PSAG12-ipt嵌合基因转化马铃薯体系的研究

以根癌农杆菌介导法将PSAG12-ipt嵌合基因导入马铃薯栽培品种,对影响马铃薯遗传转化的多种因素进行系统研究.结果表明:马铃薯茎段分化效率高于叶片,马铃薯愈伤诱导和芽分化最适培养基为MS+6-BA 0.25mg/L+NAA 0.25mg/L+2,4-D 0.25mg/L,添加1%Na2SO3能有效防止褐化;茎段愈伤诱导和分化苗生根最适的Kan浓度分别为50mg/L和75mg/L;外植体预培养2d,OD600为0.2～0.5的农杆菌浓度侵染8min、共培养3d后进行选择培养能有效地提高植株再生能力.用PSAG12和ipt双重PCR检测再生植株,阳性转化率为65.8%.Southern blotting结果表明,转基因植株多以单拷贝形式整合进马铃薯基因组中.     

液泡转化酶反义基因对番茄的遗传转化

以'中蔬4号'番茄的子叶为试材,通过农杆菌介导法遗传转化,将液泡转化酶反义基因导入再生植株,经PCR和Southern斑点杂交检测证明,5株转化植株基因组中整合有目的基因.遗传转化最佳条件为:在附加1.5 mg/L 6-BA和0.1 mg/L IAA的MS培养基上再生培养,外植体预培养2 d,菌液浓度OD600=0.5,侵染时间5 min,共培养2 d.遗传转化后,对整合有目的基因的再生番茄叶片液泡转化酶活性测定,表明液泡转化酶活性明显受到抑制.获得的转基因植株为进一步研究液泡转化酶基因的功能奠定了基础.     

偃伏梾木组织培养及再生体系的建立(简报)

本文以偃伏株木(Cornus stolonifera)叶片为外植体,建立了其叶片再生体系.同时系统地研究了离体再生芽及丛生芽分化增殖的适宜培养基、不定根诱导的关键因子以及再生芽生根后植株移栽成活的影响因素.叶片外植体在添加0.5 mg/L 6-BA和1.0 mg/L IBA的1/2 MS培养基上再生频率达100%,平均每个外植体上再生芽数为5.0±0.7.不定芽在添加0.5 mg/L 6-BA和0.25 mg/LIBA的1/2 MS培养基上能有效增殖.再生芽在添加0.5 mg/L IBA的1/2 MS培养基上生根效果最佳.在叶片再生过程中选取典型组织进行扫描电镜观测,进一步证实了偃伏株木叶片直接体细胞胚发生过程.用携带有gus基因表达载体的农杆碱型EHA105农杆菌菌株浸染叶片外植体,能观察到其中gus基因的瞬时表达.     

中国传统菊花品种‘小林静’再生及转化体系的建立

以中国传统菊花品种‘小林静’叶片为外植体,建立了‘小林静’较好的再生体系及遗传转化体系.结果表明,‘小林静’叶盘最适不定芽分化培养基为MS+2.0 mg/L 6-BA+1.5 mg/L NAA,不定芽分化率为92.76％,平均再生不定芽数为2.3767个;试管苗最佳生根培养基为1/2MS,生根率达100％.移栽采用灭菌的蛭石,再生苗移栽成活率达90％以上.采用根癌农杆菌C58C1介导的叶盘转化法进行‘小林静’的遗传转化试验,农杆菌OD600=0.5-0.6,侵染10 min后,将叶片外植体接种到MS+2.0 mg/L 6-BA+1.5mg/L NAA的培养基中黑暗共培养2d,之后转接到附加10 mg/L硫酸卡那霉素和400 mg/L羧苄青霉素的分化筛选培养基中进行转化细胞的筛选,待长出抗性芽后转接至生根培养基中进行培养,最终建立了菊花品种‘小林静’的遗传转化体系.     

