抗除草剂草甘膦EPSPs基因在小麦中的转化

通过基因枪法,用抗除草剂草甘膦的ＥＰＳＰｓ基因转化小麦京花１号的幼穗约１０００个,及幼胚约８００个,经草甘膦选择后分别获得３８株和４株再生植株。这些再生植株经ＰＣＲ和（或）Ｓｏｕｔｈｅｒｎ杂交证明,其中有部分再生植株的基因组中稳定整合了外源ＥＰＳＰｓ基因,并且转化体中部分是可育的。首次用实验证明,抗除草剂草甘膦的ＥＰＳＰｓ基因作为单子叶禾谷类作物小麦基因转化的选择标记是行之有效的。     

小麦中外源基因瞬间表达调控研究及兔防御素（NP—1）基因的转化

将不同５上游调控序列驱动下的ＧＵＳ基因用基因枪法导入小麦幼胚和胚性愈伤组织,通过组织化学分析法和荧光分析法对ＧＵＳ基因的表达进行定量检测,比较了几种烟草花叶病毒（ＴＭＶ）Ω增强子序列对小麦中外源基因瞬间表达的调控作用;然后将其中效率最高的玉米Ｕｂｉｌ启动子与兔防御素（ＮＰ－１）连接起来,并加上Ｎｏｓ终止子,构民ＮＰ－１基因小麦表达载体,并转化小麦幼胚,经ＰＣＲ－Ｓｕｔｈｅｒｎ ｂｌｏｔ分析,初步确     

用基因枪法将人工雄性不育基因导入小麦的研究初报

利用ＰＤＳ１０００／氦气基因枪将人工构建的雄性不育基因（ＴＡ２９－Ｂａｒｎａｓｅ基因）导入小麦栽培品种豫责１８号的幼胚细胞。然后在含有１０～２０ｍｇ／Ｌ除草剂Ｂａｓｔａ的培养基础上筛选与分化。从１７０个幼胚中获得６株绿苗,对照的７０个幼胚中未得到绿苗。对其中３株已生根且长势好的绿苗进行Ｓｏｕｔｈｅｍ杂交分析,结果表明,这３株绿苗皆为转基因植株,转化效率达１．８％。     

根癌农杆菌介导的小麦转基因植株再生

根癌农杆菌菌株Ａｇｌ Ⅰ的Ｔｉ质粒ｐ＾ＵＮＮ－２带有Ｕｂｉ１启动子驱动的ｎｐｔⅡ基因。７种基因型小麦幼胚或胚性愈伤组织用于农杆菌介导的转化实验。经过不同家度巴龙霉素的筛选,３种基因型小麦产生抗性愈伤组织并再生植株。再生植株经ＰＣＲ和Ｓｏｕｔｈｅｒｎ杂交鉴定为转基因植株,转化频率为３．７％－５．９％。小麦基因型及转化材料的起始生理状态的影响Ｔ－ＤＮＡ转移的重要因素。     

利用激光微束穿刺法将外源基因导入小麦的研究

用激光微束穿刺法将携带有新霉素磷酸转移酶（ＮＰＴ－Ⅱ）基因的质粒ｐＪＩＴ１０１导入京花１号小麦幼胚细胞。方法是将小麦幼胚细胞进行高渗缓冲液预处理,用微米级的激光微束处理,然后在卡那霉素培养基上筛选出具抗性的愈伤组织及绿色小植株。第一年,从１５０个小麦幼胚中,在卡那霉素培养基上筛选出４株绿苗,取两株进行ＮＰＴ－Ⅱ酶活性分析,测到了ＮＰＴ－Ⅱ酶的活性。第二年重复实验,从２４５个小麦幼胚中,经筛选获得１株绿苗,进行了叶片ＤＮＡＰＣＲ扩增检测,转化的绿色小苗扩增出所导入的ＮＰＴ－Ⅱ基因编码的片段。结果表明,外源ＮＰＴ－Ⅱ基因已导入了小麦,并实现了整合表达。     

玉米幼胚高效再生系统的建立

建立了玉米幼胚高效再生系统。经研究发现,苏玉1号、农大3138、农大108的幼胚培养在含有2,4－D（2.5mg/L）的IM培养基上后,大多数幼胚能愈伤化并增大,形成基部相连、上部分开的微芽结构;微芽结构在转移到BM培养基上后,形成小植株;进一步转移到RM培养基上,它们长根并形成完整杆株。玉米幼胚高效再生植株与下列因素有关：玉米基因型、幼胚大小、幼胚长芽至分化时间、6－BA、IBA、Gelrite。不同品种玉米再生能力有显著差异,幼胚大小在1－2mm之间再生能力强,幼胚长芽至分化时间4－6d最好。激素6－BA浓度在0.5-0.6mg/L之间有利于微芽形成小植株,IBA浓度在0.6-1.0mg/L促进生根。Gelirte可代替琼脂粉用于玉米生根。     

