马铃薯PGBSS—GUS融合基因在块茎中专一性表达的初步研究

从ＧＢＳＳ基因克隆上，酶切得到５上游区１．２ｋｂ的序列，与ＧＵＳ报告基基因融合，构建了ＰＧＢＳＳ１．２表达载体，通过农杆菌介导的方式，将ＰＧＢＳＳ１．２转和马铃薯品种Ｄｅｓｉｒｅｅ，卡那霉素筛选获得抗性再生植和微薯，利用ＰＣＲ特异性扩增和Ｓｏｕｔｈｅｒｎ Ｂｌｏｔｔｉｎｇ的方法证明了融合基因在马铃薯基因组中的整合，Ｘ－Ｇｌｕｅ活体染色表明，微薯切片具有高ＧＵＳ酶活性，而茎段中ＧＵＳ活性相对较低，初     

一个含有玉米器官专一性启动子的表达质粒的构建

报道了玉米醇溶蛋白基因启动子的亚克隆以及利用该启动子和ＧＵＳ基因来构建表达质粒ｐＨＺＰ－ＧＵＳ。经过部分降解和亚克隆,得到玉米醇溶蛋白基因启动子,将该启动子与含ＧＵＳ基因编码序列和ＮＯＳ终止子的ＢａｍＨ Ｉ片段连接,构成融合基因。将该融合基因克隆到含有ＨＰＴ筛选标记基因的质粒ｐＧＬ２中,得到表达质粒ｐＨＺＰ－ＧＵＳ。     

微弹射击将大麦黄矮病毒外壳蛋白基因转入小麦获可育植株

以小麦品种济南１７７、３８４、４７１的幼胚和济南１７７的胚性愈伤组织为材料，质粒为ｐＰＰＩ２［含大麦黄矮病毒外壳蛋白（ＣＰ）基因和ＧＵＳ（β－葡萄糖苷酸酶）基因］；ｐＰＰＩ５（含ＣＰ基因）＋ｐＥｍｕＧＮ（含ＧＵＳ基因），用高速基因枪轰击钨粉质粒进入幼胚和胚性愈伤组织细胞．ＧＵＳ基因的瞬间表达平均频率幼胚约为４２％，愈伤组织为１８．５％．转化处理后用ＰＣＲ扩增技术检测植株中ＣＰ基因是否存在并稳定遗传．检测结果表明，来源于幼胚的Ｔ０代转化频率为２～９％（１９９３～１９９４年），并获得Ｔ１、Ｔ２和Ｔ３代稳定表达的转化植株．用愈伤组织转化，其转化频率３月龄者为０．４％；２年龄者为零．潮霉素（Ｈｍ）用于对转化幼胚和愈伤组织的筛选，低浓度时不能抑制非转化细胞的生长，高浓度则使细胞受伤害，不能再生正常健壮的植株     

GUS基因对红豆草部分酶解小细胞团的转化

采用电击法，将大肠杆菌的ＧＵＳ基因（β－葡糖苷酸酶基因为报告基因）导入红豆草部分酶解小细胞团，利用ＧＵＳ基因产物与底物Ｘ－Ｇｌｕｃ反应的组织化学定位试验，检测到ＧＵＳ基因在受体组织中的表达。同时，对部分酶解的程度、不同电压条件下的转化效率以及两种质粒的不同启动子对ＧＵＳ基因表达的强度等进行了讨论。     

大肠杆菌基因启动子探针型载体的构建

利用ＰＣＲ技术将ｐＵＣ１８和ｐＢｌｕｅｓｃｒｉｐｔ中的多克隆位点区（ＭＣＳ）及旁侧序列分别进行扩增,然后将扩增产物插入到已除去ＬａｃＺα基因的ｐＵＣ１８中,获得三个中间载体ｐＳＵＧＶ１,ｐＳＧＶ２和ｐＳＵＧＶ３,最后将ｐＳＵＰＶ２中无表达活性的新霉素磷酸转移酶Ⅰ（ＮＰＴⅠ）基因分别插入到三个中间载体的ＭＣＳ中,构建成功大肠肝菌基因启动子探针型载体ｐＳＵＰＶ４,ｐＳＵＰＶ５和ｐＳＵＰＶ６．     

