检索结果-内蒙古大学图书馆

Comparative expression of homologous proteins -: A novel mode of transcriptional regulation by the coding sequence folding compatibility of chimeras

引用

JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第10期275卷 7304-7312页

作者： Morel, N Massoulié, J Ecole Normale Super Neurobiol Cellulaire & Mol Lab CNRS UMR 8544 F-75005 Paris France

Recombinant acetylcholinesterases (AChE) are produced at systematically different levels, depending on the enzyme species. To identify the cause of this difference, we designed expression vectors that differed only by the central region of the coding sequence, encoding Torpedo, rat, and Bungarus AChEs and two reciprocal rat/Bungarus and Bungarus/rat chimeras. We found that folding is a Limiting factor in the case of Torpedo AChE and the chimeras, for which only a limited fraction of the synthesized polypeptides becomes active and is secreted. In contrast, the fact that rat AChE is less well produced than Bungarus AChE reflects the levels of their respective mRNAs, which seem to be controlled by their transcription rates. A similar difference was observed in the coding and noncoding orientations;it seems to depend on multiple cis-elements. Using CAT constructs, we found that a DNA fragment from the Bungarus AChE gene stimulates expression of the reporter protein, whereas a homologous fragment from the rat AChE gene had no influence. This stimulating effect appears different from that of classical enhancers, although its mechanism remains unknown. In any case, the present results demonstrate that the coding region contributes to control the level of gene expression.

关键词：乙酰胆碱酯酶/生物合成乙酰胆碱酯酶/化学碱基序列环蛇属 COS细胞放线菌酮/药理学更生霉素/药理学基因表达调控遗传载体分子序列数据蛋白质折叠 RNA 信使/分析重组融合蛋白质类/生物合成电鳐转录遗传动物女(雌)性大鼠

来源：评论

学校读者我要写书评

暂无评论

Crystallization and preliminary X-ray analysis of the matrix protein from Ebola virus

引用

ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2000年第6期56卷 758-760页

作者： Dessen, A Forest, E Volchkov, V Dolnik, O Klenk, HD Weissenhorn, W European Mol Biol Lab F-38000 Grenoble France Inst Biol Struct Jean Pierre Ebel F-38027 Grenoble France Inst Virol D-35037 Marburg Germany

The matrix protein from Ebola virus is a membrane-associated molecule that plays a role in viral budding. Despite its functional similarity to other viral matrix proteins, it displays no sequence similarity and hence may have a distinct fold. X-ray diffraction quality crystals of the Ebola VP40 matrix protein were grown by the hanging-drop vapour-diffusion method. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 64.4, b = 91.1, c = 47.9 Angstrom, beta = 96.3 degrees. A data set to 1.9 Angstrom resolution has been collected using synchrotron radiation. The unit cell contains one molecule of molecular weight 35 kDa per asymmetric unit, with a corresponding volume solvent content of 35%.

关键词：结晶结晶学 X线埃博拉病毒/化学因子Ⅹa/遗传学遗传载体肽碎片/生物合成肽碎片/遗传学重组融合蛋白质类/生物合成重组融合蛋白质类/遗传学病毒基质蛋白质类/生物合成病毒基质蛋白质类/化学病毒基质蛋白质类/遗传学病毒基质蛋白质类/分离和提纯病毒蛋白质类/生物合成病毒蛋白质类/化学病毒蛋白质类/遗传学病毒蛋白质类/分离和提纯

来源：评论

学校读者我要写书评

暂无评论

Hypoxia-induced transcriptional activation of vascular endothelial growth factor is inhibited by serum

引用

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 2000年第1期267卷 334-338页

作者： D'Angelo, G Ladoux, A Frelin, C CNRS Inst Pharmacol Mol & Cellulaire UPR 411 F-06560 Valbonne France

Expression of vascular endothelial growth factor (VEGF) by cultured vascular smooth muscle cells was analyzed. Serum and hypoxia had nearly additive actions on VEGF mRNA expression. The function of the VEGF promoter in smooth muscle cells was analyzed using transient luciferase reporter assays. Serum and hypoxia stimulated expression of luciferase. The presence of hypoxia response element (HRE) was necessary for the hypoxic induction. AP-1 sequences located upstream of HRE and AP-S/Sp-1 sequences located downstream of HRE are not necessary. Hypoxic responses were best observed in serum-deprived cells. They were largely absent in serum-stimulated cells. Serum did not suppress the hypoxic response by interfering with the hypoxia sensor mechanism or with the signaling cascade that leads to the activation of HIF-1. It is concluded that growth-promoting cytokines regulate hypoxic gene induction in smooth muscle cells. (C) 2000 Academic Press.

关键词：主动脉血液细胞低氧/生理学细胞培养的培养基内皮生长因子/遗传学基因报告萤光素酶类/遗传学淋巴因子/遗传学肌平滑血管/生理学启动区(遗传学) RNA 信使/遗传学重组融合蛋白质类/生物合成信号传导反式激活(遗传学)/生理学转录遗传血管内皮生长因子A 血管内皮生长因子类动物兔

