植物器官的大小调控是一个重要的生物学过程,直接影响农作物产量。目前对于植物器官大小调控的研究集中在转录调控、激素信号通路及蛋白质合成与修饰等多个水平和途径,但具体的分子机制并不是很清晰。李云海实验室前期研究发现了一个器...植物器官的大小调控是一个重要的生物学过程,直接影响农作物产量。目前对于植物器官大小调控的研究集中在转录调控、激素信号通路及蛋白质合成与修饰等多个水平和途径,但具体的分子机制并不是很清晰。李云海实验室前期研究发现了一个器官大小的关键调控基因UBIQUITIN SPECIFIC PROTEASE 15(UBP15)/SUPPRESSOR2 OF DA1(SOD2)。sod2-1突变体由于UBP15基因缺失导致器官变小。UBP15作为DA1的底物,其蛋白稳定性受DA1的调节,但其下游通路并不清楚。为了进一步了解UBP15调控器官大小的分子机制,通过EMS诱变筛选分离得到了sod2-1的抑制突变体sus40-1D。sus40-1D sod2-1突变体与sod2-1植株相比,子叶、花瓣和种子面积显著增大。遗传分析表明sus40-1D为显性突变。基因组重测序及连锁分析鉴定出2个与sus40-1D紧密连锁的候选基因:At1g05820和At1g08470。At1g05820的突变发生在内含子区域,而At1g08470的突变发生在外显子区。本研究发现了一个调控器官大小的突变体sus40-1D,对该突变体的进一步研究将有助于解析植物器官大小的调控机制。展开更多
Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of water...Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of waters, aquatic biota, and crops. As human exposure to chlordecone is mainly due to food contamination, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contamination of yam, sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam, courgette, and tomato under greenhouse conditions with homogenized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contaminated in accordance with the chlordecone content of the soils; ii) the plant contamination capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contamination was related to the soil volumetric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontamination by means of plant extraction. Soil contact accounted for most of the root crop contamination, which was inversely proportional to the tuber size. Internal transfer might also increase root crop contamination when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contamination without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contamination and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionmaking tool for farmers, relating soil pollution with the maximal contamination of the harvested organs to predict crop contamination and thus assisting farmers in making crop choices at planting in order to conform with the European Union's regulations.展开更多
基金supported by Research Fund of the Doctoral Program of Higher Education(200805720004)Scientific Research Foundation for Returned Scholars,Ministry of Education of China([2009]1001)
文摘植物器官的大小调控是一个重要的生物学过程,直接影响农作物产量。目前对于植物器官大小调控的研究集中在转录调控、激素信号通路及蛋白质合成与修饰等多个水平和途径,但具体的分子机制并不是很清晰。李云海实验室前期研究发现了一个器官大小的关键调控基因UBIQUITIN SPECIFIC PROTEASE 15(UBP15)/SUPPRESSOR2 OF DA1(SOD2)。sod2-1突变体由于UBP15基因缺失导致器官变小。UBP15作为DA1的底物,其蛋白稳定性受DA1的调节,但其下游通路并不清楚。为了进一步了解UBP15调控器官大小的分子机制,通过EMS诱变筛选分离得到了sod2-1的抑制突变体sus40-1D。sus40-1D sod2-1突变体与sod2-1植株相比,子叶、花瓣和种子面积显著增大。遗传分析表明sus40-1D为显性突变。基因组重测序及连锁分析鉴定出2个与sus40-1D紧密连锁的候选基因:At1g05820和At1g08470。At1g05820的突变发生在内含子区域,而At1g08470的突变发生在外显子区。本研究发现了一个调控器官大小的突变体sus40-1D,对该突变体的进一步研究将有助于解析植物器官大小的调控机制。
基金Supported by the Ministry of Ecology and Sustainable Development and the Ministry of Agriculture and Food,France,the French National Agency of Research,and the French National Chlordecone Action Plan
文摘Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of waters, aquatic biota, and crops. As human exposure to chlordecone is mainly due to food contamination, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contamination of yam, sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam, courgette, and tomato under greenhouse conditions with homogenized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contaminated in accordance with the chlordecone content of the soils; ii) the plant contamination capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contamination was related to the soil volumetric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontamination by means of plant extraction. Soil contact accounted for most of the root crop contamination, which was inversely proportional to the tuber size. Internal transfer might also increase root crop contamination when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contamination without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contamination and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionmaking tool for farmers, relating soil pollution with the maximal contamination of the harvested organs to predict crop contamination and thus assisting farmers in making crop choices at planting in order to conform with the European Union's regulations.