‘光叶蔷薇’器官间接再生体系的建立及GUS基因转化的初步研究

以‘光叶蔷薇’(Rosa wichuriana‘Basye's thornless’)无菌苗的顶生幼嫩小叶为外植体,探讨了其愈伤组织诱导及植株再生的方法。结果表明,高浓度的生长素NAA能诱导外植体产生愈伤组织;由NAA诱导的愈伤组织在附加TDZ的MS培养基上,先暗培养再进行光照培养可直接分化出不定芽。诱导愈伤组织的最佳NAA浓度是7.0 mg/L、暗培养时间为10 d,而最佳分化培养基是MS+5.0 mg/L TDZ+30 g/L葡萄糖+2.5 g/L GEL,分化率达18.34%。以诱导产生的愈伤组织为侵染受体,初步建立了‘光叶蔷薇’GUS基因转化体系。农杆菌菌液浓度OD600值为0.5、侵染30 min、共培养2 d、乙酰丁香酮的浓度为50μmol/L是‘光叶蔷薇’愈伤组织转基因的最优条件。     

川芎高频再生体系的建立

为建立川芎(Ligusticum chuanxiong Hort.)高频再生体系,优化了诱导和分化培养基及培养条件。以叶柄为外植体,以MS为基本培养基,KT 2.0 mg/L+IAA 0.5 mg/L的激素组合对不定芽分化最有利。在此基础上,针对外植体来源、培养条件和愈伤组织继代时间3个因素进行优化。结果表明:采用川芎无菌苗叶柄作为外植体,黑暗条件下诱导出愈伤组织,再在光照下继代培养15 d后转入分化培养基中对不定芽诱导最为有利,分化率为44.4%。分化后得到的不定芽在含NAA 0.5 mg/L和IBA 0.5 mg/L的 1/2MS培养基上生根率达90%,移栽存活率为95%。     

‘光叶蔷薇’器官间接再生体系的建立及GUS基因转化的初步研究

以‘光叶蔷薇’（Rosa wichuriana ‘Basye’s thornless’）无菌苗的顶生幼嫩小叶为外植体,探讨了其愈伤组织诱导及植株再生的方法。结果表明,高浓度的生长素NAA能诱导外植体产生愈伤组织;由NAA诱导的愈伤组织在附加TDZ的MS培养基上,先暗培养再进行光照培养可直接分化出不定芽。诱导愈伤组织的最佳NAA浓度是7.0 mg/L、暗培养时间为10 d,而最佳分化培养基是MS + 5.0 mg/L TDZ + 30 g/L葡萄糖 + 2.5 g/L GEL,分化率达18.34%。以诱导产生的愈伤组织为侵染受体,初步建立了‘光叶蔷薇’GUS基因转化体系。农杆菌菌液浓度OD₆₀₀值为0.5、侵染30 min、共培养2 d、乙酰丁香酮的浓度为50 μmol/L是'光叶蔷薇’愈伤组织转基因的最优条件。     

川芎高频再生体系的建立

为建立川芎(Ligusticum chuanxiong Hort.)高频再生体系,优化了诱导和分化培养基及培养条件.以叶柄为外植体,以MS为基本培养基,KT2.0 mg/L+ IAA0.5mg/L的激素组合对不定芽分化最有利.在此基础上,针对外植体来源、培养条件和愈伤组织继代时间3个因素进行优化.结果表明:采用川芎无菌苗叶柄作为外植体,黑暗条件下诱导出愈伤组织,再在光照下继代培养15d后转入分化培养基中对不定芽诱导最为有利,分化率为44.4％.分化后得到的不定芽在含NAA0.5 mg/L和IBA 0.5 mg/L的1/2MS培养基上生根率达90％,移栽存活率为95％.     

