利用改进的Cap-trapper法构建拟斯卑尔脱山羊草(Ae.speltoides Tausch)全长cDNA文库

Captrapper法是目前全长cDNA文库构建的重要方法之一。在引进、消化、吸收的基础上,通过设计引物,同位素检测,对末端转移反应条件控制等方面做了一些切实可行的改进,形成了一套简单易行的技术体系。利用改进的Captrapper方法,成功构建了小麦B基因组的可能供体种拟斯卑尔脱山羊草(Ae.speltoides)的全长cDNA文库。经综合评价,文库的全长比例达到89.6%,重组率为99%,库容量超过3.0×106cfu。     

红果人参叶中cDNA文库的构建

以四年生红果人参叶片为材料,提取叶中总RNA合成cDNA,连接到质粒载体pDNR-LIB上。采用电穿孔法将重组质粒转化到DH5α中。经文库质量鉴定表明:原始文库滴度为1.008×106pfu·mL-1,扩增后的文库滴度为2.968×109pfu·mL-1,重组率接近100%,插入片段大小在0.5~2kb之间,平均为0.85kb,表明已成功构建了红果人参叶中cDNA文库。     

盐生植物海马齿盐胁迫全长cDNA文库的构建与分析

为了研究盐生植物耐盐基因表达调控,本实验以海水浇灌的海马齿植株为供试材料,构建了盐胁迫下的全长cDNA文库。构建方法如下:采用改良的CTAB法提取总RNA,SMART法反转录合成cDNA,LD-PCR方法合成双链cDNA。LD-PCR产物经蛋白酶K消化和SfiⅠ酶切后,经CHROMA SPIN+TE-1000分离柱子除去小片段DNA后,回收0.5kb以上的片段,按照适当的比例连接λTripIEX2载体。连接产物利用MaxPlaxTMLambda Packaging Extracts进行体外包装,得到海马齿初级cDNA文库。初始文库的独立克隆数为2.4×106pfu,初级文库滴度大于4.80×106pfu/mL,重组率为93.75%,插入片段为0.5～5kb,扩增文库的滴度为1.21×109pfu/mL,所得文库质量较高。本研究表明该cDNA文库适合于盐生植物海马齿相关基因的克隆和分析。     

SMART技术构建栀子cDNA文库

目的:构建栀子叶片cDNA文库。方法:提取栀子叶片总RNA。利用SMART技术合成双链cDNA。双链cDNA经限制酶Sfil酶切后与pDNR-LIB质粒连接。利用电刺激转化法将重组质粒导入E.coli DH5α而获得文库。利用PCR法检测文库的重组率。结果:原始文库滴度为2.63×105cfu/ml。随机检测文库中的15个克隆,表明重组率约为86.7%。选择14个插入片段的长度在400bp以上的克隆进行测序和生物信息学分析,结果预测的全长基因占所检测序列的64.3%。结论:成功构建了栀子叶片的cDNA文库,为栀子基因的结构和功能的研究提供了基础。     

大乳头水螅RACE cDNA文库的构建

目的:为筛选和克隆大乳头水螅发育调控相关基因的全长cDNA,构建大乳头水螅RACE cDNA文库.方法:提取大乳头水螅总RNA后从其中分离mRNA,运用SMART技术构建RACE cDNA文库.为鉴定所构建文库的质量,根据GenBank中大乳头水螅actin基因cDNA序列设计5'RACE和3'RACE的引物及用于扩增actin基因编码区全长序列的引物.结果:琼脂糖凝胶电泳结果表明,RACE cDNA文库中全长cDNA的长度集中在500-2 000bp之间.5'RACE、3'RACE PCR及扩增actin基因编码区全长序列时均以本文构建的大乳头水螅RACE cDNA文库为模板,这3个PCR反应均能扩增出产物,产物大小与目标片段预计大小相似.PCR产物分别经T/A克隆及测序后证明为大乳头水螅actin基因cDNA的相应序列.结论:RACE cDNA文库的成功构建为通过RACE方法获得大乳头水螅功能基因cDNA全长序列奠定了基础.     

