植物多向耐药性(Pleiotropic drug resistance,PDR)蛋白属于三磷酸腺苷结合盒(ATP-binding cassette,ABC)转运蛋白ABCG亚族,在植物次生代谢产物转运特别是萜类物质跨膜转运中发挥重要作用。基于辽东楤木全基因组测序鉴定出21个PDR转运蛋...植物多向耐药性(Pleiotropic drug resistance,PDR)蛋白属于三磷酸腺苷结合盒(ATP-binding cassette,ABC)转运蛋白ABCG亚族,在植物次生代谢产物转运特别是萜类物质跨膜转运中发挥重要作用。基于辽东楤木全基因组测序鉴定出21个PDR转运蛋白,且主要为细胞膜蛋白,该基因在12对染色体上均有分布,其中5号染色体上分布较多。共线性分析结果表明,部分PDR基因在进化过程中发生基因串联复制事件,并可能存在基因多拷贝扩增现象。基因结构分析结果表明,17个基因含有PDR基因特有结构域,且启动子上含有多种激素和非生物胁迫响应相关顺式作用元件。组织特异性表达模式分析结果表明,PDR基因主要在辽东楤木叶片中高表达。为筛选与辽东楤木三萜皂苷转运相关的PDR转运蛋白,对基因编码区序列、蛋白结构、跨膜螺旋等进行分析,初步筛选出7个结构完整的PDR转运蛋白。进一步通过系统进化分析、基因表达与皂苷含量的关联分析筛选出2个可能与楤木皂苷转运相关的PDR基因(AE02G00218和AE12G01725)。两个基因均受外源激素MeJA、SA和机械损伤诱导上调表达。以上研究为萜类物质转运相关蛋白鉴定与功能研究提供新思路和基因资源。展开更多
An increasing number of tunnels are being constructed with tunnel-boring machines （TBMs） due to the increased efficiency and shorter completion time resulting from their use. However, when a TBM encoun- ters adverse...An increasing number of tunnels are being constructed with tunnel-boring machines （TBMs） due to the increased efficiency and shorter completion time resulting from their use. However, when a TBM encoun- ters adverse geological conditions in the course of tunnel construction （e.g., karst caves, faults, or frac- tured zones）, disasters such as water and mud inrush, collapse, or machine blockage may result, and may severely imperil construction safety. Therefore, the advance detection of adverse geology and water-bearing conditions in front of the tunnel face is of great importance. This paper uses the TBM tun- neling of the water conveyance project from Songhua River as a case study in order to propose a compre- hensive forward geological prospecting technical system that is suitable for TBM tunnel construction under complicated geological conditions. By combining geological analysis with forward geological prospecting using a three-dimensional （3D） induced polarization method and a 3D seismic method, a comprehensive forward geological prospecting technical system can accurately forecast water inrush geo-hazards or faults in front of the TBM tunnel face. In this way, disasters such as water and mud inrush, collapse, or machine blockage can be avoided. This prospecting technical system also has reference value for carrying out the forward prospecting of adverse geology for potential TBM tunneling and for ensuring that a TBM can work efficiently.展开更多
文摘植物多向耐药性(Pleiotropic drug resistance,PDR)蛋白属于三磷酸腺苷结合盒(ATP-binding cassette,ABC)转运蛋白ABCG亚族,在植物次生代谢产物转运特别是萜类物质跨膜转运中发挥重要作用。基于辽东楤木全基因组测序鉴定出21个PDR转运蛋白,且主要为细胞膜蛋白,该基因在12对染色体上均有分布,其中5号染色体上分布较多。共线性分析结果表明,部分PDR基因在进化过程中发生基因串联复制事件,并可能存在基因多拷贝扩增现象。基因结构分析结果表明,17个基因含有PDR基因特有结构域,且启动子上含有多种激素和非生物胁迫响应相关顺式作用元件。组织特异性表达模式分析结果表明,PDR基因主要在辽东楤木叶片中高表达。为筛选与辽东楤木三萜皂苷转运相关的PDR转运蛋白,对基因编码区序列、蛋白结构、跨膜螺旋等进行分析,初步筛选出7个结构完整的PDR转运蛋白。进一步通过系统进化分析、基因表达与皂苷含量的关联分析筛选出2个可能与楤木皂苷转运相关的PDR基因(AE02G00218和AE12G01725)。两个基因均受外源激素MeJA、SA和机械损伤诱导上调表达。以上研究为萜类物质转运相关蛋白鉴定与功能研究提供新思路和基因资源。
文摘An increasing number of tunnels are being constructed with tunnel-boring machines （TBMs） due to the increased efficiency and shorter completion time resulting from their use. However, when a TBM encoun- ters adverse geological conditions in the course of tunnel construction （e.g., karst caves, faults, or frac- tured zones）, disasters such as water and mud inrush, collapse, or machine blockage may result, and may severely imperil construction safety. Therefore, the advance detection of adverse geology and water-bearing conditions in front of the tunnel face is of great importance. This paper uses the TBM tun- neling of the water conveyance project from Songhua River as a case study in order to propose a compre- hensive forward geological prospecting technical system that is suitable for TBM tunnel construction under complicated geological conditions. By combining geological analysis with forward geological prospecting using a three-dimensional （3D） induced polarization method and a 3D seismic method, a comprehensive forward geological prospecting technical system can accurately forecast water inrush geo-hazards or faults in front of the TBM tunnel face. In this way, disasters such as water and mud inrush, collapse, or machine blockage can be avoided. This prospecting technical system also has reference value for carrying out the forward prospecting of adverse geology for potential TBM tunneling and for ensuring that a TBM can work efficiently.