大麦黄矮病毒（BYDV）外壳蛋白基因在小麦原生质体中的稳定转化

实验采用ＰＥＧ介导法转化小麦，用ＧＵＳ基因作为标志，用荧光法测定Ａｃｔｌ－ＧＵＳ、Ｅｍｕ－ＧＵＳ、３５Ｓ－ＧＵＳ三种质粒转化小麦细胞后的瞬间表达强度，以比较Ａｃｔｌ、Ｅｍｕ、３５Ｓ三种启动子在小表中的表达强度．结果表明，Ａｃｔｌ和Ｅｍｕ的强度大致相等，均比３５Ｓ强．采用Ｅｍｕ为启动子带ＢＹＤＶＣＰ基因的质粒和经改造过的Ａｃｔ１为启动子带有抗潮霉素选择标记基因的质粒共转化小麦“济南１７７”的原生质体．转化６ｄ后，用潮霉素进行筛选，最后得到两块抗潮霉素的愈伤组织，转化后４个月，经ＰＣＲ检测，证明ＣＰ基因已整合进一块愈伤组织的细胞基因组中．     

早熟禾的组织培养和基因枪介导的基因转化体系的初步建立

分析了不同质量浓度的２,４－二硝基苯酚对早熟禾愈伤组织诱导和愈伤组织分化成苗的影响,３ｍｇ／Ｌ和０．１ｍｇ／Ｌ２,４－Ｄ分别是本试验所用早熟禾基因型诱导形成愈伤组织和愈伤组织分化成勒的最适度量浓度。利用基因针ＧＵＳ基因的ｐＧＡ４７０和ｐＡｃｔ１－Ｄ质粒导入愈伤组织,通过组织染色法检测到Ｇｕｓ基因的瞬时表达。     

启动子对外源基因在转基因植物中表达的影响

将来自ｐＢＩ１２１质粒的ＣａＭＶ３５Ｓ启动子片段插入到ｐＢＩ１２１的ＣａＭＶ３５Ｓ启动子与ＧＵＳ基因之间，构建了串联的ＣａＭＶ３５Ｓ启动子载体ｐＬＢ３８．通过三亲交配，将ｐＢＩ１２１及ｐＬＢ３８分别转移到含ｐＧｖ３８５０的农杆菌中，成为适合本研究的双元载体。以叶圆盘转化法将外源基因转入烟草，获得了２种转基因植株。经ＤＮＡ分子杂交、ＮＰＴⅡ点分析、ＧＵＳ荧光定性及定量分析，证明外源基因已整合进烟草基因组并获得表达。ｐＬＢ３８的ＧＵＳ表达量为ｎＢｌ１２１的３～４倍，这表明启动子数目的不同会直接影响其启动基因的表达水平。     

基因重组人Gamma-干扰素发酵和提取优化工艺的研究

对基因重组人Ｇａｍｍａ－干扰素（ｒＩＦＮ－γ）ＰＢＶ２２０ＤＨ５α工程菌株的发酵工艺进行了研究．结果表明,采用在２５０ｍＬ摇瓶中装液量为１５０ｍＬ,按照１∶４０的稀释比进行两次扩大培养,并在大肠杆菌生长最为活跃的对数生长期内进行诱导表达效果最好．收集菌体以后,将菌体进行冷冻和超声破碎,并在２．０ｍｏｌ／Ｌ脲中浸泡８ｈ～９ｈ以清洗杂蛋白,然后用７．０ｍｏｌ／Ｌ盐酸胍（Ｇｕ·ＨＣｌ）提取．在优化工艺条件下,ｒＩＦＮ－γ的收量为９．０×１０６ＩＵ／Ｌ～１２．８×１０６ＩＵ／Ｌ,总蛋白为７９．５ｍｇ／Ｌ～１２７．２ｍｇ／Ｌ,比活为５．６×１０５ＩＵ／ｍｇ～８．０×１０５ＩＵ／ｍｇ,ＳＤＳ－ＰＡＧＥ电泳含量可达６０％～８０％,使ＰＢＶ２２０ＤＨ５α工程菌株获得了高效表达．     

