岩白菜ISSR-PCR反应体系的优化

目的:优化岩白菜ISSR-PCR反应体系,为利用ISSR标记进行岩白菜遗传多样性研究服务。方法:采用5因子4水平正交设计法优化岩白菜ISSR-PCR反应体系。结果:五个因子从大到小的影响力排序结果为:dNTPs>Mg2+>模板DNA>引物=Taq酶。岩白菜ISSR-PCR最佳反应体系为:总体积25μL,内含10×PCR缓冲液2.5μL、2.5 mmol.L-1Mg2+、2.0 U Taq酶、0.2 mmol.L-1dNTPs、0.48μmol.L-1ISSR引物、125 ng模板DNA。结论:研究获得的最佳反应体系具有标记位点清晰、反应系统稳定、检测多态性能力强、重复性好等特点,为利用ISSR标记技术研究岩白菜遗传多样性奠定了基础。     

毛薯ISSR-PCR反应体系的建立

本研究主要建立毛薯ISSR-PCR的最佳反应体系。研究采用改良CTAB法提取毛薯总基因组DNA,应用单因子实验法设定模板DNA,Mg2+浓度,dNTP浓度,Tap酶浓度以及退火温度的5个不同梯度,探讨单因素变化对毛薯ISSR-PCR扩增的影响。实验结果表明,毛薯ISSR-PCR最佳反应体系为:总体积20μL,模板DNA为50ng、Taq酶为0.8U、Mg2+浓度为2.0mmol/L、引物浓度为0.5μmol/L、dNTPs浓度为0.5mmol/L。     

芋ISSR-PCR扩增反应体系的建立

目的:获得清晰可靠、重复性较好的ISSR-PCR扩增反应体系,应用于芋种质资源进行遗传多样性的研究中.方法:以芋的幼叶提取基因组DNA为材料,采用正交试验设计L16(45),从模板DNA浓度、引物浓度、Mg2+浓度、dNTPs浓度及TaqDNA聚合酶的用量5因素4水平出发,构建芋最佳反应体系.结果:芋ISSR-PCR的最佳反应体系为:在25μl的反应体系中,40ng DNA模板、0.4μmol/L引物浓度、2.5 mmol/L Mg2+、0.2 mmol/L dNTPs、1 U Taq DNA聚合酶.结论:利用芋种质资源对最佳反应体系的验证,结果显示该反应体系具有扩增稳定性.     

海南龙血树DNA提取与ISSR反应体系的优化

目的:从海南龙血树叶片巾提取出高质量的总DNA,建立与优化海南龙血树ISSR的反应体系.方法:采用4种DNA提取方法,提取海南龙血树叶片中的总DNA,并对DNA进行紫外和电泳检测.采用改良CTAB法提取了基因组DNA模板,对海南龙血树ISSR-PCR反应体系中各个主要影响因子进行了优化和筛选.结果:改良CTAB法提取的DNA A260/A260在1.7～1.9之间,纯度高、杂质少、DNA完整性好.根据PCR产物的琼脂精凝胶检测结果,由试验得到的最佳反应体系为:60ng模板DNA,1.5mmol/L Mg2+,0.25mmol/L dNTPs,1.0μmol/L引物,1U Taq酶,总体积为20μl.结论:改良CTAB法可以从海南龙血树叶片中提取高质最DNA,该反应体系适用于应用ISSR标记开展海南龙血树DNA指纹、遗传多样性等研究.     

大帽藓科植物ISSR-PCR反应体系优化

[目的]建立大帽藓科ISSR-PCR实验最佳反应体系。[方法]提取大帽藓科的基因组DNA,利用5因素4水平的正交设计实验方法对大帽藓科植物ISSR-PCR反应体系进行最佳反应体系的筛选。[结果]大帽藓科植物ISSRPCR的最佳反应体系为(20μL):即20μL体系中,PCR Buffer 2. 0μL、Mg2+2. 25 mmol/L,d NTP 0. 2 mmol/L,引物0.65μmol/L,Taq DNA聚合酶0. 7 U,模板DNA 10 ng。5个因素对该反应体系的影响顺序为:Mg2+引物 d NTP Taq DNA聚合酶模板DNA。利用该体系,在UBC808等13种引物中进行验证,均能得到有效的扩增条带。[结论]通过对大帽藓科基因组DNA的提取及体系优化,获得了大帽藓科植物最佳反应体系,为后续应用ISSR技术鉴定大帽藓科种质资源以及遗传多样性研究奠定了基础。     

