拟南芥花分生组织决定基因AGL24对花发育的影响

AGAMOUS-LIKE 24(AGL24)基因编码MADS蛋白,在植物花发育的不同时期发挥着重要的作用。综述了AGL24如何通过和其他花分生组织决定基因的相互作用来影响拟南芥花的发育,调节开花时间,这将有助于人们对开花基因调控网络有更进一步的认识,能够在生产上有效的调控开花时间,从而为植物育种提供借鉴。     

C类花器官特征基因AGAMOUS(AG)调控植物花分生组织维持与终止研究进展

花分生组织的维持与终止在植物花器官发生和世代交替起着至关重要的作用。成功的花分生组织决定能够确保植物正常的生殖发育和生命周期进程。诸多研究表明AGAMOUS(AG)基因作为花器官分化和开花决定的主效调节因子,能够协调花发育过程中多种细胞命运决定。然而,关于AG参与调控植物世代交替及花分生组织维持与终止的分子调控机制尚不清晰。综述了近年来AG基因参与调控植物花分生组织维持与终止的研究进展及现状,以期为深入研究植物花器官分化过程中干细胞的维持和终止,以及干细胞活动与其他发育过程之间的分子调控过程提供参考。     

植物AP1基因研究进展(综述)

AP1(APETALA1)基因属于植物花分生组织特征基因和花器官形态特征基因,在控制植物花分生组织特性与花器官的形成过程中起着重要的作用。本文综述了近年来植物AP1基因结构、功能、表达调节及其与物种进化关系研究的新进展,并对其在果树上的应用研究进行分析和展望。     

矮牵牛编码 F3'5'H的蓝色基因表达载体构建及转化

类黄酮3',5'羟基化酶(Flavonoid-3',5'hydroxylase,F3'5'H)是花色苷代谢途径中的一个关键酶,能使花色素合成趋向于形成蓝色的飞燕草色素,从而使花色向蓝紫色偏移.本研究从蓝紫色矮牵牛(Petunia hybrida)花瓣中克隆了编码F3'5,H的蓝色基因Hf1,并通过PCR技术获得百合花特异表达启动子(PchsA),将百合PchsA与Hf1基因融合,构建了百合花特异表达启动子调控的Hf1基因植物表达载体,通过农杆菌介导的叶盘法转化粉红色矮牵牛.抗性筛选和PCR检测鉴定转基因植株,结果表明,成功地获得了转基因阳性植株.     

矮牵牛编码F3′5′H的蓝色基因表达载体构建及转化

类黄酮3',5'羟基化酶(Flavonoid-3',5'hydroxylase,F3'5'H)是花色苷代谢途径中的一个关键酶,能使花色素合成趋向于形成蓝色的飞燕草色素,从而使花色向蓝紫色偏移.本研究从蓝紫色矮牵牛(Petunia hybrida)花瓣中克隆了编码F3'5,H的蓝色基因Hf1,并通过PCR技术获得百合花特异表达启动子(PchsA),将百合PchsA与Hf1基因融合,构建了百合花特异表达启动子调控的Hf1基因植物表达载体,通过农杆菌介导的叶盘法转化粉红色矮牵牛.抗性筛选和PCR检测鉴定转基因植株,结果表明,成功地获得了转基因阳性植株.     

调控花发育的同源异型基因

对形态发生突变体进行遗传学和分子生物学分析,是揭示发育的分子调控机制的最有效的途径。最近,世界上若干开创性的研究小组正致力于用这种分子遗传学手段研究植物花发育的调控机制,并取得了令人瞩目的进展。     

高等植物成花基因的研究

高等植物的成花可分为两个阶段：由茎顶端分生组织转变成花分生组织和花器官的形成。前者主要受成花计时基因的控制,而后一阶段主要由植物的同源（异型）框基因调控。本文综述了近年来对植物成花调控基因的研究,并着重对第一阶段成花基因的功能、它们间的相互作用和特点进行了总结。 Abstract:Plant flower can be divided into two phases——from stem apex meristem tissue into flower meristem tissue and floral apparatus.The flower time genes control the flower development and the homologous genes control flower apparatus identify.This paper summarizes recent studies on plant flower and emphasizes on the first phase flower control genes,theirs interaction and function,characteristic of the homologous genes.     