GUS和HPT基因的基因枪法转化水稻

以水稻（丹粳－５号）愈伤组织为受体材料，采用基因枪法将含有ＧＵＳ和ＨＰＴ基因的ＣＭ２质粒导入水稻细胞．经过５０ｍｇ／Ｌ的潮霉素筛选，获得抗性愈伤组织，并在同样筛选压力下诱导分化成苗，获得抗性苗．共获得１７个抗性克隆．ＧＵＳ组织化学检测表明，有１２个克隆为ＧＵＳ阳性，ＧＵＳ和ＨＰＴ基因共表达率为７０％左右．Ｓｏｕｔｈｅｒｎ分子检测证明ＨＰＴ基因已整合到水稻基因组中．     

温度和光照对拟南芥VHA-c基因启动子活性的调节

转VHA-c2-GUS,VHA-c3-GUS和VHA-c5-GUS基因烟草在4℃和40℃温度胁迫以及25℃光/暗处理条件下叶片GUS表达水平表明,VHA-c具有光调控性,并可被逆境温度所调节.VHA-c2,VHA-c3和VHA-c5均可被4℃低温和光照促进表达.40℃高温可显著促进VHA-c3的表达,对VHA-c5有轻微的促进,而对VHA-c2则表现出轻微的抑制作用.     

Expression pattern of GASA,downstream genes of DELLA,in Arabidopsis

Separation and functional research of related components involved in gibberellins （GAs） signaling are important to clarify the mechanism of GA functioning. Research on the downstream components of DELLA, the key factor of the GA signaling pathway, is limited at present. GASA （GA-Stimulated in Arabidopsis） family contains 15 genes usually regulated by GA in Arabidopsis thaliana. All GASA proteins have a cleavable signal peptide in N terminus and a conserved GASA domain including 12 cysteines in C terminus. RT-PCR analysis revealed that the expression of GASA4 and GASA6 were down-regulated, but GASA 1 and GASA9 were up-regulated in the DELLA mutants, gai-t6 and rga-24, as well as the double mutant, consisting with the results that GASA4 and GASA6 were induced, but GASA1 and GASA9 were inhibited by exogenous GA3. In addition, the expression patterns of other GASA genes were regulated by GA and ABA, separately or cooperatively. Most of GASA genes were expressed in roots, stems, leaves, flowers and developing siliques. GUS gene driven by the promoters of GASA6, GASA7, GASA8, GASA9, GASAIO, GASA11 and GASA12were used as reporters and it was found that all GASA genes expressed in the growing and differentiating organs and abscission zones, suggesting the role of these genes in cell growth and differentiation. This study provided an important basis for functional study of the GASA gene family in the GA and ABA signaling pathway.     

水稻Rho家族OsRac2启动子的转基因功能鉴定

采用PCR扩增的方法,构建了OsRac2基因转录起始位点上游1.7 kb的启动子5′缺失植物表达载体,转化烟草并筛选阳性转基因植株.以多种激素处理转基因烟草,通过组织化学分析和GUS荧光活性的检测,证实Os-Rac2启动子上存在着一些激素应答元件,该基因的表达可能受茉莉酸的正调控,脱落酸等激素的负调控.     

基因枪法转化香蕉薄片外植体的参数优化

采用果用香蕉（Ｍｕｓａ ｓｐｐ．）的薄片外植体作为转化受体,通过对ＧＵＳ基因瞬间表达的研究,找出了较适合的轰击条件和外植体培养条件,研究表明,高渗处理对转化的影响较大,轰击前后对体外植体进行高渗处理的瞬间表达率（１４．１１％）是对照（３．６８％）的３．８６倍。预防培养外植体转化的瞬间表达率（１７．５％－４２．１１％）普遍高于没有预培养的外植体（１２．２０％）,并以预培养６ｄ为好。最适压力和射程分别     

Functional analysis of cis-acting sequences regulating root-specific expression in transgenic tobacco

