Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested ...Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested for suitability of Agrobacterium tumefaciens-mediated transformation by using immature embryos as explants.Infection ability and efficiency of transformation of A.tumefaciens sp.strains EHA105 and LBA4404,different heat treatment times of immature embryos before infection,influence of L-cysteine addition in co-cultivation medium after transformation,and how different ways of selection and cultivation influence the efficiency of transformation were compared.Glyphosate-resistant gene 2mG2-EPSPS was transformed into several typical maize genotypes including 78599,Zong 31 and BA,under the optimum conditions.Results showed that the hypervirulent Agrobacterium tumefaciens sp.strain EHA105 was more infectious than LBA4404.Inclusion of L-cysteine（100 mg L-1） in co-cultivation medium,and heating of the immature embryos for 3 min prior to infection led to a significant increase in the transformation efficiency.Growth in resting medium for 4-10 d and delaying selection was beneficial to the survival of resistant calli.During induction of germination,adding a high concentration of 6-BA（5 mg L-1） and a low concentration of 2,4-D（0.2 mg L-1） to regeneration medium significantly enhanced germination percentage.Using the optimized transformation procedure,more than 800 transgenic plants were obtained from 78599,Zong 31 and BA.By spraying herbicide glyphosate on leaves of transgenic lines,we identified 66 primary glyphosate-resistant plants.The transformation efficiency was 8.2%.PCR and Southern-blot analyses confirmed the integration of the transgenes in the maize genome.展开更多
植物固醇血症(OMIM:210250)是罕见的遗传代谢病,于1974年首次被报道,其主要临床特征为血清植物固醇水平增加,总胆固醇水平轻到中度增高[1-2]、多发皮肤肌腱黄色瘤及早发动脉粥样硬化等心血管疾病,严重者于5岁左右死于心肌梗死[3]。由于...植物固醇血症(OMIM:210250)是罕见的遗传代谢病,于1974年首次被报道,其主要临床特征为血清植物固醇水平增加,总胆固醇水平轻到中度增高[1-2]、多发皮肤肌腱黄色瘤及早发动脉粥样硬化等心血管疾病,严重者于5岁左右死于心肌梗死[3]。由于临床表型酷似纯合型家族性高胆固醇血症,也称为假性纯合型家族性高胆固醇血症,极易误诊漏诊误治[4]。目前认为植物固醇血症发病率为1/600万,全球报道病例仅约百例[5]。植物固醇血症的主要致病基因不同于家族性高胆固醇血症,为三磷酸腺苷结合盒转运体G5或G8(ATP binding cassette subfamily G member 5或8分别由ABCG5、ABCG8基因编码)缺陷[1]。展开更多
基金supported by the National Key Project of transgenic varieties breeding(2009ZX08003-003B)the Light of West Talent Training Project of China(2010-2011)the Project of Sichuan Province Finance Genetic Engineering,China(2011JYGC01-002)
文摘Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested for suitability of Agrobacterium tumefaciens-mediated transformation by using immature embryos as explants.Infection ability and efficiency of transformation of A.tumefaciens sp.strains EHA105 and LBA4404,different heat treatment times of immature embryos before infection,influence of L-cysteine addition in co-cultivation medium after transformation,and how different ways of selection and cultivation influence the efficiency of transformation were compared.Glyphosate-resistant gene 2mG2-EPSPS was transformed into several typical maize genotypes including 78599,Zong 31 and BA,under the optimum conditions.Results showed that the hypervirulent Agrobacterium tumefaciens sp.strain EHA105 was more infectious than LBA4404.Inclusion of L-cysteine（100 mg L-1） in co-cultivation medium,and heating of the immature embryos for 3 min prior to infection led to a significant increase in the transformation efficiency.Growth in resting medium for 4-10 d and delaying selection was beneficial to the survival of resistant calli.During induction of germination,adding a high concentration of 6-BA（5 mg L-1） and a low concentration of 2,4-D（0.2 mg L-1） to regeneration medium significantly enhanced germination percentage.Using the optimized transformation procedure,more than 800 transgenic plants were obtained from 78599,Zong 31 and BA.By spraying herbicide glyphosate on leaves of transgenic lines,we identified 66 primary glyphosate-resistant plants.The transformation efficiency was 8.2%.PCR and Southern-blot analyses confirmed the integration of the transgenes in the maize genome.
文摘植物固醇血症(OMIM:210250)是罕见的遗传代谢病,于1974年首次被报道,其主要临床特征为血清植物固醇水平增加,总胆固醇水平轻到中度增高[1-2]、多发皮肤肌腱黄色瘤及早发动脉粥样硬化等心血管疾病,严重者于5岁左右死于心肌梗死[3]。由于临床表型酷似纯合型家族性高胆固醇血症,也称为假性纯合型家族性高胆固醇血症,极易误诊漏诊误治[4]。目前认为植物固醇血症发病率为1/600万,全球报道病例仅约百例[5]。植物固醇血症的主要致病基因不同于家族性高胆固醇血症,为三磷酸腺苷结合盒转运体G5或G8(ATP binding cassette subfamily G member 5或8分别由ABCG5、ABCG8基因编码)缺陷[1]。
