农杆菌介导GUS基因对多年生黑麦草转化的研究

通过检测愈伤组织中GUS基因的瞬间表达,研究农杆菌LBA4404/pCAMBIA1301介导多年生黑麦草的转化体系。通过对多年生黑麦草瞬间表达率的比较,确立了其遗传转化的最佳优化条件。研究发现,多年生黑麦草不同品种的转化率在25%~45%之间变化。多年生黑麦草遗传转化最佳优化条件是预培养10d的胚性愈伤组织、浓度为0.5~0.8OD的农杆菌菌液以及2d共培养时间。在共培养基中添加100μmol/L乙酰丁香酮能有效地提高植物瞬间表达率。两种侵染处理方法比较结果为滤纸滴加法比浸泡法更优。转化后对愈伤组织的干燥处理能抑制农杆菌过度繁殖,能改善愈伤状态,有利于提高转化率。     

影响农杆菌介导狗牙根遗传转化的因素

农杆菌LBA4404/pCAMBIA1301介导转化狗牙根的体系中,遗传转化的最佳优化条件是:胚性愈伤组织预培养10 d,农杆菌菌液浓度为OD600 0.5～0.8,共培养时间为2d.共培养基中添加100μmol·L-1乙酰丁香酮能有效地提高植物瞬时表达率.侵染处理方法中滤纸滴加法比浸泡法效果更好.黑暗条件下的瞬时表达率比12 h光照/12 h黑暗培养条件下的高.在最佳优化条件下狗牙根的GUS瞬时表达率达到36.36%.     

根癌农杆菌介导转化谷子的影响因素

利用GUS报告基因,建立了农杆菌介导的谷子(Setaria italica)遗传转化体系,并研究了多种影响因素对转化效率的影响,包括受体基因型、外植体类型、菌液浓度、培养基中乙酰丁香酮的浓度、侵染时间和共培养时间.确定了最优的转化条件为:以谷子幼穗诱导的愈伤组织为外植体,用低浓度的农杆菌菌液侵染30～40min,然后在含有0.1mmol/L乙酰丁香酮的LS培养基上共培养2d.     

农杆菌介导韭菜遗传转化相关因素的研究

以"汉中冬韭"韭菜品种为试验材料,用含有pCAMBIA3301质粒的根癌农杆菌菌株EHA105对影响韭菜遗传转化效率的多种因素进行研究。结果表明,诱导40 d的愈伤组织,GUS基因瞬时表达率达到93%,且最适宜于不定芽的分化;当乙酰丁香酮(AS)的浓度为100μmol/L时,愈伤的GUS表达率达到91%,植株再生率为7.9%,AS浓度增加时其值也不会增加;菌液OD600值为0.6侵染10 min时,与其他组合相比,外植体受伤程度小,GUS表达率及再生率最高;侵染后的愈伤共培养3 d后,农杆菌生长较少,GUS表达率为91.1%,而再生率达到7.2%,为最佳的共培养时间。通过试验得到韭菜遗传转化因素的最佳条件,为今后的遗传转化提供一些参考。     

大豆胚尖遗传转化体系优化及抗逆基因GmPK转化研究

采用GUS基因瞬时表达检测方法,通过正交试验以AS浓度、侵染菌液OD值、侵染时间、共培养时间和恢复培养时间5个因素在4个水平上进行分析,优化了农杆菌介导的大豆胚尖遗传转化体系,并在此基础上进行了抗逆基因GmPK的遗传转化。结果表明,采用共培养培养基中添加100μmol/L AS、侵染菌液OD600值0.9、侵染15h、共培养5d和恢复培养3d的转化条件最佳,GUS阳性率达74.59%,经PCR及RT-PCR进一步验证获得了转基因阳性植株。利用优化的最佳条件进行抗逆基因GmPK的转化,炼苗移栽成活的再生植株经PCR及PCR-Southern blotting验证,初步证明外源基因已经整合至大豆基因组,转化率为0.6%。     

适用于农杆菌侵染的玉米受体材料筛选

以培育的14个玉米新系为材料,对幼胚的Ⅱ型愈伤产率和愈伤再生率,以及幼胚和农杆菌共培养后幼胚的GUS瞬时表达率进行统计,据此判断不同自交系在组织培养中的潜力,及其是否为农杆菌的易侵染材料,最终试验选出了zpm5和zpm6两种既适合组织培养又对农杆菌敏感的基因型材料.在对成熟胚愈伤诱导率的统计中发现,成熟胚愈伤诱导率可以作为对幼胚愈伤诱导的预测手段,两者的愈伤诱导率呈正相关性.     

