Effect of the Antisense BcMF12 Driven by the BcA9 Promoter on Gene Silencing in Brassica campestris L. ssp. chinensis

The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi （Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis） and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.     

BcA9启动子调控的反义BcMF12对白菜基因沉默的效果

 【目的】探讨花药绒毡层特异启动子BcA9调控的反义BcMF12基因对白菜（Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis）基因沉默的效果,明确其对花粉发育的影响。【方法】在从白菜花蕾cDNA中克隆BcMF12基因的保守区段的基础上,将白菜花药特异表达启动子BcA9与反义BcMF12基因融合,构建反义表达载体,并经农杆菌介导导入到白菜基因组中,利用抗生素筛选和分子检测筛选出转基因植株。【结果】PCR和Southern检测结果表明,BcA9启动子驱动的反义BcMF12-GUS报告基因已整合到白菜基因组中;Northern杂交显示转基因植株花蕾和花中的BcMF12在mRNA水平的表达明显受到抑制,而且花粉萌发率显著下降。【结论】BcA9调控的反义BcMF12基因明显抑制了BcMF12的表达,从而影响白菜花粉的发育。     

白菜雄性不育相关基因BcMF4的反义RNA验证

根据普通白菜(Brassica campestris ssp.chinensis var.communis)雄性不育相关基因BcMF4的cDNA序列设计特异引物,从普通白菜花蕾cDNA中扩增出607 bp的片断,然后将该片段连接至双元载体pBI12l中,得到反义RNA植物表达载体并导入农杆菌LBA4404菌株中;通过组织培养途径转化菜心(B.campestris ssp.chinensis var.parachinensis),得到了12株转基因植株,其中5株的43.7%的花粉为缩小空瘪畸形,29.6%的花粉缺乏生活力,而且其花粉离体萌发率降低至24.7%.结果表明,反义RNA技术沉默BcMF4基因导致了菜心转基因植株的部分花粉发育不良,BcMF4基因在普通白菜和菜心等花粉发育中起着重要作用.     

白菜雄性不育相关基因BcMF3功能的反义RNA验证

为了研究白菜等十字花科植物花粉发育及雄性不育发生的机理,根据编码果胶甲酯酶的白菜雄性不育相关基因BcMF3的cDNA序列设计特异引物,从普通白菜(Brassica campestris ssp.chinensis var.communis,syn.B.rapa ssp.chinensis var.communis)花蕾cDNA中扩增出458 bp的片断,构建BcMF3的反义RNA植物表达栽体,然后转化菜心(B. campestris ssp.chinensis var.parachinensis).研究发现,31.3%菜心转基因植株花粉表现出畸形,而且只有部分花粉具有活力,花粉离体萌发率降低为31.6%,其花药果胶甲酯酶活性降低了12.8%.上述结果表明BcMF3基因与普通白菜和菜心等白菜植物的花粉发育密切相关.     

白菜雄性不育相关基因BcMF3和BcMF4的A9启动子的基因沉默植物表达载体的构建

以白菜(Brassica campestris ssp.chinensis,syn.B.rapa ssp.chinensis)雄性不育相关基因BcMF3和BcMF4为沉默对象,利用绒毡层组织特异性的A9启动子,构建了反义RNA、RNA干涉和双价反义RNA植物表达载体。结果表明,经过一系列分子操作,获得了A9启动子和目的基因片段,并利用它们构建了5个基因沉默植物表达载体,可用于基因功能验证。     

Bc A 9 - B a r n a s e转基因雄性不育烟草的获得

利用农杆菌介导法将大白菜启动子BcA9与Barnase的融合基因对烟草叶片进行遗传转化,经含Basta的筛选培养基连续筛选,获得了转基因再生植株.转基因植株经PCR扩增,表明BcA9-Barnase基因已整合到烟草基因组中.对转基因植株和野生型植株的花药发育进行细胞学比较观察,显示野生型植株的花药发育正常,花粉粒形态正常,活力高;而转基因植株则发生花药绒毡层细胞提前降解,花粉母细胞退化,成熟花药中无正常花粉粒产生等系列现象.转基因烟草植株最终表现为花药瘦小、自交不能正常结籽等.同时,在高温条件下转基因植株不育性稳定,无育性恢复现象.     