花发育调控基因的研究进展

花发育调控基因的研究进展聂亭,马诚（中国科学院发育生物学研究所．北京１０００８０）白书农白书农所在单位为中国科学院植物研究所花的发育是植物生长过程的一个重要阶段。九十年代初,随着植物分子生物学研究方法的逐步发展和模式植物的建立,在花发育调控基因方面的研究已经取得了一些结果,它们主要集中在拟南芥菜,金鱼草及单子叶的玉米等材料。本文特对这些工作做如下简扼的介绍。     

Studies on Petunia hybrida Transformed with Flower-meristem-identity Gene AP1

Three deletion mutants of tobacco mosaic virus (TMV) 54-kD putative replicase gene (54K) were obtained by PCR, and cloned into plant expression vector p208, then transformed into Nicotiana tabacum L. cv. SR1 by Agrobacterium tumefaciens (Smith et Townsend) Conn Ti plasmid-mediated transformation. All the transgenic plants with the N-terminal deletion mutant, the C-terminal deletion mutant and the only 261 nucleotides region from the central part of the 54K ORF showed significant resistance against TMV.     

Ectopic Expression of the Pttkn1 Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm

A novel knottedl-like homeobox (knox) gene, Pttknl (Populus tremula×tremuloides knotted1), isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on theabaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.     

NEC1, a novel gene, highly expressed in nectary tissue of Petunia hybrida

To study the molecular regulation of nectary development, we cloned NEC1, a gene predominantly expressed in the nectaries of Petunia hybrida, by using the differential display RT-PCR technique. The secondary structure of the putative NEC1 protein is reminiscent of a transmembrane protein, indicating that the protein is incorporated into the cell membrane or the cytoplast membrane. Immunolocalization revealed that NEC1 protein is present in the nectaries. Northern blot analyses showed that NEC1 is highly expressed in nectary tissue and weakly in the stamen. GUS expression driven by the NEC1 promoter revealed GUS activity in the outer nectary parenchyma cells, the upper part of the filament and the anther stomium. The same expression pattern was observed in Brassica napus. GUS expression was observed as blue spots on the surface of very young nectaries that do not secrete nectar and do accumulate starch. GUS expression was highest in open flowers in which active secretion of nectar and starch hydrolysis had taken place. Ectopic expression of NEC1 resulted in transgenic plants that displayed a phenotype with leaves having 3-4 times more phloem bundles in mid-veins than the wild-type Petunia. The possible role of NEC1 gene in sugar metabolism and nectar secretion is discussed.     

紫色大花矮牵牛组织培养与植株再生

矮牵牛叶片外植体在MS+6-BA 1.0mg/L+NAA 0.1mg/L培养基上培养3周后产生致密的浅绿色愈伤组织;转入芽分化培养基MS+6-BA 0.5mg/L+4-PU 0.5mg/L+NAA 0.1mg/L 1周后,从愈伤组织表面不断分化产生幼芽;待幼芽长至3cm时转接至生根培养基1/2MS+NAA 1.0 mg/L+GA₃0.5mg/L中生根,长成完整植株。     

不同基质对矮牵牛插穗离体生根的影响

用泥炭、珍珠岩和芦苇末混配的9种基质进行矮牵牛(Petunia hybrida Vilm.)离体生根实验研究.结果表明,在泥炭基质上矮牵牛插穗的生根状况较好,3个品种的平均生根率达94.4%,显著高于含苇末的各基质.在泥炭基质上扦插的各品种的主根长和根数基本都高于芦苇末基质.芦苇末基质电导率高达2.77mS·cm-1,不适宜作为扦插基质.基质电导率和插穗生根率的相关性分析表明,矮牵牛扦插基质的电导率应控制在1.5mS·cm-1以下.IAA处理表明,激素对矮牵牛插穗生根影响不明显,基质和水分管理是扦插成功与否的关键.     