维吾尔药茶昆仑雪菊ISSR分子标记体系的建立

研究适用于昆仑雪菊的ISSR-PCR反应体系,建立ISSR分子标记技术评价昆仑雪菊生态多样性体系。采用改良CTAB法、CTAB区室法、改良CTAB区室法、试剂盒法提取昆仑雪菊的新鲜叶片、干花以及种子的DNA;以827为引物,研究浓度、循环数、退火温度对ISSR-PCR反应体系的影响,以不同实验材料检测其适宜性。结果表明,昆仑雪菊新鲜叶片、干花以及种子的DNA的最佳提取方法为改良CTAB区室法,ISSR-PCR反应体系的最适引物浓度为1.0μmol·L-1,退火温度为54.6℃,循环数为30。ISSR-PCR反应体系适用于评价昆仑雪菊的生物多样性。     

光裸星虫ISSR-PCR反应体系的单因素优化试验

以光裸星虫为试验材料,通过单因素方法对影响其ISSR-PCR扩增效果的因子(模板DNA、Mg2+、dNTPs、引物、TaqDNA聚合酶、甲酰胺和二甲基亚砜)浓度进行研究。确立适合光裸星虫ISSR-PCR的反应体系:25μL体积含1×PCR buff-er、模板DNA用量为10-50 ng、TaqDNA聚合酶为0.75-1.75 U、Mg2+浓度为1.5-2.5 mmol/L、dNTP浓度为0.20 mmol/L,引物浓度为0.8-1.2μmol/L,甲酰胺和二甲基亚砜的添加并不能优化光裸星虫ISSR-PCR反应结果。利用所建立的体系对广西北海群体的20个光裸星虫个体基因组DNA进行ISSR-PCR扫描,结果表明,优化后的体系均能扩增出清晰、多态性高的条带。     

多用途树种无患子ISSR-PCR体系建立与检测

无患子(Sapindus mukorossi)是我国长江以南地区传统的重要绿化树种,其果皮富含皂苷,种仁富含油脂,为新型木本油料树种之一。为了获得基于KOD FX高保真DNA聚合酶试剂盒的无患子ISSR-PCR的最佳反应体系,该文采用正交优化设计相结合的方法,研究了引物浓度、d NTPs浓度、KOD FX酶、模板DNA浓度和Mg2+浓度对无患子ISSR-PCR反应体系的影响,并在此基础上对退火温度进一步优化,最终确立了适合无患子的ISSR-PCR反应的最佳体系和程序,即20μL PCR反应体系中,引物0.5μmol·L-1、d NTPs 0.05 mmol·L-1、KOD FX酶0.06 U·μL-1、模板DNA浓度1.0 ng·μL-1和Mg2+1.0 mmol·L-1。当以UBC841为引物时,PCR扩增程序为94℃预变性2 min,98℃变性10 s,48.6℃退火30 s,68℃延伸90 s,35个循环,68℃延伸7 min,4℃保存。这一优化的ISSR-PCR反应体系的建立,为无患子种质资源的遗传多样性、亲缘关系及遗传结构研究、种质创新与分子辅助育种等奠定了良好的基础。     

广西野生桃金娘SRAP体系优化及建立北大核心CSCD

利用均匀设计方法优化了桃金娘SRAP反应体系。得出最佳反应体系,其总反应体积为25μL,包括2.5μL10×PCR buffer,1.0U Taq DNA聚合酶,20 ng模板DNA,0.2 mmol.L-1 dNTPs,0.3μmol.L-1引物,2.5 mmol.L-1Mg2+。采用优化的扩增体系,以Me1-Em11引物组合对8个参试种质进行SRAP扩增,扩增出的条带清晰、多态性好。所确立的体系稳定可靠,适于进行桃金娘的SRAP遗传分析。     

大苞萱草ISSR-PCR反应体系的建立与优化

分别采用正交设计和单因子试验两种方法对影响大苞萱草ISSR-PCR反应体系的4个因素(Taq酶,Mg2+,dNTP,引物)在3个水平上进行优化试验。正交设计选用L9(34)方案,采用直观分析法获得影响因素最佳反应水平。单因子试验分别研究各因素对ISSR-PCR反应的影响情况,找出最佳反应水平。两种方法所得影响因素最佳水平存在差异,通过综合比较与分析,最终建立了大苞萱草ISSR-PCR的最佳反应体系。在20μL的反应体系中:Taq酶1 U,Mg2+1.5 mmol/L,dNTP0.20 mmol/L,引物0.4μmol/L,1×PCR buffer,30 ng模板DNA。在此基础上筛选出10个扩增稳定、多态性丰富的ISSR引物,并通过梯度PCR试验,确定引物最佳退火温度。     

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.     

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.     

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.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

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.     

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。