Expression of an Antisense BcMF3 Affects Microsporogenesis and Pollen Tube Growth in Arabidopsis

In an effort to provide some information relevant to the molecular mechanism of genic male sterility in plants, BcMF3 gene that encodes a pectin methylesterase was isolated from the fertile B line of Chinese cabbage-pak-choi （Brassica rapa ssp. chinensis, syn. B. campestris ssp. chinensis）. In the present paper, a 455-bp antisense cDNA fragment of BcMF3 was introduced to binary vector pB1121, and then was mobilized into Agrobacterium tumefaciens strain LBA4404. The A. tumefaciens harboring the BcMF3 antisense fragment was transformed to Arabidopsis thaliana by floral dip. Scanning electronic microscopy examination demonstrated that 47.8% of BcMF3 antisense pollen grains exhibited abnormal shape, which might lead to decreased germination of pollens, suggesting that the product of BcMF3 gene plays an important role during microsporogenesis. The evidence on burst of 45.7% of BcMF3 antisense pollen tubes in vitro and a majority of BcMF3 antisense pollens restricted within the stigmatic tissue revealed that BcMF3 is involved in aiding the growth of pollen tubes. The results suggest that BcMF3 acts at both stages of microsporogensis and pollen tube growth.     

Molecular Cloning and Characterization of Pollen Development Related Gene RsMF2 from Raphanus sativus L.

In the paper, the full length cDNA of RsMF2 gene, homologous with the BcMF2 gene encoding pollen-specific polygalacturonase of Chinese cabbage-pak-choi (Brassica campestris L. ssp. chinensis Makino) was cloned from Raphanus sativus L. cv. Yuanbai by PCR, with a pair of primer designed according to the coding sequence of BcMF2. The largest opening reading frame of RsMF2 gene is 1 266 bp in length and encodes a protein of 421 amino acids with a predicted molecular mass of 43.9 kDa. Sequence analysis revealed that it has three potential N-glycosylation sites and one polygalacturonase active position (RVTCGPGHGLSVGS). And the first 32 amino acids of the predicted RsMF2 protein form a N-terminal hydrophobic domain which displays the properties of a signal peptide. The predicted secondary structure composition for the protein has 6.9% helix, 42.0% sheet and 51.1% loop. Four domains which are highly conserved in the whole plant and fungal PGs is present in RsMF2. Phylogenetic analysis showed that RsMF2 falls into the category of clade-C, which includes PGs related to pollen. These results indicate that RsMF2 may act as polygalacturonase related to pollen development.     

Measurement of Some Physiological and Biochemical Indexes of the Antisense Fragment of CYP86MF Gene Transgenic Male Sterile Plantlets in Chinese Cabbage-Pak-Choi

In order to study the mechanism of the transgenic male sterility induced by the antisense fragment of gene CYP86MF, some physiological and biochemical indexes were compared between the transgenic plantlets of Chinese cabbage-pak-choi (Brassica campestris L. ssp. chinensis Makino) and their controls.Results showed that there was significant difference between content of the endogenous hormones in leaves and floral buds. GA3 contents in leaves of the transgenic plantlets of B. campestris L. ssp. chinensis Makino cv.Shanghai-qing and cv. Youqing were reduced by 31.72 and 46.88% respectively as compared with those of their controls, and GA3 contents in floral buds of them were reduced by 62.92 and 80.57 % respectively. In addition, ZT contents in leaves of cv. Shanghai-qing and cv. Youqing were reduced by 11.81 and 181.20%respectively as compared with those of their controls and those in floral buds were reduced by 105.94 and 128.75% respectively. But, ABA content in transgenic plantlets was significantly higher than that in nontransgenic plantlets. However, differences among respiratory rate and cyanide-resistant respiratory rate, the photosynthesic rate and the content of total flavones in floral buds were not significant. In this study, the results indicated that the gene CYP86MF might be one of the key functional genes to control fertility of Chinese cabbage.     

反义CYP86MF基因植物表达载体的构建及其对白菜的转化

在获得一个与白菜核雄性不育相关的编码细胞色素P450(CYP450)的基因CYP86MF的基础上,采用PCR技术在该基因的内部第901个碱基至第1338个碱基之间设计引物,扩增出438 bp序列作为反义基因片段.把该反义片段连接至pBI121双元载体质粒上得到CaMV35S组成型启动子的表达载体pBI35S-AMF,随后利用"三亲杂交"法将pBI35S-AMF质粒转入农杆菌LBA4404和EHA105两个菌株中.PCR扩增和酶切鉴定结果表明,所构建的反义CYP86MF基因植物表达载体pBI35S-AMF是正确的,并已成功导入了根癌农杆菌中.随后,按照已建立的遗传转化体系对‘上海青'白菜进行了转化,并获得130了多株转化再生植株.     

