抗芜菁花叶病毒转基因甘蓝型油菜的研究

以子叶柄为材料,建立了甘蓝型油菜（ＢｒａｓｓｉｃａｎａｐｕｓＬ．）双低品种的再生体系。通过子叶柄与农杆菌（ＡｇｒｏｂａｃｔｅｒｉｕｍｔｕｍｅｆａｃｉｅｎｓＬＢＡ４４０４）共培养,将表达载体ｐＢＴｕ中芜菁花叶病毒外壳蛋白（ＴｕＭＶ－ＣＰ）基因以整合方式导入甘蓝型油菜,然后用卡那霉素进行筛选,获得了油菜再生植株。经ＰＣＲ特异性扩增、点杂交和Ｓｏｕｔｈｅｒｎ印迹分析,证明再生植株基因组ＤＮＡ中整合了ＴｕＭＶ－ＣＰ基因。攻毒实验表明,有ＴｕＭＶ－ＣＰ基因插入的工程油菜对ＴｕＭＶ均有不同程度的抗性。     

用单克隆抗体作芜菁花叶病毒不同分离物外壳蛋白抗原结构的比较研究

用芜菁花叶病毒辽宁分离物（ＴｕＭＶ－ＬＮ）,山东分离物（ＴｕＭＶ－ＳＤ）和榨菜分离物（ＴｕＭＶ－ＺＣ）作抗原,分别免疫ＢＡＬＢ／ｃ小鼠,经脾细胞与ＳＰ２／Ｏ－Ａｇ１４骨髓细胞融合,共获得７个单克隆抗体分泌细胞株,为研究３个分离物的抗原差异,用胰蛋白酶消化ＴｕＭＶ的外壳蛋白（ＣＰ）。分别形成４、２和１条降解带,经ＳＤＳ－１５％ＰＡＧＥ后,转移至硝酸纤维薄膜上,用３个分离物的抗血清和７种单隆抗体分别做     

芸苔属蔬菜小孢子胚状体再生成苗及倍性鉴定

研究影响大白菜、甘蓝和红菜薹小孢子胚状体再生成苗的几个生理因素的结果表明,在1．0％～1．2％的琼脂中胚状体再生成苗率显著高于0．8％琼脂的。4℃处理10d可显著提高大白菜和甘蓝胚状体再生成苗率。大白菜和红菜薹胚状体再生成苗的最适胚龄为20—29d,甘蓝则为30—35d。培养基B,和MS对再生成苗率影响不大。检测3种芸苔属蔬菜小孢子再生植株的倍性结果表明,大白菜和红菜薹小孢子植株自然加倍率较高,均超过70％;甘蓝较低,仅为30％左右。同一物种的不同品种间胚状体再生成苗所需的条件和加倍效率基本一致。     

水稻游离小孢子培养最新研究进展

水稻小孢子培养技术不但可用来生产单倍体植株和加倍单倍体植株,而且可望成为转基因的理想受体系统。目前转基因技术、分子杂交技术与小孢子培育技术的有机结合已成为加快水稻育种速度的有效途径。本文从水稻小孢子分离纯化、影响愈伤组织或胚状体发生的因素以及植株再生三个方面综述了水稻游离小孢子培养的最新研究进展。最后就水稻小孢子培育技术急需解决的问题进行了讨论,并对小孢子培育技术发展前景进行了展望。     

马铃薯X病毒外壳蛋白基因在转基因烟草植株中的表达及抗病

通过根癌农杆菌介导的叶盘法,将马铃薯Ｘ病毒外壳蛋白基因导入烟草细胞并获得大量再生的转基因烟草植株。经胭脂碱检测、酶联免疫分析和Ｗｅｓｔｅｒｎ ｂｌｏｔ分析,证明已获得了具有马铃薯Ｘ病毒外壳蛋白基因表达的转基因烟草。用２μｇ／ｍｌ的ＰＶＸ磨擦接种烟草,８天后进行观察,发现对照植株开始发病,而转基因烟草植株在２０后才开始发病,有的转基因烟草植株在整个生长期中都不得病。对ＰＶＸＣＰ基因表达量较高的４株植     

马铃薯Y病毒组病毒高产量提取方法的建立

本文报道了高产量提取芜菁花叶病毒（ＴｕＭＶ）、莴苣花叶病毒（ＬＭＶ）、芋花叶病毒（ＤＭＶ）和大豆花叶病毒（ＳＭＶ）的提取方法。本方法通过使用高盐浓度的磷酸盐缓冲液以及在缓冲液中加入氯化镁和脲,并用ＴｒｉｔｏｎＸ－１００作为澄清剂,替代常规使用的氯仿和正丁醇,成功的提取到了大量病毒粒子,上述四种病毒提取的得率分别是ＴｕＭＶ为１７３．３ｍｇ／ｋｇ病叶,ＬＭＶ为９６ｍｇ／ｋｇ病叶,ＳＭＶ为１９９．２ｍｇ／ｋｇ病叶,ＤＭＶ为１７６．６ｍｇ／ｋｇ病叶。     

