工程菌表达马铃薯钙调素(PCM 6)的抗体制备及鉴定

PCM6是马铃薯钙调素亚型中与其他植物钙调素在氨基酸序列上最为保守的一种，利用大肠杆菌表达系统，表达并纯化了这种蛋白，以纯化的重组马铃薯CaM(PCM6）蛋白为抗原，免疫新西兰兔，获得了高效价（1：16000）抗体，免疫印迹检测表明，制备的抗体与植物钙调素有特异性的免疫交叉反应。     

抗CPAα毒素单链抗体基因的克隆和表达及其生物学特性研究

应用RT—PCR技术 ,从分泌具有中和活性的抗A型产气荚膜梭菌 (CPA)α毒素单克隆抗体的杂交瘤细胞中 ,扩增出单链抗体 (ScFv)基因 ,并将其定向克隆于表达载体 pHOG2 1中 ,构建重组表达载体 pHOG 2E3,转化至大肠杆菌XL1 Blue中 ,筛选出表达菌株XL1 Blue(pHOG 2E3)。SDS PAGE分析结果表明 ,在 2 0℃用IPTG诱导培养时 ,表达的ScFv蛋白占菌体总蛋白的 2 5 %,ScFv蛋白主要以包涵体的形式存在 ,但在胞周质和培养上清中也能检测到ScFv蛋白 ,其中在胞周质中表达的ScFv蛋白占菌体可溶性蛋白的 4 %。生物学试验结果表明 ,ScFv基因表达产物不仅能够中和α毒素的磷酯酶C活性 ,而且对攻击致死剂量α毒素的小鼠产生良好的被动保护作用     

水蛭素基因的递归PCR合成和在大肠杆菌中的表达与分泌

水蛭素是凝血酶最强的特异抑制剂，可望成为预防和治疗各种血栓疾病的有效药物。根据医用水蛭头部水蛭素（ＨＶ－２）的氨基酸序列，通过递归ＰＣＲ，合成水蛭素基因，并重组到本实验室改建的大肠杆菌分泌型表达载体ｐＩＮ－＝ｏｍｐＡ－ＨＩ中，使水蛭素基因的编码序列直接位于大肠杆菌外膜蛋白Ａ信号肽序列的下游。转化大肠杆菌ＤＨ５α，筛选出重组体，经ＰＣＲ，限制酶切图谱和序列分析，结果表明所合成的水蛭素基因与设计完全一     

锥体虫,果蝇基因编码区的密码子使用,碱基间关联与基…

用自洽信息聚类方法预测了锥体虫（Ｔｒｙｐａｎｏｓｏｍａｂｒｕｃｅｉ）（８１个基因）和果蝇（Ｄｒｏｓｏｐｈｉｌａ）（１２４个基因）的基因表达水平，高表达基因同义密码子的使用规律，求出描述基因表达水平的参数ＩＥ值和ＣＡＩ值，在此基础上，用我们提出的基因表达增强网络（ＥＥＮ）理论研究了基因编码区的碱基构成，密码子内和密码子之间的碱基关联与基因表达水平的关系，结果表明，其增强网络位点数目比Ｅ．ｃｏｌｉ和Ｙ     

Analysis of correlations between protein complex and protein-protein interaction and mRNA expression

Protein-protein interaction is a physical interaction of two proteins in living cells. In budding yeast Saccharomyces cerevisiae, large-seale protein-protein interaction data have been obtained through high-throughput yeast two-hybrid systems (Y2H) and protein complex purification techniques based on mass-spectrometry. Here, we collect 11855 interactions between total 2617 proteins. Through seriate genome-wide mRNA expression data, similarity between two genes could be measured. Protein complex data can also be obtained publicly and can be translated to pair relationship that any two proteins can only exist in the same complex or not. Analysis of protein complex data, protein-protein interaction data and mRNA expression data can elucidate correlations between them. The results show that proteins that have interactions or similar expression patterns have a higher possibility to be in the same protein complex than randomized selected proteins, and proteins which have interactions and similar expression patterns are even more possible to exist in the same protein complex. The work indirates that comprehensive integration and analysis of public large-seale bioinformatical data, such as protein complex data, protein-protein interaction data and mRNA expression data, may help to uncover their relationships and common biological information underlying these data. The strategies described here may help to integrate and analyze other functional genomic and proteomic data, such as gene expression profiling, protein-localization mapping and large-scale phenotypic data, both in yeast and in other organisms.     

Characterization and mapping of a white panicle mutant gene in rice

A spontaneous white panicle mutant was found from the F6 progenies of an indicajaponica cross.The mutant exhibits white stripes on its basal leaves while the panicles,rachis and pedicel are milky white colored at flowering stage.Genetic analysis in an F2 population from the cross of Zhi7/white panicle mutant indicates that the white panicle phenotype is controlled by a single recessive nuclear gene,tentatively termed as wp(t).Using microsatellite markers,the wp(t) gene was anchored between the markers of SSR101 and SSR63.9 with a map distance of 2.3 and 0.8cM,respectively,and co-segregated with the marker of SSR17 on rice chromosome 1.     

中国人促红细胞生成素基因组的克隆及其在COS-7细胞中的表达

本文利用PCR技术,从正常人胎肝染色体DNA库中分离克隆了长度分别为506bp,465bp的中国人促红细胞生成素(EPO)基因组片段。506bp基因片段包括外显子2(信号肽),内含子2和外显子3;465bp片段包括外显子4,内含子4和外显子5。通过在引物中设置的酶切位点将两个克隆片段进行了正确的拼接,从而得到了约1.0kb的EPO次全基因组片段,它包括除信号肽中第2,3,4位氨基酸外的所有编码区及两个内含子序列。 所克隆的次全EPO基因组插入表达载体pSV2-dhfr中的不同克隆位点,构建了3种不同的转移载体质粒,分别转染导入COS-7细胞后,3种转移载体质粒转染的细胞上清液都有明显的EPO活性。本工作证明仅含有内含子2,4序列,去除负调控区和氧敏感区序列的人次全EPO基因组可以在COS-7细胞中获得表达。     

满江红鱼腥藻glnA启动子/GUS嵌合质粒在烟草中的表达

将满江红鱼腥藻ｇｌｎＡ启动区与ＧＵＳ报告基因连接,构成表达载体并导入烟草,在茎、叶中得到表达．这一结果为研究原核蓝藻与高等植物间转录因子识别、基因表达调控提供了有价值的信息,同时为构建实用载体开拓了新路．     

大肠杆菌SD序列与基因表达水平的关系

依据基因表达水平的理论预测方法从１３７３个大肠杆菌基因中选出了７３个甚高表达基因和１００个甚低表达基因,研究了这两类基因编码区起始密码子ＡＴＧ前－１到－２１位点（包含ＳＤ序列）的碱基构成与基因表达水平的关系。结果表明,ＳＤ序列中的富嘌呤区（约在－７到－１２位点）Ｇ和Ｔ的概率分布曲线中心到ＡＴＧ的距离（记为ＬＨ）与基因表达水平有明显的关系。甚高表达基因ＬＨ约为１０,甚低表达基因的ＬＨ约为８,另外在－