CHI-PAT双价基因遗传转化贵州禾来拢

以贵州禾来拢幼胚为转化受体,用农杆菌介导法将几丁质酶和抗除草剂抗性双价基因(CHI-PAT)导入来拢幼胚,筛选出抗性愈伤组织并获得抗性植株.抗性植株经GUS组织化学及PCR检测呈阳性,转基因植株对50 mg/L的Basta溶液有抗性.初步证明CHI和PAT基因已整合进了水稻基因组中.     

通过基因枪轰击转化获得转基因小麦植株的研究

利用ＪＱ－７００型高速基因枪将ｐＤＭ３０２质粒ＤＮＡ上的ｂａｒ基因即ＰＡＴ酶基因导入了冬小麦品种“农大１４６”的幼胚中。经过在含有的选择培养基上筛选,得到了９块具有ｐｐｔ抗性的愈伤组织。ＰＣＲ电泳检测与ＰＣＲ－Ｓｏｕｔｈｅｒｎ发要交结果显示,外源ｂａｒ基因已转化进了由其中４块愈伤组织再生出的转基因的小麦植株中。     

Transgeni根癌农杆菌介导的小麦转基因植株再生(英文)

根癌农杆菌菌株Ａｇｌ Ⅰ的Ｔｉ 质粒ｐＵＮＮ－２ 带有Ｕｂｉ１ 启动子驱动的ｎｐｔ Ⅱ基因。７ 种基因型小麦幼胚或胚性愈伤组织用于农杆菌介导的转化实验。经过不同浓度巴龙霉素的筛选,３ 种基因型小麦产生抗性愈伤组织并再生植株。再生植株经ＰＣＲ 和Ｓｏｕｔｈｅｒｎ 杂交鉴定为转基因植株,转化频率（ 再生转基因植株的小麦愈伤组织数／ 用于转化实验的愈伤组织数） 为３．７％ ～５ ．９％ 。小麦基因型及转化材料的起始生理状态是影响ＴＤＮＡ转移的重要因素。     

水稻幼胚电激转化及转基因植株再生

幼胚的遗传转化对研究植物胚胎发育相关基因的表达与调控具有重要意义 ,也为植物遗传改良提供新的技术。本研究借助一种自制的特殊装置 ,采用电激法将GFP基因转入 2 - 3天水稻幼胚 ,得到瞬时表达 ,4- 6天水稻幼胚经电激后再生了植株 ,并在愈伤组织阶段及R0植株中检测到GFP荧光的转基因植株 ,从而建立了水稻幼胚的遗传转化实验系统。在电容为 5 0 0 μF、电压为 30 0V/cm ,浓度为 10 0 μg/mL的条件下 ,幼胚GFP的电激转化频率可达 35 %。在pH 5 .8的电激缓冲液中 ,最高转化频率可达 40 %。在三种不同的启动子实验中 ,以Ubi启动子的转化频率最高。     

Genetic transformation of the commercial barley (Hordeum vulgare L.) cultivar Conlon by particle bombardment of callus

Commercial barley cultivars are difficult to transform because of the lack of an efficient regeneration system. By modifying certain components in the standard culture medium, we have developed a reproducible and more efficient regeneration system. Herbicide-resistant transgenic plants from barley (Hordeum vulgare L. cv. Conlon) were obtained using this medium. Embryo-derived callus was bombarded with pAHC25, which contains the screenable marker gus (#-glucuronidase) and the selectable marker bar (bialaphos resistance gene), both driven by the maize ubiquitin promoter (Ubi1) and followed by the nos terminator. Following bombardment, callus was transferred to callus-induction medium supplemented with 5 mg/l bialaphos for selection. Resistant calli were subsequently transferred to maintenance medium containing 5 mg/l bialaphos for further selection and finally transferred to regeneration medium with 5 mg/l bialaphos. Green shoots that developed on the regeneration medium were transferred to rooting medium containing 3 mg/l bialaphos. Eighty-five transgenic plants were obtained from 13 independent transformation events. Progeny tests showed Mendelian inheritance for the transgenes. This is the first report of the production of large numbers of transgenic plants from a commercial cultivar adapted to Midwestern US barley production.     

