RNAi载体导入黄瓜的遗传转化体系

以黄瓜(Cucumis sativus)子叶和子叶节为外植体,利用农杆菌(Agrobacterium tumefaciens)介导法建立黄瓜遗传转化体系并进行优化,将南方根结线虫(Meloidogyme incognita)寄生相关基因的RNA干扰载体导入黄瓜,通过潮霉素(Hyg)浓度梯度筛选得到99株潮霉素抗性植株。经PCR和Southern-blot检测,获得10株目的基因以单拷贝形式整合的转基因黄瓜,子叶和子叶节的Southern-blot阳性率分别为13.9%和6.9%。该研究建立并优化了RNA干扰载体导入黄瓜的高效遗传转化体系,成功获得了转基因黄瓜植株。     

RNAi载体导入黄瓜的遗传转化体系北大核心CSCD

以黄瓜(Cucumis sativus)子叶和子叶节为外植体,利用农杆菌(Agrobacterium tumefaciens)介导法建立黄瓜遗传转化体系并进行优化,将南方根结线虫(Meloidogyme incognita)寄生相关基因的RNA干扰载体导入黄瓜,通过潮霉素(Hyg)浓度梯度筛选得到99株潮霉素抗性植株。经PCR和Southern-blot检测,获得10株目的基因以单拷贝形式整合的转基因黄瓜,子叶和子叶节的Southern-blot阳性率分别为13.9%和6.9%。该研究建立并优化了RNA干扰载体导入黄瓜的高效遗传转化体系,成功获得了转基因黄瓜植株。     

暗培养对黄瓜子叶节再生频率及其相关酶活性和可溶性蛋白含量的影响

以黄瓜品种新泰密刺子叶节为材料,观测了暗培养1~5 d黄瓜子叶节植株再生频率及其诱导过程中POD、SOD活性和可溶性蛋白含量的变化,以探究暗培养条件下黄瓜子叶节POD、SOD活性、可溶性蛋白含量与再生频率间的关系.结果表明,暗培养不仅可以使黄瓜子叶节POD活性持续增长,还有助于其活性保持在较高水平,D4处理在培养的第6天POD值高达243 U?g-1FW,对应的再生频率为87.20%,而对照的最高峰值仅为187.7 U?g-1FW,再生频率只有36.60%;POD的变化体现了各处理生理状态的差异,且各处理暗培养结束时的POD活性水平和POD峰值分别与植株再生频率之间存在显著正相关性,相关系数分别达到了0.921和0.839;而SOD活性水平与再生频率间无显著相关性;可溶性蛋白含量虽然可以体现子叶节生理状态的变化,但无法反映各暗处理对再生频率的影响差别.可见,暗培养有助于提高诱导过程中黄瓜子叶节POD活性的增速,使其活性保持在较高水平,且以POD活性为指标可以反映暗培养处理的有效性.     

黄瓜子叶节高频再生体系建立及再生植株倍性观察

以‘农城3号’黄瓜子叶节为试材,研究不同苗龄、不同激素对黄瓜离体植株再生频率及再生不定芽的影响,并对再生植株进行了根尖染色体计数和叶片气孔保卫细胞叶绿体数目的鉴定。结果表明,(1)6-BA对黄瓜不定芽诱导起关键作用,IBA不利于黄瓜不定芽的诱导。(2)MS 2.0mg/L6-BA培养基是‘农城3号’黄瓜通过子叶节进行不定芽诱导再生植株的最佳培养基。(3)正常发育的无菌苗4~5d左右子叶不定芽再生频率较高,苗龄超过5d,不定芽再生频率明显下降。黄瓜子叶再生植株与实生苗的根尖染色体数目均为2n=14,再生植株与实生苗的气孔保卫细胞叶绿体数均分布在6~10的范围内,说明再生植株的倍性没有发生改变。     

黄瓜离体子叶节花芽和营养芽分化中CFL基因的表达

CFL基因是从黄瓜中克隆到的拟南芥LEAFY(LFY)同源基因.以离体黄瓜子叶培养物成花为实验体系,利用mRNA原位杂交技术对CFL基因在花芽和营养芽分化过程中的时空表达进行了分析.结果如下:在花芽分化过程中,CFL基因在花原基形成、花器官原基分化及各轮花器官形成之初强表达,在花器官形成以后表达减弱或不表达;在营养芽分化过程中,CFL基因在分生组织、叶原基和幼叶中有明显表达,在成熟组织中不表达.结果说明CFL基因的表达在黄瓜子叶节花芽和营养芽分化中原基的分化形成是必需的.结果提示CFL基因可能参与细胞分裂调控和启动、营养性分生组织向花分生组织转变等过程.     

