鳜鱼Mx蛋白全长cDNA的克隆和序列分析

Mx蛋白是一类由I型干扰素诱导表达的抗病毒蛋白。本研究以感染了鳜传染性脾肾坏死病毒(Infectious spleen and kidney necrosis virus,ISKNV)的鳜鱼为材料,提取肝脏总RNA,通过逆转录一聚合酶链式反应(RT-PCR)扩增出Mx蛋白基因的核心片段序列,再应用3’和5’快速扩增cDNA末端(RACE)方法PCR扩增Mx蛋白cDNA末端,最终获得鳜鱼Mx蛋白cDNA序列(GenBank登陆号：AY392097)。序列分析表明：鳜鱼Mx蛋白cDNA含有2391bp,其中编码区长1881bp,编码627个氨基酸残基,推测蛋白质分子量大小为7．15kDa。鳜鱼Mx蛋白具有脊椎动物Mx蛋白共有的结构特征：一个三联体GTP结合区域(GXXXSGKS/T、DXXG、T／NKXD)一个发动蛋白家族的典型结构特征序列(LPRGS／KGIVTR);以及C端高度保守的Leu拉链结构域。鳜鱼Mx蛋白全基因的获得为下一步研究鱼类Mx蛋白的抗病毒活性、作用机制,以及干扰素的检测奠定了基础。     

珊瑚藻R-藻红蛋白γ亚基基因的克隆

根据珊瑚藻(Corallina afficinalis L.)R-藻红蛋白γ亚基N末端部分氨基酸序列(P83592)设计简并引物,结合RACE方法,扩增获得g亚基的全长cDNA序列.结果表明,序列全长为2 308 bp(AY209894),5'非编码区长1 203bp,3'非编码区长145 bp,编码区长960 bp,编码320个氨基酸组成的前体,包含71个氨基酸构成的信号肽和249个氨基酸组成的成熟蛋白.成熟蛋白序列内部存在重复序列与前人的报道一致.珊瑚藻亚基cDNA序列不同克隆子的测序结果表明,g亚基cDNA序列存在不同的3'末端,说明该基因可能存在多个拷贝或存在转录后加工.此外,扩增获得g亚基DNA序列(AY308999),比较表明编码区内部没有内含子存在.本文是对珊瑚藻R-藻红蛋白g亚基基因序列的首次报道.     

干扰素诱导的鱼类Mx蛋白

Mx蛋白是干扰素诱导表达的蛋白家族中的成员,当机体和细胞受病毒感染或诱生剂处理时产生.Mx蛋白和其它干扰素诱导蛋白一起构成宿主细胞的抗病毒状态,以达到抗病毒的目的.研究表明,Mx蛋白具有抗病毒活性,还可能与其它基本生命活动如发育或分化,蛋白质分送和生长有关.在鱼类也发现多种Mx蛋白,具有Mx蛋白家族的共有特征在肽链末端有一个三联ATP/GTP结合区和发动蛋白家族的结构特征序列;在蛋白C端存在使Mx蛋白形成三聚体的Leu拉链结构以及定位信号.但是迄今没有发现鱼类Mx蛋白的抗病毒活性.文章最后对目前鱼类病毒病的防治及利用抗病毒基因进行鱼类基因工程抗病毒育种进行了探讨.     

缘管浒苔Rubisco酶大亚基基因编码序列rbcL克隆及分析

主要对缘管浒苔光合作用第一关键酶Rubisco大亚基基因(rbcL)进行了克隆分离.首先通过PCR特异性扩增叶绿体基因编码的缘管浒苔大亚基编码序列rbcL部分基因序列(1035 bp).依据基因步移原理,首次克隆得到缘管浒苔rbcL5'上游非翻译区序列(224 bp).据推测,rbcL 5'上游非翻译区序列存在类似原核生物的启动子元件-10区(TAAAAT)和-35区(TTGAAA).此外,依据3'-RACE(cDNA末端快速扩增技术)原理,克隆得到缘管浒苔rbcL3'末端cDNA序列(579 bp).     

鳜鱼CRP cDNA和斜带石斑鱼AAT cDNA的克隆与序列分析

采用RT-PCR及RACE法分别克隆得到鳜鱼(Siniperca chuatsi)C-反应蛋白(C-reactive protein,CRP)cDNA全序列和斜带石斑鱼(Epinephelus coioides)α1-抗胰蛋白酶(α1-antitrypsin,AAT)cDNA全序列.鳜鱼CRP基因cDNA全长为914 bp,其中5'非翻译区(5'-UTR)为49 bp,3'非翻译区(3'-UTR)为199 bp,开放阅读框(ORF)为666 bp,编码222个氨基酸.序列同源性分析发现,推测的鳜鱼CRP氨基酸序列与小鼠(Mus musculus)、人类(Homo sapiens)、大鼠(Rattus,norvegicus)、非洲蟾蜍(Xenopus tropicalis)和中国鲎(Tachypleus tridentatus)的CRP氨基酸同源性分别为33.2%、32.4%、31.5%、24.9%和22.4%.斜带石斑鱼肝脏ATT基因cDNA全序列长1 785 bp,其中,5'-UTR为13 bp,3'-UTR为530 bp,ORF为1 242 bp,编码414个氨基酸.序列同源性分析发现,推测的斜带石斑鱼AAT氨基酸序列与斑马鱼(Danio rerio)、非洲爪蟾(X.laevis)、楔齿蜥(Sphenodon punctatus)、大鼠、人类、狒狒(Papio papio)和小鼠的AAT氨基酸序列同源性分别为59.2%、40%、38.6%、38.5%、37.7%、37%和36%.鳜鱼CRP基因和斜带石斑鱼AAT基因cDNA全序列的获得为其疾病相关分子机理研究奠定了基础,对今后进一步进行种苗育苗的研发,并以此为依据提高其人工育苗仔鱼成活率有重要意义.     