Rapid Production of Multiple Independent Lines of Fertile Transgenic Wheat (Triticum aestivum)

Improvement of wheat (Triticum aestivum) by biotechnological approaches is currently limited by a lack of efficient and reliable transformation methodology. In this report, we detail a protocol for transformation of a highly embryogenic wheat cultivar, Bobwhite. Calli derived from immature embryos, 0.5 to 1 mm long, were bombarded with microprojectiles coated with DNA containing as marker genes the bar gene, encoding phosphinothricin-resistance, and the gene encoding [beta]-glucuronidase (GUS), each under control of a maize ubiquitin promoter. The bombardment was performed 5 d after embryo excision, just after initiation of callus proliferation. The ability of plantlets to root in the presence of 1 or 3 mg/L of bialaphos was the most reliable selection criteria used to identify transformed plants. Stable transformation was confirmed by marker gene expression assays and the presence of the bar sequences in high molecular weight chromosomal DNA of the resultant plants. Nine independent lines of fertile transgenic wheat plants have been obtained thus far, at a frequency of 1 to 2 per 1000 embryos bombarded. On average, 168 d elapsed between embryo excision for bombardment and anthesis of the T0 plants. The transmission of both the resistance phenotype and bar DNA to the T1 generation verified that germline transformation had occurred.     

温度和水分对不同基因型小麦未成熟胚体细胞胚胎发生以及分化能力的影响

对小麦未成熟胚盾片组织离体再生途径中,未成熟胚发育时期以及不同小麦品种的体细胞胚发生能力和体细胞胚的分化能力进行了研究,在所 试的14个小麦品种中,筛选出具有很强的体细胞胚发生能力和体细胞胚分化能力的4个品种,西农1376、盐2号、85＋1－3和宝丰7228。为进一步给小麦离体遗传操作打下基础,研究还对温度的影响进行了分析。通过低温手段解决了胚性愈伤组织随继代天数的延长体细胞胚分化能力快速降低的问题,同时研究还首次分析了干燥处理对小麦体细胞胚转换能力的影响,建立起一套高效的小麦离体培养再生体系,而且该体系从接种未成熟胚到再生植株移至土壤只需10－12周时间,避免了长期培养过程中存在的体细胞变异问题。     

Production of fertile transgenic wheat plants by laser micropuncture.

A modified, non-damaging, protocol for the production of fertile transgenic wheat (Triticum aestivum L. cultivar Giza 164) plants by laser micropuncture was developed. The new homemade setup secures the transformation of as many as 60 immature embryo-derived calli (10000 cells each) in less than one hour using a UV excimer laser with two dimensional translation stages, a suitable computer program and a proper optical system. Five-day-old calli were irradiated by a focused laser microbeam to puncture momentarily made self-healing holes ( approximately 0.5 microm) in the cell wall and membrane to allow uptake of the exogenous DNA. The plant expression vector pAB6 containing bar gene as a selectable marker for the herbicide bialaphos resistance and GUS (uidA) gene as a reporter gene was used for transformation. No selection pressure was conducted during the four-week callus induction period. Induced calli were transferred to a modified MS medium with 1 mg l(-1) bialaphos for regeneration, followed by selection on 2 mg l(-1) bialaphos for rooting. Three regenerated putative transgenic events were evaluated for the integration and stable expression of both genes and results indicated that this modified procedure of laser-mediated transformation can be successfully used in transforming wheat.     

Fertile transgenic Brachiaria ruziziensis (ruzigrass) plants by particle bombardment of tetraploidized callus

We have produced transgenic plants of the tropical forage crop Brachiaria ruziziensis (ruzigrass) by particle bombardment-mediated transformation of multiple-shoot clumps and embryogenic calli. Cultures of multiple-shoot clumps and embryogenic calli were induced on solidified MS medium supplemented with 0.5mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 2mg/L 6-benzylaminopurine (BAP) or 4mg/L 2,4-D and 0.2mg/L BAP, respectively. Both cultures were bombarded with a vector containing an herbicide resistance gene (bar) as a selectable marker and the β-glucuronidase (GUS) reporter gene. Sixteen hours after bombardment, embryogenic calli showed a significantly higher number of transient GUS expression spots per plate and callus than multiple-shoot clumps, suggesting that embryogenic callus is the more suitable target tissue. Following bombardment and selection with 10mg/L bialaphos, herbicide-resistant embryogenic calli regenerated shoots and roots in vitro, and mature transgenic plants have been raised in the greenhouse. Polymerase chain reaction (PCR) and DNA gel blot analysis verified that the GUS gene was integrated into the genome of the two regenerated lines. In SacI digests, the two transgenic lines showed two or five copies of GUS gene fragments, respectively, and integration at different sites. Histochemical analysis revealed stable expression in roots, shoots and inflorescences. Transgenic plants derived from diploid target callus turned out to be sterile, while transgenics from colchicine-tetraploidized callus were fertile.     

