With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate th...With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere.展开更多
The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new str...The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new strategy for development of glyphosate-tolerant crops,the plant expression vector pG2-GAT harboring gat and G2-aroA(encoding EPSPS)has been transformed into tobacco(Nicotiana tabacum)to develop novel plants with higher tolerance to glyphosate.Results from Southern and Western blotting analyses indicated that the target genes were integrated into tobacco chromosomes and expressed effectively at the protein level.Glyphosate tolerance was compared among transgenic tobacco plants containing gat,G2-aroA,or both genes.Plants containing both gat and G2-aroA genes were the most glyphosate-tolerant.This study has shown that a combination of different strategies may result in higher tolerance in transgenic crops,providing a new approach for development of glyphosate-tolerant crops.展开更多
CRISPR-Cas9 is a common tool for gene editing, and appropriate sg RNAs are the key factor for successful editing. In this study, the effect of sg RNA length and number on editing efficiency was analyzed in rice using ...CRISPR-Cas9 is a common tool for gene editing, and appropriate sg RNAs are the key factor for successful editing. In this study, the effect of sg RNA length and number on editing efficiency was analyzed in rice using CYP81 A6 as the target gene. A series of CRISPR-Cas9 plant expression vectors containing single sg RNAs with different lengths(17, 18, 19, 20, 21, 22, 23 nt) or two sg RNAs were constructed and introduced into rice cultivar Zhonghua11 by Agrobacterium-mediated transformation. Analysis of the editing status of 1283 transgenic rice plants showed that 371 were successfully edited with base preference.Single A or T insertions were the most frequent among the six edited types. The editing efficiency of transgenic rice with two sg RNAs was higher than that with a single sg RNA. Editing efficiency and sg RNA length showed a normal distribution with 20 nt sg RNA(25%) being the most efficient. The editing efficiency decreased slightly with decreases of 1–2 bases(19 nt 20%, 18 nt 21%), but decreased significantly with a decrease of 3 bases(17 nt 4.5%). Editing efficiency was significantly reduced by adding 1 to 3 bases(21 nt 16.8%, 22 nt 13%, 23 nt 13%) to the sg RNA. These results provide data for successful gene editing or rice by CRISPR-Cas9.展开更多
Transgenic safety issues cause more and more controversies with the planting area of transgenie crops increased year by year. Gene flow from transgenie crops to wild relatives through pollen dispersal is one of the fo...Transgenic safety issues cause more and more controversies with the planting area of transgenie crops increased year by year. Gene flow from transgenie crops to wild relatives through pollen dispersal is one of the focus problems. Gene splitting technique provides a new strategy for the control of transgene flow by bio-logical containment. The construction of gene splitting technique is based on protein trans-splicing mediated by intein. Currently, it has been proved in Arabidopsis, tabaoco, wheat, etc. that active and functional proteins can be reassembled by intein mediated protein trans-splicing after gene splitting, which provides theoretical basis and experimental supporting for the limit of transgene flow by gene splitting technique. The theoretical basis of gene splitting technique and research progresses of its application on the control of transgene flow were reviewed in this paper.展开更多
基金supported by the Major Project of China on New Varieties of GMO Cultivation (2012ZX08011-003 and 2014ZX08011-004B)
文摘With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere.
基金supported by the National Basic Research Program of China(2007CB707805)the National High Technology Research and Development Program of China(2006AA020101)the National Natural Science Foundation of China(30470047and 30200007)
文摘The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new strategy for development of glyphosate-tolerant crops,the plant expression vector pG2-GAT harboring gat and G2-aroA(encoding EPSPS)has been transformed into tobacco(Nicotiana tabacum)to develop novel plants with higher tolerance to glyphosate.Results from Southern and Western blotting analyses indicated that the target genes were integrated into tobacco chromosomes and expressed effectively at the protein level.Glyphosate tolerance was compared among transgenic tobacco plants containing gat,G2-aroA,or both genes.Plants containing both gat and G2-aroA genes were the most glyphosate-tolerant.This study has shown that a combination of different strategies may result in higher tolerance in transgenic crops,providing a new approach for development of glyphosate-tolerant crops.
基金supported by the Central Public-interest Scientific Institution Basal Research Fund。
文摘CRISPR-Cas9 is a common tool for gene editing, and appropriate sg RNAs are the key factor for successful editing. In this study, the effect of sg RNA length and number on editing efficiency was analyzed in rice using CYP81 A6 as the target gene. A series of CRISPR-Cas9 plant expression vectors containing single sg RNAs with different lengths(17, 18, 19, 20, 21, 22, 23 nt) or two sg RNAs were constructed and introduced into rice cultivar Zhonghua11 by Agrobacterium-mediated transformation. Analysis of the editing status of 1283 transgenic rice plants showed that 371 were successfully edited with base preference.Single A or T insertions were the most frequent among the six edited types. The editing efficiency of transgenic rice with two sg RNAs was higher than that with a single sg RNA. Editing efficiency and sg RNA length showed a normal distribution with 20 nt sg RNA(25%) being the most efficient. The editing efficiency decreased slightly with decreases of 1–2 bases(19 nt 20%, 18 nt 21%), but decreased significantly with a decrease of 3 bases(17 nt 4.5%). Editing efficiency was significantly reduced by adding 1 to 3 bases(21 nt 16.8%, 22 nt 13%, 23 nt 13%) to the sg RNA. These results provide data for successful gene editing or rice by CRISPR-Cas9.
基金Supported by Major Project of China on New Varieties of GMO Cultivation(2013zx08010-003)National Natural Science Foundation of China(31100408)
文摘Transgenic safety issues cause more and more controversies with the planting area of transgenie crops increased year by year. Gene flow from transgenie crops to wild relatives through pollen dispersal is one of the focus problems. Gene splitting technique provides a new strategy for the control of transgene flow by bio-logical containment. The construction of gene splitting technique is based on protein trans-splicing mediated by intein. Currently, it has been proved in Arabidopsis, tabaoco, wheat, etc. that active and functional proteins can be reassembled by intein mediated protein trans-splicing after gene splitting, which provides theoretical basis and experimental supporting for the limit of transgene flow by gene splitting technique. The theoretical basis of gene splitting technique and research progresses of its application on the control of transgene flow were reviewed in this paper.
