DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study...DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study, methylation-sensitive amplified polymorphisms （MSAP） were used to investigate DNA methylation profiles of cassava polyploidy following cold treatment to identify candidate genes involved in response to cold stress. The result showed that the genome-wide DNA methylation polymorphisms accounted for 34.02%-42.56% in SC8 and its autotetraploid exposed to 5 ~C for 2, 8, 24 and 48 h, respectively. The methylation levels of SC8 at 2 h-cold stress were the highest during 48h under cold treatments. With the time extension within 48 h under cold stress, the methylation levels gradually decreased to the same level as the control but DNA methylation levels of cassava autotetraploid were stable within 48 h. For future analysis of the methylation extent, the cold stress induced more DNA methylation than demethylation in SC8, where DNA methylation was consistent with demethylation in its autotetraploid. The expression analysis demonstrated increase in the transcription of one methylated gene and decrease in the transcription of two demethylated genes. The results revealed that gene methylations in specific sites would be a rapidly epigenetic response to cold stress, further elucidating the methylation functions in its autotetraploid.展开更多
外膜蛋白A(OmpA)在细菌的致病中表现出多种功能,包括对宿主细胞的粘附、侵袭等,是介导病原菌与宿主相互作用的关健因子。本研究以维氏单胞菌C4基因组DNA为模板,扩增330 bp和442 bp OmpA的上下游同源臂片段,成功构建自杀重组质粒pRE112-...外膜蛋白A(OmpA)在细菌的致病中表现出多种功能,包括对宿主细胞的粘附、侵袭等,是介导病原菌与宿主相互作用的关健因子。本研究以维氏单胞菌C4基因组DNA为模板,扩增330 bp和442 bp OmpA的上下游同源臂片段,成功构建自杀重组质粒pRE112-ΔOmpA;将重组质粒转化至E.coli WM3064,再双亲接合至维氏气单胞菌中,基于同源重组的原理在8%蔗糖板上成功筛选得到维氏气单胞菌C4 OmpA基因敲除菌ΔOmpA。生长特性测定结果表明敲除株ΔOmpA较野生菌株WT生长更为缓慢,本研究结果为进一步研究OmpA基因在维氏单胞菌中的功能提供了科学依据。展开更多
文摘DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study, methylation-sensitive amplified polymorphisms （MSAP） were used to investigate DNA methylation profiles of cassava polyploidy following cold treatment to identify candidate genes involved in response to cold stress. The result showed that the genome-wide DNA methylation polymorphisms accounted for 34.02%-42.56% in SC8 and its autotetraploid exposed to 5 ~C for 2, 8, 24 and 48 h, respectively. The methylation levels of SC8 at 2 h-cold stress were the highest during 48h under cold treatments. With the time extension within 48 h under cold stress, the methylation levels gradually decreased to the same level as the control but DNA methylation levels of cassava autotetraploid were stable within 48 h. For future analysis of the methylation extent, the cold stress induced more DNA methylation than demethylation in SC8, where DNA methylation was consistent with demethylation in its autotetraploid. The expression analysis demonstrated increase in the transcription of one methylated gene and decrease in the transcription of two demethylated genes. The results revealed that gene methylations in specific sites would be a rapidly epigenetic response to cold stress, further elucidating the methylation functions in its autotetraploid.
