应用PCR产物直接银染测序技术检测大肠癌p53基因点突变 Detection of p53 Point Mutation in Colorectal Carcinoma Using PCR-product DNA Silver Sequencing

应用PCR-SSCP结合PCR产物直接银染测序技术对24例大肠癌p53基因第5-7外显子进行点突变的研究。结果检出5例(26.7%)阳性,均为错义突变;其中3例为碱基GC到 AT的转换, 1例为GC到TA的颠换,另1例为AT到CG的颠换,后者尚未见报道。突变位点分布在p53基因第141、175、245、248和258位密码子,其中4例发生在CpG位点。本文对p53基因点突变谱的分析为大肠癌的病因学研究提供了科学依据, 并讨论了PCR产物直接银染测序技术的优越性。 Abstract:Mutations in exon 5~7 of p53 were screened in 24 cases of colorectal carcinoma by a combination of PCR-SSCP and PCR-product DNA silver sequencing.The results showed that all 5(26.7%) cases of point mutations detected were missense mutations,including 3 cases of GC to AT transitions,1 case of GC to TA transversion and another case of AT to CG transversion.The latter has not been reported before.The mutations occurred at codons 141,175,245,248 and 258 respectively,and 4 cases of these five mutations occurred at CpG dinucleotides.The analysis of p53 mutation spectra can provide clues to the etiology of colorectal carcinoma.The advantages of DNA silver sequencing are also discussed.     

Leber遗传性视神经病变家系的线粒体基因突变分析

为探讨Leber遗传性视神经病变（Leber′s hereditary optic neuropathy,LHON）家系线粒体DNA（mtDNA）常见致病原发突变的频谱,用聚合酶链反应（polymerase chain reaction,PCR）和单链构象多态性（single-stranded conformational polymorphism,SSCP）以及DNA测序的方法,对13个家系22位临床诊断为LHON的患者及其母系亲属21人的线粒体DNA进行检测,同时检测71例正常人作为对照。临床拟诊为LHON的13个家系中,11个家系存在mtDNA位点11778 G→A突变,另2个家系存在14484位点T→C突变。说明中国LHON病人存在线粒体DNA 11778或14484位点突变,其中14484位点突变在国内尚未见报道。 Abstract:The purpose of the study is to investigate the frequency of common pathogenic primary mitochondrial DNA mutations in pedigrees of Leber′s hereditary optic neuropathy (LHON).Mutations were determined by polymerase chain reaction (PCR),single-stranded conformational polymorphism (SSCP) and DNA sequencing.Twenty-two patients with suspicion of LHON and twenty-one their maternal relatives underwent molecular genetic evaluation.Seventy-one normal individuals underwent molecular genetic evaluation as control at the same time.Members from 13 families with suspicion of LHON,11 families had nucleotide position nt11778 G→A mutations.Another 2 families had nt14484 T→C mutations.It is concluded that the point mutations at nucleotides 11778 and 14484 are primary LHON mutations,but the point mutation of nt14484 is rare in Chinese.     

威宁绵羊和贵州半细毛羊STAT5b基因部分外显子SNP研究

为给贵州本地绵羊选种选育提供更好的科学依据,本试验利用威宁绵羊和贵州半细毛羊构建DNA池,设计4对引物扩增其STAT5b基因部分外显子及内含子序列。PCR产物经纯化后进行双向测序。利用DNAStar和BLAST分析确定多态性位点。利用生物信息学软件分析SNPs位点对STAT5b基因RNA二级结构、STAT5b蛋白二级及三级结构的影响。结果表明,在扩增的STAT5b基因中筛选到6个SNPs:exon5-G12A、exon8-G56A、exon8-C104T、intron2-A3164C、intron4-C1026T和intron5-T3323C,其中exon8-G56A为错义突变,导致编码的谷氨酸(Glu)变为赖氨酸(Lys);exon5-G12A和exon8-C104T多态位点均未改变氨基酸的编码,为同义突变;intron2-A3164C、intron4-C1026T和intron5-T3323C均在内含子区,不参与氨基酸编码。     