Two different length fragments, RSF1 and RSF2 which contained the cis-acting sequences of root-spe- cific gene TobRB7, were isolated from tobacco genome. The abilities of these fragments to direct root-specific expression were studied by fusing them to the β-glucuronidase (GUS) report gene with different directions. After the recombined vectors were transformed into tobacco, the expression pattern was performed by histochemical staining and the quantitative analysis of GUS activity. The data suggested that the cis-acting element of TobRB7 gene direct GUS expression not only as root-specific but also as bidirectional. In our studies, the short fragment, RSF2, performed stronger activity than RSF1 with any direction. The stronger activity of GUS expression was determined by reverse inserting of RSF1 or RSF2 than positive inserting.     

Functional analysis of cis-acting sequences regulating root-specific expression in transgenic tobacco

Two different length fragments, RSF1 and RSF2 which contained the cis-acting sequences of root-specific gene TobRB7, were isolated from tobacco genome. The abilities of these fragments to direct root-specific expression were studied by fusing them to the β-glucuronidase (GUS) report gene with different directions. After the recombined vectors were transformed into tobacco, the expression pattern was performed by histochemical staining and the quantitative analysis of GUS activity. The data suggested that the cis-acting element of TobRB7 gene direct GUS expression not only as root-specific but also as bidirectional. In our studies, the short fragment, RSF2, performed stronger activity than RSF1 with any direction. The stronger activity of GUS expression was determined by reverse inserting of RSF1 or RSF2 than positive inserting.     

Identification of a bi-directional promoter from Tomato yellow leaf curl China virus

A bi-directional promoter of Tomato yellow leaf curl China virus (TYLCCNV) was obtained with the total DNA from TYLCCNV isolate Y10 infected tobacco leaves as a template. Plant expression vectors were constructed by fusing the amplified DNA fragment with the gus gene and nopaline terminator in different orientations. The vectors containing promoter fragments were transferred into leaf cells and plant stems of Nicotiana benthamiana by Agrobacterium-mediated method. Transient expression results showed that both the complementary and virion-sense promoters could drive the gus gene to express, and the GUS activity of the complementary-sense promoter was stronger than that of the virion-sense. Co-expression of the vector containing βC1 gene of TYLCCNV DNAβ with the vector containing a bi-directional promoter revealed that the βC1 protein has no impact on expression of either the virion- or the complementary-sense promoter.     

Introducing antisense <Emphasis Type="Italic">waxy</Emphasis> gene into rice seeds reduces grain amylose contents using a safe transgenic technique

Rice (Oryza sativa L.) eating quality is one of themost important traits. Amylose content (AC) in rice en-dosperm is a major index affecting rice eating quality[1,2].It has a negative correlation with gel consistency of rice[3].Based on amylose content, r…     

具全期启动子盒的杆状病毒高效表达载体的组建与应用

通过ＰＣＲ扩增，得到苜蓿丫纹夜蛾核型多角体病毒（ＡｕｔｏｇｒａｐｈａｃａｌｉｆｏｒｎｉｃａＮｕｃｌｅａｒＰｏｌｙｈｅｄｒｏｓｉｓＶｉｒｕｓ，ＡｃＮＰＶ）具早晚期启动子元件的ｐ３５基因启动子，将其插入到杆状病毒转移载体质粒ｐＳＸＩＶＶＩ＋Ｘ３多克隆位点上游，使之与ｐＳＸＩＶＶＩ＋Ｘ３质粒中的人工合成后期启动子（ＰＳｙｎ）、多角体ＸＩＶ启动子（ＰＸＩＶ）串联构成早期、晚期、极晚期能持续启动外源基因表达的转移载体质粒ｐＳＸ３５．将ｐＳＸ３５用于组建含ＨＢｓＡｇ基因并形成多角体的重组ＴｎＮＰＶ，ＨＢ－ｓＡｇ基因的表达量显著提高，表达时间亦明显提前，从而实现了外源基因在杆状病毒表达系统的全期、高效表达．ｍＲＮＡ引物延伸试验结果显示，Ｐｐ３５在重组病毒中可产生２套转录本，分别于病毒感染的早期和晚期起始ＨＢｓＡｇ基因的表达．