马氏珠母贝Caspase-3基因克隆和组织表达分析

半胱氨酸蛋白酶3 (Caspase-3)作为细胞凋亡通路中重要的效应蛋白,在细胞凋亡过程中发挥着重要作用.为初步探究马氏珠母贝Caspase-3(PmCaspase-3)的生物学功能,本研究利用cDNA末端快速扩增(RACE)技术克隆获得PmCaspase-3基因cDNA的全长序列并对其序列特征进行分析;同时利用实时荧光定量PCR (RT-qPCR)方法分析了PmCaspase-3基因mRNA在马氏珠母贝不同组织和不同发育时期的表达差异.结果 显示,PmCaspase-3基因cDNA全长为2233 bp,其中5'端非编码区长度为80 bp,3'端非编码长度为31 bp,开放阅读框长度为2088 bp,共编码695个氨基酸;生物信息学分析显示,PmCaspase-3含有Caspase家族特有的CASc结构域和半胱氨酸蛋白酶家族p20、p10活性位点以及多种磷酸化位点,经进化分析以及多序列比对可知与其他物种Caspase-3蛋白同源性较高.RT-qPCR结果表明,PmCaspase-3在肝胰腺中的表达量最高,在闭壳肌中的表达量最低;在发育过程中D型幼虫期和眼点期的表达量较高.     

天祝白牦牛IGF-2基因的cDNA克隆

旨在克隆天祝白牦牛胰岛素样生长因子2(IGF-2)基因编码区全长cDNA序列,为研究该基因的生理功能奠定基础。运用cDNA末端快速扩增(RACE)技术获得天祝白牦牛IGF-2基因全长cDNA序列。扩增获得天祝白牦牛IGF-2基因全长cDNA序列为1 060 bp(GenBank登录号:KF682139),ORF长540 bp,编码179个氨基酸。其编码的氨基酸与已报道哺乳动物IGF-2氨基酸序列同源性在80%-92%之间。天祝白牦牛IGF-2基因的成功克隆为进一步研究该基因的功能奠定了基础。     

珊瑚藻R-藻红蛋白γ亚基基因的克隆(英文)

根据珊瑚藻(Corallina afficinalis L.)R-藻红蛋白γ亚基N末端部分氨基酸序列(P83592)设计简并引物,结合RACE方法,扩增获得g亚基的全长cDNA序列。结果表明,序列全长为2308 bp(AY209894),5′非编码区长1203bp,3′非编码区长145 bp,编码区长960 bp,编码320个氨基酸组成的前体,包含71个氨基酸构成的信号肽和249个氨基酸组成的成熟蛋白。成熟蛋白序列内部存在重复序列与前人的报道一致。珊瑚藻亚基cDNA序列不同克隆子的测序结果表明,g亚基cDNA序列存在不同的3′末端,说明该基因可能存在多个拷贝或存在转录后加工。此外,扩增获得g亚基DNA序列(AY308999),比较表明编码区内部没有内含子存在。本文是对珊瑚藻R-藻红蛋白g亚基基因序列的首次报道。     

紫杆柽柳与其它物种脂质转运蛋白基因编码蛋白的同源性比较

根据从柽柳cDNA文库克隆获得的脂质转运蛋白(LTP)的部分序列,用RACE技术克隆出其全长cDNA序列.基因的5'非翻译区96bp,3'非翻译区222bp,开放阅读框285bp,编码94个氨基酸,预计蛋白的分子量为9.9 kD,等电点为8.02.此基因有8个位置保守的Cys残基及26个氨基酸的信号肽,为典型的植物脂质转运蛋白基因.其基因序列数据库(GenBank)登录号为AY574218(基因)和AAS79106(蛋白).     

干扰素诱导的鱼类Mx蛋白

Mx蛋白是干扰素诱导表达的蛋白家族中的成员,当机体和细胞受病毒感染或诱生剂处理时产生。Mx蛋白和其它干扰素诱导蛋白一起构成宿主细胞的抗病毒状态,以达到抗病毒的目的。研究表明,Mx蛋白具有抗病毒活性,还可能与其它基本生命活动如发育或分化,蛋白质分送和生长有关。在鱼类也发现多种Mx蛋白,具有Mx蛋白家族的共有特征;在肽链末端有一个三联ATP／GTP结合区和发动蛋白家族的结构特征序列;在蛋白C端存在使Mx蛋白形成三聚体的Leu拉链结构以及定位信号。但是迄今没有发现鱼类Mx蛋白的抗病毒活性。文章最后对目前鱼类病毒病的防治及利用抗病毒基因进行鱼类基因工程抗病毒育种进行了探讨。     

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.     

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.     

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.     

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.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

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.