13例肝豆状核变性家系致病基因突变的检测和分析

为了研究Wilson病(wilson disease,WD)基因突变的类型和发生情况,探讨WD疾病的病因、临床特点,通过采用变性高效液相色谱(denaturing high performance liquid chromatography,DHPLC)方法结合DNA测序方法对13例无亲缘关系的患者及33住亲属进行A TP7B基因所有外显子及5'端非转录区突变检测.33例DNA标本确认11种基因突变,其中包括9种错义突变(p.R778L、p.R919G、p.T1178A、p.T977M、p.K1010Q、p.C490TERM、p.A874P、p.G943S、p.G943D),1种缺失突变(2790delCAT),1种剪切位点改变(c.1708-1G＞C (intron 4 +1 G＞C)).在13个家系中,发现4例R778L突变,2例2790delCAT,均为杂合型突变,涉及17个等位基因,本组检出率为70.8％(17/24).DHPLC-测序法是WD疾病基因突变筛查较为快捷、全面而且敏感的方法.WD基因突变存在热点区分别为3、8、12号外显子.2790delCAT、p.K1010Q、c.1708-1G＞C (intron 4+1 G＞C)是ATP7B基因新突变类型,p.S406A、p.V456L、p.V 1140A、p.R952K是中国人比较常见的多态类型.     

9个多态性STR基因座用于完全性葡萄胎的亲代来源鉴定

选取9个多态性STR基因座,应用多重PCR技术和聚丙烯酰胺凝胶电泳结合银染显色的方法,对33例病理学诊断为完全性葡萄胎的组织标本及夫妇双方外周血标本进行分子病理学分析研究,判定其DNA来源。结果表明,33例病理学上的完全性葡萄胎有27例DNA为单纯性父方来源,占81.8%(27/33),其中,纯合子完全性葡萄胎为22例,占66.7%(22/33),杂合子完全性葡萄胎5例,占15.1%(5/33);其余6例的DNA来自双亲,占18.2%(6/33)。葡萄胎的组织病理学诊断与其分子病理学诊断存在差异,提示9个多态性STR基因座分析法适用于鉴定葡萄胎DNA来源,具有准确可靠、快速、简便等优点,为进一步研究其恶变趋势提供可靠线索。
Abstract: To explore the genetic origin of hydatidiform mole (CHM), 33 cases of CHM were collected mainly from Harbin Red Cross Central hospital from 1998.6 to 2001.5 and studied by multiplex–PCR, products were separated using denaturing polyacrylamide gel and were detected by silver stain for 9 different STR loci analysis. Among 33 samples of CHM, DNA from only paternal origin was found in 27 cases (81.8%, 27/33), and from both parents in 6 cases (18.2%, 6/33); and in the former, the homozygous CHM and the heterozygous CHM were 22 cases (66.7%, 22/33) and 5 cases (15.1%, 5/33), respectively. There was difference between analysis of microsatellite DNA polymorphism and pathological diagnosis in hydatidiform moles’ classification. The results suggest that the analysis of 9 polymorphic STR loci is suitable for genetic original identification of hydatidiform moles.     

家兔UCP2基因多态性的筛选和生物信息学研究

本文研究兔的UCP2基因的多态性,为地方兔种的选种和选育提供一定的依据。分别以比利时兔、加利福尼亚兔和新西兰兔构建其DNA池,设计6对引物扩增3个兔种UCP2基因的外显子序列和部分内含子序列,用PCR产物直接进行双向测序快速的筛选出兔的UCP2的多态位点。结果表明:在兔UCP2基因中筛选到8个多态性位点:intron2-G2217T、exon3-A63C、exon3-G169A、intron5-C61A、exon6-C11G、intron6-C7T、intron6-C46T、intron6-C73A,其中exon3-A63C和exon3-G169A位于第3外显子上,且exon3-A63C为错义突变,导致编码的酪氨酸(Tyr)变为丝氨酸(Ser)。exon6-C11G在第6外显子上,其余的多态位点都在内含子中,除了intron6-C7T外,其余的多态位点在三种兔种中都有。结论:通过生物信息学对兔UCP2基因的分析发现m RNA二级结构、二级结构和蛋白质的三级结构在突变前后都发生变化。     

Inter-chain disulfide bond improved protein trans-splicing increases plasma coagulation activity in C57BL/6 mice following portal vein FVIII gene delivery by dual vectors

