hKv4.3基因5′非翻译区序列S160功能分析

hKv4.3基因是形成瞬时外向钾电流Ito的主要分子基础,它在心脏和神经细胞中大量表达,但在其它组织中则未见大量表达.为了研究hKv4.3表达在基因水平的调节,将hKv4.3基因的5′非翻译区的一段序列( 2~ 160,称之为S160)克隆到报告质粒中,进行瞬时表达.发现S160对hKv4.3基因的启动子和SV40的启动子都有强烈的抑制作用,没有方向特异性,但却有位置特异性.经删除突变分析,在S160片段中发现了一个抑制元件S(GAGGGGTTAA),它位于hKv4.3基因中转录起始位点下游20~30bp处.在此基础上,用RT-PCR方法对mRNA进行定量分析,初步确认这个抑制元件对蛋白表达的抑制过程是在翻译水平上.     

hKv4.3基因5'非翻译区序列S160功能分析

hKv4.3基因是形成瞬时外向钾电流Ito的主要分子基础, 它在心脏和神经细胞中大量表达, 但在其它组织中则未见大量表达. 为了研究hKv4.3表达在基因水平的调节, 将hKv4.3基因的5'非翻译区的一段序列(+2~+160, 称之为S160)克隆到报告质粒中, 进行瞬时表达. 发现S160对hKv4.3基因的启动子和SV40的启动子都有强烈的抑制作用, 没有方向特异性, 但却有位置特异性. 经删除突变分析, 在S160片段中发现了一个抑制元件S(GAGGGGTTAA), 它位于hKv4.3基因中转录起始位点下游20-30 bp处. 在此基础上, 用RT-PCR方法对mRNA进行定量分析, 初步确认这个抑制元件对蛋白表达的抑制过程是在翻译水平上.     

hKv4.3基因5＇非翻译区序列S160功能分析

hKv4.3基因是形成瞬时外向钾电流Ito的主要分子基础,它在心脏和神经细胞中大量表达,但在其它组织中则未见大量表达。为了研究hKv4.3表达在基因水平的调节,将hKv4.3基因的5＇非翻译区的一段序列（＋2～＋160,称之为S160）克隆到报告质粒中,进行瞬时表达。发现S160对hKv4.3基因的启动子和SV40的启动子都有强烈的抑制作用,没有方向特异性,但却有位置特异性。经删除突变分析,在S160片段中发现了一个抑制元件S（GAGGGGTTAA）,它位于hKv4.3基因中转录起始位点下游20～30 bp处。在此基础上,用RT-PCR方法对mRNA进行定量分析,初步确认这个抑制元件对蛋白表达的抑制过程是在翻译水平上。     

Isolation and Functional Characterization of a Novel Seed-Specific Promoter Region from Peanut

The importance of using tissue-specific promoters in the genetic transformation of plants has been emphasized increasingly. Here, we report the isolation of a novel seed-specific promoter region from peanut and its validation in Arabidopsis and tobacco seeds. The reported promoter region referred to as groundnut seed promoter (GSP) confers seed-specific expression in heterologous systems, which include putative promoter regions of the peanut (Arachis hypogaea L.) gene 8A4R19G1. This region was isolated, sequenced, and characterized using gel shift assays. Tobacco transgenics obtained using binary vectors carrying uidA reporter gene driven by GSP and/or cauliflower mosaic virus 35S promoters were confirmed through polymerase chain reaction (PCR), RT-PCR, and computational analysis of motifs which revealed the presence of TATA, CAAT boxes, and ATG signals. This seed-specific promoter region successfully targeted the reporter uidA gene to seed tissues in both Arabidopsis and tobacco model systems, where its expression was confirmed by histochemical analysis of the transgenic seeds. This promoter region is routinely being used in the genetic engineering studies in legumes aimed at targeting novel transgenes to the seeds, especially those involved in micronutrient enhancement, fungal resistance, and molecular pharming.     

A Minimal Functional Complex of Cytochrome P450 and FBD of Cytochrome P450 Reductase in Nanodiscs

Structural interactions that enable electron transfer to cytochrome‐P450 (CYP450) from its redox partner CYP450‐reductase (CPR) are a vital prerequisite for its catalytic mechanism. The first structural model for the membrane‐bound functional complex to reveal interactions between the full‐length CYP450 and a minimal domain of CPR is now reported. The results suggest that anchorage of the proteins in a lipid bilayer is a minimal requirement for CYP450 catalytic function. Akin to cytochrome‐b₅ (cyt‐b₅), Arg 125 on the C‐helix of CYP450s is found to be important for effective electron transfer, thus supporting the competitive behavior of redox partners for CYP450s. A general approach is presented to study protein–protein interactions combining the use of nanodiscs with NMR spectroscopy and SAXS. Linking structural details to the mechanism will help unravel the xenobiotic metabolism of diverse microsomal CYP450s in their native environment and facilitate the design of new drug entities.     

一种新型脱氧核糖核酸序列表征子及其应用于E.coli启动子对RNA转录启动强度的QSAM研究

从天然碱基的36种性质参数出发,通过主成分分析(PCA)技术处理得到了1个显著的主成分得分,并将该得分作为单个碱基的信息描述子———VBPV。进而使用VBPV对38个大肠杆菌(E.coli)启动子序列一级结构进行表征,并结合多元统计方法将表征参数与转录启动强度(PS)成功地建立了定量序列活性模型(QSAM),该模型拟合复相关系数Rcum与交叉检验复相关系数Qcum分别为0.97和0.95。     

人参对金黄色葡萄球菌的代谢过程促进作用的研究

前文[1]已报导了合成药物对细菌抑制作用的研究．药物抑菌生长的热化学研究是当今热化学法研究的一个活跃领域，Boling[2]、Nordmark[3]等人已做了很有意义的工作．在此基础上，作者对畜养药物促进细菌代谢过程进行了研究，用微量量热仪测定了人参对金黄色葡萄球菌代谢过程起促     

黄芪促菌作用的微量热法研究

黄芪促菌作用的微量热法研究李志萍，杭瑚，陆懋荪于秀芳，张洪林袁久荣（青岛大学化学系青岛２６６０７１）（曲阜师范大学化学系曲阜）（山东中医学院中药系济南）关键词黄芪，促菌作用，量热法前文［１～３］已报道合成药物及中草药黄连对细菌生长的抑制作用。本文研究...     

Proteome Analysis: A Pathway to the Functional Analysis of Proteins

The protein equivalent of genomes , proteomes are quantitative protein patterns of an organism, a cell, or a body fluid, and are determined by the development state and environmental parameters. Changes in protein expression and their consequences can be investigated at the molecular level and provide biologically relevant information not obtainable from experiments with mRNA.