灰绿藜RNA提取方法及在cDNA文库构建中的应用

目的:为分离灰绿藜耐盐相关新基因,构建叶片cDNA文库,探索从盐生植物中提取高质量RNA的方法.方法:以灰绿藜叶片为材料,应用RNA Plant Reagent法(Tiangen)、Plant RNA purification Reagent法(Invitrogen)、UNIQ柱式总RNA试剂盒提取法(Sangon)、SDS-LiCl法、TRIZOL试剂法(Invitrogen)等进行总RNA的提取,并构建其全长cDNA文库和抑制消减文库.结果:RNAPlant-Reagent法、Plant RNA purification Reagent法和UNIQ柱式总RNA试剂盒提取法获得的RNA完整性均不好;SDS-LiCl法提取的RNA完整性好(28S条带亮度是18S的2倍、条带锐利清晰)、纯度高(A280/A260为1.89±0.03,A260/A230为2.23±0.02),适合用于直接反转录及构建全长cDNA文库,并获得成功;TRIZOL试剂法简单快捷,产率高(2724±82μg/g),完整性较好,可经mRNA纯化后用于抑制消减文库的构建并获得成功.结论:建立了用于构建高质量cDNA文库的灰绿藜RNA的制备方法.     

野生大豆种子cDNA文库的构建与分析

为了分离与鉴定野生大豆优良基因,以双高型优质野生大豆的近成熟种子为材料,采用裂解法提取了总RNA;以Oligo（dT）为引物,经SA—PMPS法分离出mRNA,反转录酶催化合成cDNA,并以cDNA第一链为模板在DNA聚合酶Ⅰ的作用下合成cDNA第二链,双链cDNA经加接头等步骤,成功构建了野生大豆cDNA文库。文库的重组率约为93．7％,PCR检测重组克隆的插入片段平均大于1000bp,测序片断大于500bp,表明构建的近成熟种子cDNA文库质量较高,为进一步进行EST测序和全长克隆打下了基础。     

Gateway技术构建菊芋块茎全长cDNA文库及EST测序分析

为丰富菊芋功能基因组学研究基础平台,以成熟期菊芋块茎为材料,将菊芋全长cDNA与Gateway供体载体pDONR222重组,构建了菊芋非剪切型全长cDNA文库。文库质量分析表明:未经扩增的原始文库库容量为5.76×10~6 CFU,插入片段大小主要为1～3000 bp,重组率为100%(24/24),达到了高质量文库的标准。利用该文库进行表达序列标签(expressed sequence tag, EST)测序,得到2639条高质量的EST序列,拼接后获得1895条非重复的唯一表达序列(unigene)。与NCBI的NR数据库同源比对分析表明,共有1533条unigene(80.9%)与已知基因有显著的同源性。GO分类结果显示:菊芋块茎表达基因在分子功能类群中,结合和催化活性所占比例最高。此cDNA文库将可用于菊芋功能基因组研究、新基因筛选、高通量EST测序以及菊芋cDNA芯片的制备等。     

甜菜夜蛾触角全长cDNA文库的构建与分析

目的:构建甜菜夜蛾触角全长cDNA文库。方法:利用TRIzol试剂提取甜菜夜蛾触角总RNA,以此为模板,通过SMAR-TScribeTM反转录酶反转录合成第一链cDNA,引物扩增获得双链cDNA,经Proteinase K消化、SfiⅠ酶切和CHROMA SPIN-400Column分级分离后,收集400～2 000 bp之间的片段重组于改造的pUC19载体并转化至大肠杆菌Escherichia coli DH5α,最终构建获得甜菜夜蛾触角全长cDNA文库。结果:对文库进行滴度测定和重组率分析,结果表明构建的cDNA初级文库滴度为1.6×107pfu/ml,重组率为94%,插入片段大小为0.5～3.0 kb,平均长度在1 kb以上,表明构建获得的文库是一个高质量的文库。结论:该文库的构建为今后克隆甜菜夜蛾嗅觉相关基因奠定了基础。     

米曲霉(Aspergillus oryzae) RIB40全长cDNA文库的构建

【目的】构建米曲霉RIB40的全长cDNA表达文库,为米曲霉功能基因的开发以及次生代谢产物合成途径相关基因的筛选与克隆奠定基础。【方法】采用RNAiso法从米曲霉RIB40菌体中提取总RNA。选用PolyATract mRNA Isolation System Ⅲ试剂盒分离纯化mRNA。以5μg mRNA为模板,按照ZAP-cDNA Synthesis Kit试剂盒说明书要求合成单、双链cDNA,使用CHROMA SPIN-400柱离心层析纯化后连接于Uni-ZAP XR表达载体上,体外包装后转染Escherichia coli XL1-Blue宿主菌。【结果】构建了米曲霉RIB40的全长cDNA文库,初级文库滴度约为2.96×106 CFU/mL,重组率约为97.8%,插入片段平均长度大于1.5 kb,达到一个高质量cDNA文库的要求。文库扩增后,滴度达到3.4×1010 CFU/mL。【结论】米曲霉RIB40全长cDNA表达文库的成功构建,将会对米曲霉基础生物学研究及相关基因的筛选与克隆奠定基础。     

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。