百合鳞片的诱导分化及遗传转化效率分析

基因工程是改良百合性状的重要手段,建立高效稳定的遗传转化体系是百合转基因研究的基础。以百合地下茎鳞片为外植体,筛选并优化百合的直接和间接再生体系;把含枸杞GR(Glutathione reductase)基因和筛选基因NPTII的载体,利用农杆菌转化法对鳞片和愈伤组织进行转基因操作,采用正交试验,优化转化条件以建立适合不同受体的遗传转化体系。结果表明,各阶段最优培养条件分别为:鳞片诱导和膨大MS+2mg/L 2,4-D(2,4-二氯苯氧乙酸)+0.1mg/L NAA(萘乙酸)+ 90g/L蔗糖;鳞片直接分化MS+1.0mg/L 6-BA(6-苄氨基嘌呤)+0.2mg/L NAA+ 30g/L蔗糖,间接分化MS+2.5mg/L 2,4-D +0.4mg/L TDZ(噻重氮苯基脲)+60g/L蔗糖;百合鳞片的Kana(卡那霉素)选择压为100mg/L,愈伤组织75mg/L。遗传转化体系条件为:鳞片,农杆菌OD₆₀₀=0.6,预培养3d,侵染40min,As(乙酰丁香酮)200μmol/L,阳性植株转化率为17.50%;鳞片分化愈伤组织,农杆菌OD₆₀₀,预培养5d,侵染40min,As 200μmol/L,阳性植株转化率为12.60%。     

香石竹毛状根诱导、离体培养及其植株再生

为了探讨利用发根农杆菌遗传转化所产生的毛状根来创新香石竹种质的可能性,本文采用叶盘法,建立了发根农杆菌Agrobacterium rhizogenes对香石竹Dianthus caryophyllus L.叶片外植体的遗传转化及其植株再生体系。结果表明,发根农杆菌ATCC15834感染香石竹幼嫩叶片外植体12 d后,从叶片外植体切口中脉处产生白色毛状根,21 d后约90%的叶片外植体产生毛状根。所获得的无菌毛状根能在无外源激素的MS固体和液体培养基中快速自主生长。PCR扩增和硅胶薄层层析结果显示发根农杆菌Ri质粒的rol B和rol C基因以及冠瘿碱合成酶基因已在香石竹毛状根基因组中整合并得到表达。将毛状根置于MS+6-BA 1.0-3.0 mg/L+NAA 0.1-0.2 mg/L中培养15 d后产生淡黄绿色的疏松愈伤组织。愈伤组织不定芽分化的最适培养基为MS+6-BA 2.0 mg/L+NAA 0.02 mg/L,培养6周后不定芽分化率为100%;平均每个愈伤组织产生30-40个不定芽;将不定芽转至1/2 MS或1/2 MS+0.5 mg/L NAA的培养基中10 d后产生不定根,发育成再生植株。再生植株移植于栽培基质中20 d后,成活率达95%以上。     

Pathogen resistant Transgenic Plant from Dwarfing Rootstock of Cherry by Introducing Antibacterial Polypeptide Genes

A shoot regeneration system of high frequency from shoot of Chinese cherry ( Prunus pseudocerasus Lindl. ) dwarfing rootstock was established and 19 transformed plants were obtained from the dwarfing rootstock by introducing gus gene and antibacterial polypeptide genes, using Agrobacteriuan tumefaciens (Smith et Townsend) Corm as mediator. The results of Southern blot analysis proved that antibacterial polypeptide gene was integrated into the cherry genome. The results of tumor test, X-gluc reaction and bacterial-resistant test of leaf extract against Agrobacterium tumefaciens C58 indicated that antibacterial polypeptide gene may be expressed efficiently in the transformed plant. The tube shoot was characteristic in its resistance to root nodule disease. This study on the characteristics of germ line transformation of shoot meristem suggested that it was a highly efficient transformation system.     

农杆菌介导GUS基因对多年生黑麦草转化的研究

通过检测愈伤组织中GUS基因的瞬间表达,研究农杆菌LBA4404/pCAMBIA1301介导多年生黑麦草的转化体系。通过对多年生黑麦草瞬间表达率的比较,确立了其遗传转化的最佳优化条件。研究发现,多年生黑麦草不同品种的转化率在25%~45%之间变化。多年生黑麦草遗传转化最佳优化条件是预培养10d的胚性愈伤组织、浓度为0.5~0.8OD的农杆菌菌液以及2d共培养时间。在共培养基中添加100μmol/L乙酰丁香酮能有效地提高植物瞬间表达率。两种侵染处理方法比较结果为滤纸滴加法比浸泡法更优。转化后对愈伤组织的干燥处理能抑制农杆菌过度繁殖,能改善愈伤状态,有利于提高转化率。     