水稻OsHOX6启动子的组织特异性表达

【目的】研究水稻HD-ZipⅠ转录因子家族的成员OsHOX6基因启动子的表达。【方法】通过构建水稻OsHOX6基因启动子与GUS基因融合表达载体,利用农杆菌(Agrobacterium)介导,以未成熟水稻胚作为试验材料,转化到水稻IR64,通过PCR检测和潮霉素抗性筛选出阳性的转基因植株,从不同组织取样品,进行X-Gluc染色并观察。【结果】转基因植株的叶、根、茎、花等器官经过X-Gluc染色后,主要在侧根、花粉以及组织损伤部分出现蓝色斑点,其它组织均未检测出蓝色斑点,观察根解剖结构,绿色斑点集中在根内皮层。【结论】 水稻OsHOX6基因启动子能够驱动GUS基因,在转基因水稻侧根和花粉上特异表达。     

油菜PEP基因的克隆及PEP反义基因的构建

丙酮酸羧化酶（ Ｐ Ｅ Ｐ）是控制油菜蛋白质／油脂含量比例的一个关键酶⒚本研究用 Ｐ Ｃ Ｒ 法扩增出了 Ｐ Ｅ Ｐ 基因片段,并将其 克隆到 ｐ Ｂ Ｓ Ｓ Ｋ＋ 的 Ｓｍ ａ Ⅰ位点⒚ Ｄ Ｎ Ａ 序列分析表 明克隆片段 的长度为 ５３０ｂｐ,其序列与报道序列相同⒚将该 Ｐ Ｅ Ｐ基因 片段反向插入 ｐ Ｉ Ｇ１２１ 质粒,构建了带 Ｐ Ｅ Ｐ 反义基因的超级双元载体并进行油菜的转化,目前已获得转基因植株⒚     

烟草花叶病毒移动蛋白基因转化烟草及在转基因烟草中的表达

根据烟草花叶病毒蚕豆株系（TMV-B）的已知序列合成引物，经PCR扩增获得TMV-B的移动蛋白（MP）基因。该基因测序验证后，分别以正、反向克隆到植物表达载体pBI121中，并置于CaMV35S启动子控制之下，通过三亲交配及叶盘转化，将MP基因导入烟草。经卡那霉素抗性筛选，PCR扩增，Southern点杂交,Northern点杂交及Westernblot检测，获得了正义表达MP基因及反义表达MP基因的转基因烟草，分别命名为pTMP（+）烟草和pTMP（-）烟草。     

小麦花粉电穿孔转化因素优化和转基因植株获得及鉴定

[目的]通过优化电穿孔转化技术主要参数,得到候选转基因植株,探索普通小麦(Triticum aestivum L.)电穿孔遗传转化体系.[方法]以冬小麦品种济麦19为受体,GUS为外源基因,将扬花期成熟花粉以最适电场强度和操作温度进行电穿孔处理后,人工授粉济麦19,最终收获种子;利用PCR技术、Southern技术、化学染色方法对T1、T2植株进行鉴定.[结果]电穿孔转化以电场强度6 kV·cm-1、冰上处理花粉,花粉密度为5×106个/mL,以及去雄后第5天授粉为最佳参数;Southern杂交检测结果表明,T2阳性植株的2个株系检测到杂交信号,同时其幼根、叶片等组织经GUS表达活性的组织化学染色检测,呈现蓝色反应.[结论]利用小麦花粉电穿孔转化法可以成功将外源基因整合到小麦基因组中并稳定遗传至T2,且外源基因GUS能够得到表达.     