重瓣紫蓝大岩桐组培苗的花同源异型现象(简报)

由于花同源异型突变体可作为研究花形态建成的分子遗传分析模式系统,近十几年来,人们对于花同源异型基冈的分离、鉴定及转化均产生了很大兴趣,并对花器官特征决定基因的功能提出了“ABC”控制模型J和“异时性”(heterchrrony)假说。我们在进行黄瓜子叶离体培养时,发现了离体培养黄瓜子叶直接成花现象,进而建立起黄瓜子叶离体培养直接成花及黄瓜去顶苗直接成花的实验系统。在栽培重瓣大岩桐组培苗的过程中,观察到六种花同源异型变异体,其表型难以简单地用“ABC”控制模型解释。通过统计还发现同源异型花的发生频率与节位有关。这一现象为进一步探讨花     

低营养条件下Paclobutrazol(PP333)对黄瓜去顶幼苗直接形成花芽的影响(简报)

植物开花机理是生物学中的一个基本问题,多年来人们进行过许多的研究,积累了大量的事实,然而对开花的机理仍然还不甚清楚。因而在利用原有实验系统的同时,有必要寻找更多简单,又便于分析的实验系统。Jullien等报告离体培养的大豆子叶节能直接产生花芽。我们在建立离体培养黄瓜子叶直接单独形成雄花或雌花的实验系统的过程中,发现黄瓜幼苗去除顶芽后在子叶节处也能直接形成花芽。这一现象有可能用于深入研究各营养器官和花启动间关系等问题,定将     

夏侧金盏花幼苗初生维管系统的解剖学研究

夏侧金盏花(Adonis estivalis L.)为毛莨科(Ranuncula-ceae)侧金盏花属(Adonis)植物。其幼苗可明显地分为上胚轴苗区、子叶节区和下胚轴根区。幼苗以子叶节区为中心,往上其子叶节区中部和上部为子叶节—茎过渡区;向下其下胚轴为子叶节—根过渡区。目前对毛莨科某些属幼苗初生维管系统的个体发育研究已有一些报道。但夏侧金盏花幼苗的子叶节—茎过渡区的转变与已报道的其他属均不同。主要表现为其子叶节区下部的中始式二原型双肩状单中柱,到达子叶节区中部,其后生木质部弦向发育成二唇形外韧维管束雏型,在中柱中央出现薄壁组织,进一步发育则形成髓;再往上,即子叶节区上部,便一分为多个内始式的外韧维管束雏型,直接形成上胚轴(茎)的真中柱。此研究为再一次验证子叶节区理论的正确性与进一步揭示被子植物初生维管系统的演化规律积累一份新资料。     

苦参碱对植物生长的刺激作用

应用植物激素生物试法测定了苦参碱（matrine)的某些植物生长调节活性,实验结果表明：苦参碱明显促进了离体黄瓜子叶鲜重和干重的增加;苦参碱降低了光下（5000lx,26℃）培养的离体黄瓜子叶的总叶绿素含量,但促进了离体黄瓜子叶的光合作用;苦参碱还显著促进了在暗中（25℃）培养的离体黄瓜子叶的生根作用和根的生长,这些现象说明苦参碱具有某些明显的植物生长刺激活性。     

钾对离体黄瓜子叶生根及根生长的促进作用（简报）

0.134～40.2mmol/L的KCI明显促进离体黄瓜子叶的生根、根长和根鲜重的增加。0.134～13.4mmol/L的KCl则抑制离体黄瓜子叶IAA氧化酶的活性。1.34mmol/L的高锰酸钾、酒石酸钾和邻苯二甲酸氢钾也促进离体黄瓜子叶的生根。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism