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351.
352.
土曲霉CCTCCAF93044植酸酶基因的克隆及序列分析 总被引:3,自引:0,他引:3
参考Hartingsvedt已发表的NRRL3135植酸酶(phyA)基因序列,设计并合成了一对引物,应用PCR技术,以土曲霉CCTCCAF93044总DNA为模板,扩增出了不包括假定的信号肽序列的phyA基因,并将其克隆到PMD18-T载体上,测定了其核苷酸序列,并推导了其氨基酸序列,该基因全长为1433bp,与已发表的NRRL3135的phyA基因的同源性为97%,编码一个含458个氨基物的蛋白质。 相似文献
353.
The function and usage of vMIPa encoded by K6 gene of herpesvirus 8 (HHV8) which has homology with human macrophage protein (MIP) have not been clearly known. In the present note the K6 gene of HHV8 was cloned and transfected into NIH3T3 cells and E. coli cells. Conditional media from the 3T3-transfected cells and K6 product vMIPa from E. coli . Cells were used to perform the experiments of ligand-receptor binding and cellular adhesion with peripheral blood macrophages. The conditional media and the purified vMIPa from E. coli could compete to bind to CCR5 located on macrophages from peripheral blood with I125-hMIP-1a chemokine of human. Cellular adhesion showed that the conditional media from transfected cells and the purified vMIPa did not induce the adhesion of macrophages from peripheral blood to ICAM-1. In conclusion, vMIPa encoded by K6 gene of HHV8 can bind to CCR5 of peripheral blood macrophage cells and does not induce their adhesion. This suggests that vMIPa enclosed CCR5, also known as HIV co-receptor, may be used to prevent and treat HIV infection. 相似文献
354.
Interspecific pregnancy in which the conceptus and female carrying the pregnancy are of different species is a key step to
interspecific cloning. Cloning endangered animals by interspecific pregnancy is such a highlight catching people’s eyes nowadays.
In this article, the history of interspecific pregnancy, the methods for establishment of interspecific pregnancy, the corresponding
theories, barriers and applied prospects are reviewed.
These authors contributed equally to this work. 相似文献
355.
HMW glutenin subunits in multiploidAegilops species: composition analysis and molecular cloning of coding sequences 总被引:1,自引:0,他引:1
The Aegilops genus contains species closely related to wheat. In common with wheat, Aegilops species accumulate high molecular weight (HMW) glutenin subunits in their endospermic tissue. In this study, we investigated the composition of HMW glutenin subunits in four multiploid Aegilops species using SDS-PAGE analysis. Furthermore, by working with Ae. ventricosa, we established an efficient genomic PCR condition for simultaneous amplification of DNA sequences coding for either x- or y-type HMW glutenin subunits from polyploid Aegilops species. Using the genomic PCR condition, we amplified and subsequently cloned two DNA fragments that may code for HMW glutenin subunits in Ae. ventricosa. Based on an analysis of the deduced amino acid sequences, we concluded that the two cloned sequences encode one x- and one y-type of HMW glutenin subunit, respectively. 相似文献
356.
通过鸟枪法克隆了甜菜夜蛾核多角体病毒(SeMNPV)基因组DNA EcoR I酶切的2.2kb片段,序列分析表明,该片段含有gp37基因,SeMNPV gp37基因的开放阅读框为801个核苷酸,编码268个氨基酸,预测蛋白质相对分子质量为30400,在gp37基因起始密码子上游有一典型的杆状病毒晚期基因启动子序列ATAAG,同其它昆虫杆状病毒和昆虫痘病毒GP37/Fusolin蛋白的比较结果表明,SeMNPV GP37与已知gp37/fusolin基因的氨基酸序列同源性较高(50-68%),在其蛋白序列内存在类似的保守区和可能的N-连接糖基化位点,在SeMNPV gp37基因下游存在一个完整阅读框和部分get基因序列。 相似文献
357.
产肠毒素大肠杆菌是与腹泻相关的一类大肠杆菌 ,肠毒素可分为耐热肠毒素和不耐热肠毒素。文章从肠毒素免疫性与作用机理 ,不耐热肠毒素的基因质粒、定位、亚基因克隆及表达 ,以及牛源大肠杆菌不耐热肠毒素等方面内容的国内外进展进行了讨论 相似文献
358.
Magnaporthe oryzae has been used as a primary model organism for investigating fungus-plant interaction. Many researches focused on molecular mechanisms of appressorium formation to restrain this fungal pathogen. Autophagy is a very high conserved process in eukaryotic cells. Recently, autophagy has been considered as a key process in development and differentiation in M. oryzae. In this report, we present and discuss the current state of our knowledge on gene expression in appressorium formation and the progress in autophagy of rice blast fungi. 相似文献
359.
360.
目的:探讨内皮型一氧化氮合酶基因(NOS3)的第4内含子串联重复序列多态性(eNOS4a/b)与原发性高血压患者左心室肥厚的关系.方法:采取病例对照研究,应用PCR技术对高血压患者(2179人,包括1061名左心室肥厚和1118名左心室非肥厚患者)及正常对照人群(812人)进行基因分型,并经测序验证;用a表示含有4个串联重复序列的基因型,用b表示含有5个串联重复序列的基因型.测量所有病例的超声参数.结果:NOS3的eNOS4a/b基因型频率符合Hardy-Weinberg平衡;a/a、a/b、b/b基因型频率在高血压肥厚、非肥厚患者及正常人群中分布分别为0.7%、12.5%、86.8%;0.5%、10.9%、88.6%和0.6%、12.8%、86.6%.a等位基因频率分别为6.9%、6.0%和7.0%,b等位基因频率分别为93.1%、94.0%和93.1%.各基因型频率与等位基因频率在三组之间无统计学差异(P>0.05).携带不同基因型的患者的临床指标和超声参数均无差异(P>0.05).结论:本研究认为NOS3的eNOS4a/b并不增加高血压继发左心室肥厚的易感性. 相似文献