Agrobacterium-mediated Transformation of Rice (Oryza sativa L.) with Atrazine Chlorohydrolase Gene (atzA)

Atrazine chlorohydrolase gene (atzA) was cloned from Arthrobacter sp. AD1. A plant expression plasmid was constructed under the control of CaMV35s promoter and was used in rice transformation. The target gene was successfully introduced into mature embryos of a japonica rice cultivar Jindao 107 by Agrobacterium- mediated transformation and hundreds of transgenic plants were obtained. The exogenous atzA gene in the transgenic plants that expressed atrazine resistance was confirmed by Southern blot hybridization. The resistance experiments by spraying transgenic rice plants with 0.133% atrazine shown that most of the transgenic rice plants exhibited the resistance to herbicide atrazine. The segregation of exogenous atzA gene in T1 progeny corresponded to the Mendelian ratio.     

农杆菌介导的薹菜遗传转化体系研究

以薹菜子叶-子叶柄为外植体,研究了根癌农杆菌介导的遗传转化技术。用含GUS和NPTⅡ基因的农杆菌侵染子叶-子叶柄,获得了具有卡那霉素抗性的再生植株。再生植株经GUS组织染色,证实外源基因转化到植物基因组中。卡那霉素敏感性测定结果表明,当培养基中含卡那霉素（Km）15 mg/L时,非转化再生植株全部白化。转基因抗性芽筛选的适宜的卡那霉素浓度为10 mg/L。     

BcMF3反义基因植物表达载体的构建及其对拟南芥的遗传转化

根据编码白菜(Brassica rapa L. ssp. chinensis,syn B. campestris ssp. chinensis)果胶甲酯酶的BcMF3 基因cDNA 序列内部第1 343～1 797个碱基之间序列设计引物,从白菜花蕾cDNA中PCR扩增出455 bp的片段,把该片段作为反义基因连接至双元载体pBI12l上,得到了植物表达栽体pBI-B3,并用"三亲杂交"法导入农杆菌LBA4404菌株中,PCR扩增和酶切结果表明所构建的植物表达载体pBI-B3含有BcMF3 反义基因片断,并已导入了根癌农杆菌(Agrobacterinm tumefuciens)中;采用花序浸润法转化拟南芥(Arabidopsis thaliana)后,播种筛选浸润植株的种子获得了5 株卡那霉素抗性植株,PCR 扩增证明BcMF3反义片段成功整合到拟南芥基因组中;转基因拟南芥子代(T2)的抗性分离符合孟德尔分离比例,表明外源基因是单一位点插入.     

外源BR诱导小白菜对霜霉病抗性的研究

以小白菜为材料,采用叶面喷洒的方法施用不同质量浓度的油菜素内酯(BR),研究BR对小白菜霜霉病的抗性诱导效应。结果表明,0.01～0.15mg/L BR处理均能极显著降低小白菜霜霉病的病情指数,其中,0.10mg/L BR诱导处理的病情指数最低,为29.36,极显著低于其他处理,此时抗病效果为36.60%。另外,经0.10mg/L BR诱导处理后,小白菜的株高达8.26cm,单株鲜质量达5.940g,单株干质量达0.780g,均高于其他处理和对照。研究还发现,BR处理后的第5天是诱导小白菜对霜霉病抗性效果最佳时间。     

ChIFN-α基因在烟草中的表达及转基因烟草对TMV的抗性

动物α干扰素具有高效广谱的抗病毒作用,通过农杆菌介导法将35S驱动的干扰素基因ChIFN-α转化烟草,Southern杂交和Western杂交进行目的基因的转化、表达检测,重组蛋白的数量通过ELISA测定,对获得的转基因烟草植株进行TMV接种实验,结果表明ChIFN-α基因的转化赋予了转基因烟草对TMV的抗性,进一步的荧光定量PCR差异表达检测结果表明,该抗性可能与转基因烟草体内防卫基因PR-la、抗病N基因和信号转导MAPK基因受到上调表达有关。     

农杆菌介导的细菌阿特拉津氯水解酶基因对水稻的遗传转化

 研究构建了植物表达载体p1301-atzA,使来源于节杆菌(Arthrobacter sp.)AD1菌株的阿特拉津氯水解酶基因atzA受控于CaMV35s启动子下表达。用农杆菌介导法将植物表达载体p1301-atzA导入粳型保持系津稻107中,经潮霉素抗性筛选,得到可育的再生植株。转基因植株总DNA经PCR和Southern检测表明atzA基因已整合到水稻的基因组中。对转基因植株进行除草剂阿特拉津抗性检测,在喷施浓度为0.133％的阿特拉津溶液后,对照植株和敏感植株死亡,而转基因植株表现出对阿特拉津的抗性,