MDMV CP基因的克隆及其转基因玉米的研究

用RT-PCR方法分离了玉米矮花叶病毒外壳蛋白基因(MDMV CP),并且利用基因枪法将该基因导入玉米优良自交系18-599红、18-599白幼胚诱导的愈伤组织中。转化的愈伤组织在Bialaphos浓度(PPT)为8mg／L、10mg/L、5mg／L的筛选压下经过3次抗性筛选后,分别再生出可育植株12株和6株。PCR和Southem检测结果说明CP基因已整合到玉米自交系基因组中。对T1代转基因植株进行病毒人工接种试验,结果表明对照植株全部表现为感染玉米矮花叶病的典型症状,而转基因植株后代呈现不同程度的抗性。     

辣椒游离小孢子细胞团培养的胚状体形成

从预培养15天后的花药中机械游离小孢子及其细胞团,经28℃液体悬浮暗培养．30天后,获得了自球形期胚到子叶期胚发育程度不等的各类胚状体。从12个花药中可以形成高达22个胚状体,且子叶期胚的比例约为23％。显微镜检表明,这些胚状体来自游离的小孢子细胞．经核的对称分裂形成多核细胞或者早期形成多细胞团,最后经细胞的分裂分化形成。胚状体体表具毛,活力有差异。在适当培养基上,具活力的鱼雷期及子叶期胚状体均能发育成正常植株。7℃、32℃、35℃8天的胁迫处理均能诱导小孢子胚状体发生。但花药培养中7℃、35℃处理下的出胚率较32℃下高,而游离小孢子细胞团培养中以35℃、32℃下较好。7℃处理下获得的胚状体数很少．对产生这种现象的原因进行了探讨。出胚率在基因型间,不同胁迫处理温度间表现明显差异。而在温度处理的不同天数间差异不明显。流式细胞仪对再生株真叶的DNA含量分析表明．获得的再生株中具有单倍体、双单倍体以及单倍一双倍嵌合体植株。本结果为进一步开展辣椒雄性生殖途径的胚状体发育研究。提高辣椒成熟胚状体的频率提供了实验体系。     

羽衣甘蓝的小孢子胚诱导和植株再生

以羽衣甘蓝10个品种的游离小孢子培养,研究其胚状体及其再生植株诱导方法的结果表明,琼脂糖和活性炭对诱导胚状体发生及发育有促进作用;改良MS培养基中添加0.01%的活性炭可促进植株再生;确定1/2MS NAA 0.1 mg·L-1是优化生根的培养基;小孢子再生植株成活率可达74.6%.     

根癌农杆菌介导天花粉蛋白基因TCS转化茎瘤芥的研究

以茎瘤芥(Brassica junceavar.tumidaTsen et Lee)的子叶为外植体,通过根癌农杆菌(Agrobacterium tumefaciens)的介导,将天花粉蛋白(Trichosanthin,TCS)基因导入到茎瘤芥中。对所获得的31株抗性植株进行PCR扩增,其中阳性植株为23株;Northern blot分析结果表明基因TCS在转基因植株中能够正常表达。转基因植株接种病毒试验结果表明,转基因TCS的植株对芜菁花叶病毒TuMV的侵染有一定的抑制作用。     

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.     

Determination of stoichiometry of radioiodination of proteins

A sensitive method for the detection of small quantities of hydrophobic antioxidant free radical scavengers such as butylatedhydroxytoluene (BHT) and butylatedhydroxyanisole (BHA) in aqueous samples is described. The procedure involves extraction of the hydrophobic free radical scavenger into an organic solvent phase, followed by the subsequent reaction of an aliquot of this extract with the stable cation radical tris(p-bromophenyl)amminium hexachloroantimonate (TBACA). In experiments with BHT and BHA, the loss of TBACA absorbance at 730 nm was found to be linearly proportional to the amount of antioxidant added, with quantities of BHT as small as 200 pmol being easily detectable. In aqueous suspensions of dimyristoylphosphatidylcholine vesicles, assays of the aqueous BHT concentration showed that BHT partitioned strongly into the membrane phase, achieving very high BHT/phospholipid ratios. For a given concentration of BHT, partitioning into the membrane phase was greater in large, multilamellar liposomes than in either small, single-walled vesicles or in purified rat brain synaptic vesicle membranes. Direct assay of BHT and BHA in phospholipid membranes, however, was complicated by a nonspecific interaction between TBACA and the phospholipid.