抗菌肽基因转化樱桃矮化砧木获得抗根瘤病的转基因植株

建立了樱桃（PrunuspseudocerasusLindl．）矮化砧木茎尖高频再生系统,并利用根癌土壤杆菌（Agrobacteriumtumefaciens（SmithetTownsend）Conn）介导将gus及抗菌肽基因导入樱桃矮化砧木,获得19个转化株系。经Southernblot检测证明,抗菌肽基因已整合到樱桃的基因组。转基因植株接瘤实验、gus基因表达产物的颜色反应及叶片提取液对根癌土壤杆菌C58的抑菌实验表明,抗菌肽基因在转化植株中可能已得到有效表达,试管苗具有明显的抗根瘤病特性。还研究了茎尖分生组织的种质转化特点,结果表明它是一个较好的转化系统,可获得较高的转化频率。     

Transgenic superroots of Lotus corniculatus can be regenerated from superroot-derived leaves following Agrobacterium-mediated transformation

Super-growing roots (superroots; SR), which have been established in the legume species Lotus corniculatus, are a fast-growing root culture that allows continuous root cloning, direct somatic embryogenesis and mass regeneration of plants under entirely growth regulator-free culture conditions. These features are unique for non-hairy root cultures, and they are now stably expressed since the culture was isolated more than 10 years ago (1997). Attempts to achieve direct and stable transformation of SR turned out to be unsuccessful. Making use of the supple regeneration plasticity of SR, we are reporting here an indirect transformation protocol. Leaf explants, derived from plants regenerated from SR, were inoculated with Agrobacterium tumefaciens strain LBA4404 harboring the binary vector pBI121, which contains the neomycin phosphotransferase II (NPTII) and beta-glucuronidase (GUS) genes as selectable and visual markers, respectively. After co-cultivation, the explants were selected on solidified MS medium with 0.5mg/L benzylamino purine (BAP), 100mg/L kanamycin and 250mg/L cefotaxime. Kanamycin-resistant calli were transferred to liquid rooting medium. The newly regenerated, kanamycin-resistant roots were harvested and SR cultures re-established, which exhibited all the characteristics of the original SR. Furthermore, kanamycin-resistant roots cultured onto solidified MS medium supplemented with 0.5mg/L BAP produced plants at the same rate as control SR. Six months after gene transfer, PCR analysis and histochemical locating indicated that the NPTII gene was integrated into the genome and that the GUS gene was regularly expressed in leaves, roots and nodules, respectively. The protocol makes it now possible to produce transformed SR and nodules as well as transgenic plants from transformed SR.     

反义磷脂酶Dγ基因转化毛白杨的研究

利用根癌农杆菌介导法将反义磷脂酶Dγ基因（PLDγ）转入BT-18号三倍体毛白杨。本研究建立了三倍体毛白杨的高频再生系统,对传统农杆菌侵染方法进行了改良,通过抗生素筛选获得大量抗性植株。对抗性植株进行了PCR和PCR-Southern杂交鉴定,证实反义基因,已整合入杨树核基因组中。通过对转基因植株的耐盐性鉴定,获得一批可耐0.7%NaCl的植株。 Abstract:Antisense Phospholipase Dγ（ PLDγ）gene was introduced into Populus tomentosa mediated by Agrobactrium tumefaciens.The young leaves of triploid populus were used as the material and the regeneration system of high frequency has been established.We have developed the traditional transgene method by Agrobactrium trmefaciens and obtained many transgenic plants of anti-PLDγ gene.Tests showed that the transgenic plants can grow well on the culture medium with 0.7% NaCl.     