基因枪法获得逆境诱导转录因子DREB1A转基因小麦的研究

以小麦品种H6756和藁城8901作为基因枪转化的靶材料,取其护颖至雌雄蕊原基形成期的幼穗,用含逆境诱导转录因子DREB1A和bar基因的质粒pAHC25轰击胚性愈伤组织,在分别含有5mgL和10mgLBasta溶液的培养基上进行筛选。得到的抗性愈伤组织在不含Basta溶液的培养基上再生培养,获得218棵再生植株。田间涂抹浓度为100mgL的Basta溶液检测后,对抗性植株作PCR检测,获得54棵再生植株。通过对其中20株T1代的PCR和Southern杂交分析,已获得14株含DREB1A和bar基因的转基因小麦植株,其中H675613株,藁城89011株。     

Glyphosate-tolerant CP4 and GOX genes as a selectable marker in wheat transformation

The lack of alternative selectable markers in crop transformation has been a substantial barrier for commercial application of agricultural biotechnology. We have developed an efficient selection system for wheat transformation using glyphosate-tolerant CP4 and GOX genes as a selectable marker. Immature embryos of the wheat cultivar Bobwhite were bombarded with two separate plasmids harboring the CP4/GOX and GUS genes. After a 1 week delay, the bombarded embryos were transferred to a selection medium containing 2 mM glyphosate. Embryo-derived calli were subcultured onto the same selection medium every 3 weeks consecutively for 9–12 weeks, and were then regenerated and rooted on selection media with lower glyphosate concentrations. Transgenic plants tolerant to glyphosate were recovered. ELISA assay confirmed expression of the CP4 and GOX genes in R₀ plants. Southern blot analysis demonstrated that the transgenes were integrated into the wheat genomes and transmitted to the following generation. The use of CP4 and GOX genes as a selectable marker provides an efficient, effective, and alternative transformation selection system for wheat.     

An efficient wheat transformation procedure: transformed calli with long-term morphogenic potential for plant regeneration

 A method for producing large numbers of transgenic wheat plants has been developed. With this approach, an average of 9.7% of immature embryo explants were transformed and generated multiple self-fertile, independently transformed plants. No untransformed plants, or escapes, were regenerated. This transformation procedure uses morphogenic calli derived from scutellum tissue of immature embryos of Triticum aestivum cv. Bobwhite co-bombarded with separate plasmids carrying a selectable marker gene (bar) and a gene of interest, respectively. Transformed wheat calli with a vigorous growth phenotype were obtained by extended culture on media containing 5.0 mg/l bialaphos. These calli retained morphogenic potential and were competent for plant regeneration for as long as 11 months. The bar gene and the gene of interest were co-expressed in T0 progeny plants. This wheat transformation protocol may facilitate quantitative production of multiple transgenic plants and significantly reduce the cost and labor otherwise required for screening out untransformed escapes. Received: 15 June 1998 / Revision received: 6 April 1999 / Accepted: 26 April 1999     

大叶种胡椒实生苗茎尖培养和合子胚培养研究

利用各种表面消毒方法对采自海南岛三个地区的胡椒大田植株的外植体进行消毒试验,由于内源性污染,除胡椒成熟种子外,其它各种大田外植体的表面消毒均未能成功。以胡椒成熟种子无菌萌发的实生苗茎尖作外植体,在1/2MS(MS或B5)+1.5mg/LBA+0～0.2mg/LIAA(或NAA)上可实现丛生芽增殖。茎尖水平或竖直接种方法显著影响茎尖的增殖;水平接种茎尖的生长和增殖效果优于竖直茎尖接种方式。茎尖增殖率随BA浓度的增加而提高,但BA浓度大于2.0mg/L时会使苗芽的质量降低,愈伤组织产生严重,苗芽细小,抽出不明显,颜色发黄甚至变白。附加或不附加100mg/LAdSO4对丛生芽增殖没有明显影响。生根培养基以1/2MS+1.0mg/LIBA+0.5～1.0mg/LIAA为最优,生根率可达100%;在细沙∶土∶椰糠(1∶1∶1)的基质中常规炼苗,成活率可达98%以上。液体纸桥法对胡椒种胚进行培养,在不附加任何生长调节物质的培养基(MS、B5或SH)上只产生单苗,而在附加不同种类和不同浓度的生长调节物质的培养基上则诱导形成愈伤组织,但未能实现分化;以胡椒无菌萌发的实生苗胚轴和叶片切段作外植体进行培养,较易诱导产生愈伤组织,但难以实现分化。