合位点的突变导致该启动子活性在HeLa细胞中明显降低(P<0.05);USP22与MKK6启动子在细胞中存在直接结合;抑制USP22的表达导致MKK6转录水平明显下降(P<0.05)。结论:在HeLa细胞中,USP22有效地调控MKK6基因的转录。展开更多
The genome wide dynamic profiling of chromatin accessibility in early osteogenic differentiation of human mesenchymal stem cells(MSCs)has not been reported.In this study,the sixth generation primary cultured human MSC...The genome wide dynamic profiling of chromatin accessibility in early osteogenic differentiation of human mesenchymal stem cells(MSCs)has not been reported.In this study,the sixth generation primary cultured human MSCs were treated with osteogenic inducer for 0 day,3 days,5 days and 7 days,respectively,and then harvested for assay for transposase accessible chromatin using sequencing(ATAC seq).The numbers of chromatin accessibility,the specific activated DNA motifs in chromatin accessibility regions and the functional enrichment analysis of peak adjacent genes were analyzed by bioinformatics.展开更多
With sulfonated electrospun polystyrene fiber as a template, uniform polyaniline（PANI） nanotubes were fabricated via polymerization of aniline followed by template removal. Au nanoparticles（Aunano） were decorated ...With sulfonated electrospun polystyrene fiber as a template, uniform polyaniline（PANI） nanotubes were fabricated via polymerization of aniline followed by template removal. Au nanoparticles（Aunano） were decorated on the PANI nanotube successfully via auto-reduction of HAuCl4 on the PANI nanotube. The morphology of the nanotubes was characterized by means of scanning electron microscopy（SEM） and transmittance electron microscopy（TEM）. By varying precursor concentration and incubation time, Aunano-PANI with different size of Aunano was obtained conveniently. Glassy carbon electrode modified with the Aunano decorated PANI nanotubes （Auna,o-PANI/GCE） was prepared and used seccessfully for the catalytic oxidation of ascorbic acid（AA）. The results of differential pulse voltammetry indicate that there is a good linear relationship between the peak currents and the concentrations of AA in the range of 5-3000 μmol/L, with the limit of detection of 1 μmol/L（S/N〉3）. There is no mutual interference between AA and dopamine. The electrode has been successfully applied in the detection of AA in vitamin C tablet sample.展开更多
文摘目的:克隆丝裂原活化蛋白激酶激酶6(mitogen-activated protein kinase kinase 6,MKK6)基因启动子,研究泛素水解酶22(ubiquitin specific peptidase 22,USP22)对MKK6转录活性的调控作用。方法:采用PCR扩增MKK6基因启动子片段,并以该片段为模板对USP22结合位点进行定点突变,将野生型与突变型启动子片段定向插入荧光素酶表达载体pGL3-Basic;用重组载体与内参质粒pRL-TK共转染HeLa细胞,行双荧光素酶活性检测以确定其转录活性;利用染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)实验观察USP22蛋白与MKK6启动子是否存在直接的结合;下调USP22表达后,检测MKK6转录活性的变化。结果:成功扩增MKK6启动子及其突变体并构建荧光素酶表达载体;USP22结合位点的突变导致该启动子活性在HeLa细胞中明显降低(P<0.05);USP22与MKK6启动子在细胞中存在直接结合;抑制USP22的表达导致MKK6转录水平明显下降(P<0.05)。结论:在HeLa细胞中,USP22有效地调控MKK6基因的转录。
文摘The genome wide dynamic profiling of chromatin accessibility in early osteogenic differentiation of human mesenchymal stem cells(MSCs)has not been reported.In this study,the sixth generation primary cultured human MSCs were treated with osteogenic inducer for 0 day,3 days,5 days and 7 days,respectively,and then harvested for assay for transposase accessible chromatin using sequencing(ATAC seq).The numbers of chromatin accessibility,the specific activated DNA motifs in chromatin accessibility regions and the functional enrichment analysis of peak adjacent genes were analyzed by bioinformatics.
基金Supported by the National Natural Science Foundation of China（Nos.21105009, 21476047） and the Project of the State Key Laboratory of Electroanalytical Chemistry, China（No.SKLEAC201205）.
文摘With sulfonated electrospun polystyrene fiber as a template, uniform polyaniline（PANI） nanotubes were fabricated via polymerization of aniline followed by template removal. Au nanoparticles（Aunano） were decorated on the PANI nanotube successfully via auto-reduction of HAuCl4 on the PANI nanotube. The morphology of the nanotubes was characterized by means of scanning electron microscopy（SEM） and transmittance electron microscopy（TEM）. By varying precursor concentration and incubation time, Aunano-PANI with different size of Aunano was obtained conveniently. Glassy carbon electrode modified with the Aunano decorated PANI nanotubes （Auna,o-PANI/GCE） was prepared and used seccessfully for the catalytic oxidation of ascorbic acid（AA）. The results of differential pulse voltammetry indicate that there is a good linear relationship between the peak currents and the concentrations of AA in the range of 5-3000 μmol/L, with the limit of detection of 1 μmol/L（S/N〉3）. There is no mutual interference between AA and dopamine. The electrode has been successfully applied in the detection of AA in vitamin C tablet sample.