荔枝生物技术研究进展

综述了离体培养、有利基因的克隆及遗传转化等生物技术的三个方面在荔枝研究中的应用进展。已有研究者分别建立了花粉培养、叶片培养、幼胚培养等获得植株的再生体系,克隆了部分荔枝基因,建立了基因枪与根癌农杆菌转化体系。这些研究为荔枝生物技术育种提供了基础。     

Early events in Agrobacterium-mediated genetic transformation of citrus explants

BACKGROUND AND AIMS: Genetic transformation of plants relies on two independent but concurrent processes: integration of foreign DNA into plant cells and regeneration of whole plants from these transformed cells. Cell competence for regeneration and for transformation does not always fall into the same cell type/developmental stage, and this is one of the main causes of the so-called recalcitrance for transformation of certain plant species. In this study, a detailed examination of the first steps of morphogenesis from citrus explants after co-cultivation with Agrobacterium tumefaciens was performed, and an investigation into which cells and tissues are competent for regeneration and transformation was carried out. Moreover, the role of phytohormones in the co-cultivation medium as possible enhancers of gene transfer was also studied. METHODS: A highly responsive citrus genotype and well-established culture conditions were used to perform a histological analysis of morphogenesis and cell competence for transformation after co-cultivation of citrus epicotyl segments with A. tumefaciens. In addition, the role of phytohormones as transformation enhancers was investigated by flow cytometry. KEY RESULTS: It is demonstrated that cells competent for transformation are located in the newly formed callus growing from the cambial ring. Conditions conducive to further development of this callus, such as treatment of explants in a medium rich in auxins, resulted in a more pronounced formation of cambial callus and a slower shoot regeneration process, both in Agrobacterium-inoculated and non-inoculated explants. Furthermore, co- cultivation in a medium rich in auxins caused a significant increase in the rate of actively dividing cells in S-phase, the stage in which cells are more prone to integrate foreign DNA. CONCLUSIONS: Use of proper co-cultivation medium and conditions led to a higher number of stably transformed cells and to an increase in the final number of regenerated transgenic plants.     

"全明星"草莓叶片再生体系的建立

以“全明星”草莓叶片为外植体,探讨植物激素、基本培养基、pH值、叶片放置方式等对叶片再生的影响,得出在MS＋BA2．0mg／l＋NAA0．2mg／l的培养基上,叶片不定芽再生率达64％,最适pH值为5．8,叶片背面接触培养基有利于芽的再生。建立了“全明星”叶片再生系统,为草莓的微繁和基因转化打下基础。     

Shoot Regeneration from Cultured Leaf Explants of Lycium barbarumand Agrobacterium-Mediated Transformation1

A method for fast plant regeneration via organogenesis directly from Lycium barbarumleaf explants has been developed. The key factor for shoot regeneration was the presence of benzyladenine (BA) in the medium. NAA could only induce root formation and explant callusing. Murashige and Skoog (MS) medium supplemented with 2 mg/l BA and 0.5 mg/l NAA is the most efficient condition for shoot formation, with up to 92.6% shoot regeneration and no callus formation. All adventitious shoots cultured on MS medium supplemented with 1 mg/l IAA formed an extensive root system. Regenerated plants were morphologically normal and were also proved to be diploid (2n = 24). Using the optimized regeneration system, the genetic transformation of L. barbarumwas carried out mediated by Agrobacterium tumefaciensEHA101(pIG121Hm). 11.8% leaf explants produced kanamycin-resistant shoots after infection by A. tumefaciens.The putative transgenic nature of plants was confirmed by GUS assay and PCR analysis. Expression of the nptIIgene in the regenerated plants was also detected by observing the callus formation by leaf pieces on MS medium containing 0.2 mg/l 2,4-D and 0–100 mg/l kanamycin.     

根癌农杆菌介导D32基因

以烟草品种'中烟99'的无菌苗叶片为转化受体材料,通过根癌农杆菌C58C1介导对大豆中克隆的抗逆性基因D32进行转化,获得了抗卡那霉素的再生植株,并对转化植株进行了PCR检测.结果表明,烟草叶片分化和再生的卡那霉素选择压力为150 mg/L;外植体预培养对转化率有影响;优化的烟草转化方法是:经预培养2 d的外植体用OD600值为0.7的菌液侵染5 min, 共培养2 d后用无菌水冲洗5～6次,羧苄青霉素(Cb)和头孢霉素(Cef)浓度为400 mg/L的脱菌液浸泡120 min,超净工作台上吹风60 min,于筛选分化培养基生长50 d,可获得26.7%卡那抗性苗.对抗性植株经PCR检测证明,外源D32基因已初步整合到烟草基因组中.