Protein trans-splicing based dual-vector factor VIII(FVIII) gene delivery is adversely affected by less efficiency of protein splicing.We sought to increase the amount of spliced FVIII protein and plasma coagulation activity in dual-vector FVIII transgene in mice by means of strengthening the interaction of inteins,protein splicing elements,thereby facilitating protein trans-splicing.Dual-vector delivery of the FVIII gene in cultured cells showed that replacement of Met226 in the heavy chain and Asp1828 in the light chain with Cys residues could facilitate inter-chain disulfide linking and improve protein trans-splicing,increasing the levels of spliced FVIII protein.In this study,C57BL/6 mice were coadministered dual vectors of intein-fused human FVIII heavy chain and light chain with Cys mutations via portal vein injection into the liver.Forty-eight hours post-injection,plasma was collected and analyzed for FVIII antigen concentration and coagulation activity.These mice showed increased circulating FVIII heavy chain polypeptide(442±151 ng mL-1 vs.305±103 ng mL-1) and coagulation activity(1.46±0.37 IU mL-1 vs.0.85±0.23 IU mL-1) compared with control mice co-administered dual vectors expressing the heavy and light chains of wild-type FVIII.Moreover,coagulation activity was similar to that of mice receiving a single vector expressing FVIII(1.79±0.59 IU mL-1).These findings indicate that improving protein trans-splicing by inter-chain disulfide bonding is a promising approach for increasing the efficacy of dual-vector based FVIII gene transfer.     

Analysis of genotypes and phenotypes in Chinese children with tuberous sclerosis complex

Tuberous sclerosis complex(TSC) is a neurocutaneous syndrome with serious clinical presentations, an autosomal dominant genetic disorder involving multiple organs and systems. We retrospectively investigated the clinical manifestations and genotypes of 20 Chinese children with TSC to enable informed diagnostic and surveillance recommendations in China. A retrospective analysis of clinical manifestations in 20 children(7.00±5.30 years old) with TSC was conducted. A genetic testing of the genes TSC1 and TSC2 was performed in 14 children.The earliest manifestations of TSC were skin lesions(80% of patients) and seizures(75%). Fourteen of the children presented with retinal hamartomas, and 2 of these underwent eye enucleation at other hospitals through misdiagnosis. On magnetic resonance imaging, 18 children exhibited subependymal nodules, and 16 ones showed cortical nodules. 5 cases of non-renal hamartomas, 5 cases of multiple renal cysts, and 5 cases of cardiac rhabdomyomas were observed.The genotyping of TSC1 and TSC2 in 14 children revealed 11 with mutations in TSC2, 2 with mutations in TSC1, and no mutations of either gene in one patient. Eight of these observed mutations are reported here in for the first time. The illness presentations of the TSC2-mutated patients were more severe than that of patients carrying TSC1 mutations.There were differences in the mutations of TSC genes in Chinese children from those reported in other countries. The described clinical characteristics and genotyping will help pediatric neurologists to understand, diagnosis, and treat TSC.     

应用PCR产物直接银染测序技术检测大肠癌p53基因点突变

应用PCR-SSCP结合PCR产物直接银染测序技术对24例大肠癌p53基因第5-7外显子进行点突变的研究。结果检出5例(26.7%)阳性,均为错义突变;其中3例为碱基GC到 AT的转换, 1例为GC到TA的颠换,另1例为AT到CG的颠换,后者尚未见报道。突变位点分布在p53基因第141、175、245、248和258位密码子,其中4例发生在CpG位点。本文对p53基因点突变谱的分析为大肠癌的病因学研究提供了科学依据, 并讨论了PCR产物直接银染测序技术的优越性。 Abstract:Mutations in exon 5~7 of p53 were screened in 24 cases of colorectal carcinoma by a combination of PCR-SSCP and PCR-product DNA silver sequencing.The results showed that all 5(26.7%) cases of point mutations detected were missense mutations,including 3 cases of GC to AT transitions,1 case of GC to TA transversion and another case of AT to CG transversion.The latter has not been reported before.The mutations occurred at codons 141,175,245,248 and 258 respectively,and 4 cases of these five mutations occurred at CpG dinucleotides.The analysis of p53 mutation spectra can provide clues to the etiology of colorectal carcinoma.The advantages of DNA silver sequencing are also discussed.     

百合查尔酮合成酶基因的克隆与分析

以西伯利亚百合为试材,通过半巢式PCR和RT-PCR技术分别克隆了查尔酮合成酶基因(CHS)的DNA和cDNA.生物信息学分析显示,CHS的DNA序列全长1 397 bp(登录号HM622754),包含2个外显子和1个内含子;cDNA序列编码区全长1 182 bp(登录号HQ161731),编码393个氨基酸,具有3个典型的CHS蛋白结构域:N-末端结构域(Lys3-Pro229)、C-末端结构域(Gln239-Pro389)和聚合酶Ⅲ结构域(Met1-Thr391);不同百合品种的CHS基因编码的氨基酸序列相似性高达98%,表明百合CHS基因在进化上呈现出十分保守的趋势;不同植物CHS基因序列的系统进化邻接树结果表明:百合与单子叶植物鸢尾及禾本科的水稻、大麦、玉米等亲缘关系更为接近.     

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.     

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.     

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.     

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。     

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.     

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.