利用gfp报告基因优化农杆菌介导的水稻遗传转化

为提高农杆菌介导的水稻遗传转化效率,以晚粳97为转化材料,绿色荧光蛋白gfp基因为报告基因,采用正交试验L9(33)对影响农杆菌介导水稻的遗传转化因子进行优化。通过观察愈伤组织荧光表达情况,分析菌液浓度、共培养温度与共培养时间对农杆菌转化水稻的影响。结果表明,在OD660值为0.1、共培养21℃～23℃黑暗条件下,农杆菌与水稻愈伤共培养72 h,最有利于水稻的遗传转化,该条件下晚粳97愈伤组织荧光表达率达到70.9%。     

无核白葡萄愈伤组织瞬时转化体系的优化与应用

为了优化根癌农杆菌介导的葡萄愈伤组织瞬时转化体系,该研究以欧洲葡萄品种无核白(Vitis vinifera L.cv.Thompson Seedless)单芽茎段诱导的愈伤组织为材料,探讨重悬液pH、菌液浓度、真空渗透时间等主要因素对葡萄愈伤组织瞬时转化效率的影响。结果表明:(1)以激素组合分别为1.0mg/L BAP、1.0mg/L BAP+0.02mg/L NAA、2.0mg/L BAP+0.02mg/L NAA和4.0mg/L BAP+0.02mg/L NAA的系列培养基更适合无核白葡萄单芽茎段逐步诱导胚性愈伤组织。(2)葡萄愈伤组织瞬时转化体系中,重悬液pH 5.1,菌液浓度OD6001.0,真空渗透20min为转化效率最佳条件。(3)利用优化的瞬时转化体系瞬时转化无核白葡萄的不同组织,发现在不同器官中转化效率存在显著差异。其中以愈伤组织为受体的转化效率显著高于其他器官(65 231.99±3 339.29mU/g),而且愈伤组织的GUS组织化学染色最深,以叶片为受体的转化效率则最低。利用该体系转化质粒载体pCAMBIA0390∷GUS,瞬时表达产物经过GUS蛋白活性检测,结果表明该研究优化的葡萄愈伤组织瞬时转化体系有助于外源基因在葡萄愈伤组织内的表达,为后期通过转基因技术研究目标基因功能奠定了技术基础。     

农杆菌介导的玉米幼胚遗传转化体系的优化

本实验以玉米品种HiⅡ(PA*PB和PB*PA)的幼胚为材料,用根瘤农杆菌菌株EHA105和LBA4404对幼胚进行转化,将PTF102-GUS导入玉米中,借助GUS基因的瞬时表达率,对影响农杆菌介导玉米幼胚转化的部分因素进行优化。研究表明使用EHA105侵染HiⅡ幼胚;农杆菌浓度在OD550=0.3,侵染时间在10min;幼胚大小为1.0mm时,GUS染色瞬时表达率较高。     

根癌农杆菌介导的金发草遗传转化条件的优化

金发草(Pogonatherum paniceum)是一种多年生岩生草本植物,在生态恢复和景观建设中起着重要的作用。利用根癌农杆菌介导转化金发草胚性愈伤组织,通过GUS(β-葡萄糖苷酸酶)瞬时表达率研究菌液浓度、浸染时间、乙酰丁香酮(AS)浓度、葡萄糖浓度、共培养时间等因素对金发草转化的影响,并利用确定的最佳条件将GUS基因转入金发草,获得稳定表达转化植株。结果表明:菌液浓度(OD₆₀₀)为0.6,浸染时间为10min,添加20mg/L的乙酰丁香酮(AS)和10g/L的葡萄糖,共培养时间5d为最佳条件,GUS瞬时表达率最高。经过抗性筛选后最终获得阳性转基因植株频率为57%。再生植株经GUS染色和PCR检测证明,GUS基因已成功整合到金发草基因组中。此转化体系的建立为金发草的遗传改良及相关功能基因的研究奠定了基础。     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.     

（鱼句）亚科花（鱼骨）型鱼类骨骼系统的比较

对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。     

Time of detection of recessive genes: effects of system of mating and number of examined individuals

Summary Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, Siete Cerros 66 and Penjamo 62, as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of Penjamo 62 in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.