Tumor Transformation of Petunia hybrida via Pollen Co-Cultured with Agrobacterium tumefaciens

Pollen preparations usually show a high nuclease activity. Therefore, to avoid DNA degradation, co-cultures of pollen and Agrobacterium tumefaciens were evaluated as a new tool in gene transfer experiments. As a model system, Petunia pollen was co-cultured with an A. tumefaciens wild strain. The co-cultured pollen was used for pollination of Petunia flowers. The seeds obtained were germinated and one cotyledon per seedling was removed and put stalk upwards on nutrient agar. In 80% of the cotyledons a callus developed from the cut surface of the stalks which was screened for tumor transformation on hormone-free medium. In repeated subculturing some calli maintained growth on hormone-free medium. Two of these calli were habituated. One callus, the best growing one, showed on Southern blot analysis a distinct hybridization signal at 3.2 kb when probed with Hind III fragment 22 DNA, covering two genes responsible for hormone free growth. This is the exact size that could be expected when plant material has been transformed with T-DNA. Another callus gave a hybridization signal at 2 kb which could only be explained with chromosomal rearrangement. In these two calli there was no co-transformation of the nos-gene: nopaline synthase activity could be detected from none of the calli, and none of the calli DNAs hybridized when probed with the nos-gene. Bacterial contamination could be excluded by probing the DNAs with virfragments.     

矮牵牛(Petunia hybrida)开花过程中的可溶性蛋白质分析

在进行矮牵牛(Petunia hybrida)光周期诱导开花的过程中,对叶子中的可溶性蛋白质进行了分析,其中有4条与开花有关的特异蛋白,分子量分别为49.45 kD(a)、35.45 kD(b)、17.98 kD(c)和11.74 kD(d).在不开放的花苞中不含有蛋白质a和d,只有这4种蛋白质全出现时,才能形成花苞并且开放.花开了以后,蛋白质c和d就消失.即使在开花的植株中,各组织中的蛋白质也是不同的.茎中完全不含有蛋白质c和d,叶子和花中的蛋白质组成也是不同的.     

矮牵牛叶片体细胞胚胎发生发育的组织学观察

以矮牵牛生根试管苗的叶片为外植体,在培养基MS NAA0.1mg/L 6-BA1.6mg/L上诱导体细胞胚胎直接发生。从接种后第一天开始观察叶片愈伤组织发生、发育的外部形态变化,从接种后第七天开始,每隔3天取变化明显的叶片组织块切片观察其胚状体的组织细胞学连续变化。组织切片观察表明,矮牵牛叶片体细胞胚胎发生类似于合子胚的发育过程;矮牵牛体细胞胚起源于叶肉细胞,胚性细胞与非胚性细胞染色明显不同,体细胞胚胎与周边其它组织有明显界线;体细胞胚胎的发育经历胚性细胞、多细胞原胚、球形胚、梨形胚、心形胚、鱼雷胚、类子叶胚等几个阶段。     

Ectopic Expression of the Pttknl Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm.

A novel knottedl-like homeobox （knox） gene, Pttknl （Populus tremulaxtremuloides knottedl）, isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.     

矮牵牛花药培养及植株再生研究

采用花粉发育双核期的矮牵牛花药,研究不同浓度植物生长调节剂配比及不同浓度蔗糖和麦芽糖对花药诱导率的影响。结果表明,采用6-BA和IBA组合诱导效果较好;NH+6-BA 1.5mg/L+IBA 1.5mg/L花药诱导率较高;麦芽糖诱导效果明显比蔗糖好。