来源：评论

学校读者我要写书评

暂无评论

Yeast secretory expression of insulin precursors

引用

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY 2000年第3期54卷 277-286页

作者： Kjeldsen, T Novo Nordisk AS DK-2880 Bagsvaerd Denmark

Since the 1980s, recombinant human insulin for the treatment of diabetes mellitus has been produced using either the yeast Saccharomyces cerevisiae or the prokaryote Escherichia coli. Here, development of the insulin secretory expression system in S. cerevisiae and its subsequent optimisation is described. Expression of proinsulin in S. cerevisiae does not result in efficient secretion of proinsulin or insulin. However, expression of a cDNA encoding a proinsulin-like molecule with deletion of threonine(B30) as a fusion protein with the S. cerevisiae alpha-factor prepro-peptide (leader), followed either by replacement of the human proinsulin C-peptide with a small C-peptide (e.g. AAK), or by direct fusion of lysine(B29) to glycine(A1), results in the efficient secretion of folded single-chain proinsulin-like molecules to the culture supernatant. The secreted single-chain insulin precursor can then be purified and subsequently converted to human insulin by tryptic transpeptidation in organic-aqueous medium in the presence of a threonine ester. The leader confers secretory competence to the insulin precursor, and constructed (synthetic) leaders have been developed for efficient secretory expression of the insulin precursor in the yeasts S. cerevisiae and Pichia pastories. The Kex2 endoprotease, specific for dibasic sites, cleaves the leader-insulin precursor fusion protein in the late secretory pathway and the folded insulin precursor is secreted to the culture supernatant. However, the Kex2 endoprotease processing of the pro-peptide-insulin precursor fusion protein is incomplete and a significant part of the pro-peptide-insulin precursor fusion protein is secreted to the culture supernatant in a hyperglycosylated form. A spacer peptide localised between the leader and the insulin precursor has been developed to optimise Kex2 endoprotease processing and insulin precursor fermentation yield.

关键词：氨基酸序列 C肽/化学内质网/代谢分子序列数据肽类/化学肽类/遗传学肽类/代谢胰岛素原/生物合成胰岛素原/化学胰岛素原/遗传学胰岛素原/分泌前蛋白转化酶类蛋白分选信号重组融合蛋白质类/生物合成重组融合蛋白质类/化学重组融合蛋白质类/分泌酵母菌酿酒/遗传学酵母菌酿酒/代谢酿酒酵母蛋白质类枯草杆菌蛋白酶类/代谢人类

来源：评论

学校读者我要写书评

暂无评论

Popping a pill to regulate therapeutic protein delivery

引用

MOLECULAR MEDICINE TODAY 2000年第5期6卷 179-180页

作者： Sansom, C

来源：评论

学校读者我要写书评

暂无评论

Targeted transgene expression using the human HLA-DRA promoter in a retroviral vector

引用

TRANSPLANTATION PROCEEDINGS 2000年第5期32卷 1041-1042页

作者： Muthukumar, S Denaro, M Banerjee, PT White-Scharf, ME Andersson, G BioTransplant Inc Boston MA USA

来源：评论

学校读者我要写书评

暂无评论

Interleukin-1β suppresses retinoid transactivation of two hepatic transporter genes involved in bile formation

引用

JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第12期275卷 8835-8843页

作者： Denson, LA Auld, KL Schiek, DS McClure, MH Mangelsdorf, DJ Karpen, SJ Yale Univ Sch Med Dept Pediat New Haven CT 06520 USA Univ Texas SW Med Ctr Howard Hughes Med Inst Dallas TX 75235 USA Univ Texas SW Med Ctr Dept Pharmacol Dallas TX 75235 USA

Cytokines have been implicated in the pathogenesis of inflammatory cholestasis. This is due to transcriptional down-regulation of hepatic transporters including the Na+/bile acid cotransporter, ntcp, and the multispecific organic anion exporter, mrp2. We have recently shown that ntcp suppression by lipopolysaccharide in vivo is caused by down-regulation of transactivators including the previously uncharacterized Footprint B-binding protein. Both the ntcp FpB element and the mrp2 promoter contain potential retinoid-response elements. We hypothesized that retinoic acid receptor (RAR) and retinoid X receptor (RXR) heterodimers would activate these two genes and that cytokines that reduce bile flow might do so by suppressing nuclear levels of these transactivators. Retinoid transactivation and interleukin-1 beta down-regulation of the ntcp and mrp2 promoters were mapped to RXR alpha:RAR alpha-response elements. Gel mobility shift assays demonstrated specific binding of RXR alpha: RAR alpha heterodimers to the ntcp and mrp2 retinoid-response elements. The RXR alpha:RAR alpha complex was downregulated by IL-1 beta in HepG2 cells. An unexpected finding was that an adjacent CAAT-enhancer-binding protein element was required for maximal transactivation of the ntcp promoter by RXR alpha:RAR alpha. Taken together, these studies demonstrate regulation of two hepatobiliary transporter genes by RXR alpha:RAR alpha and describe a mechanism which likely contributes to their down-regulation during inflammation.

关键词：白蛋白类/遗传学阴离子转运蛋白质类胆汁/代谢载体蛋白质类/生物合成载体蛋白质类/遗传学胆汁淤积/病因学细胞因子类/药理学 DNA结合蛋白质类/代谢二聚作用白细胞介素1/药理学白细胞介素6/遗传学肝/代谢膜转运蛋白质类突变核蛋白质类/代谢有机阴离子转运子钠依赖启动区遗传蛋白质结合蛋白质亚型/代谢受体维甲酸/代谢重组融合蛋白质类/生物合成反应元件维甲类X受体维生素A酸类/药理学协同转运子转录因子/代谢转录激活动物人类大鼠

来源：评论

学校读者我要写书评

暂无评论

Activation of the luteinizing hormone β promoter by gonadotropin-releasing hormone requires c-Jun NH₂-terminal protein kinase

引用

JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第28期275卷 21639-21647页

作者： Yokoi, T Ohmichi, M Tasaka, K Kimura, A Kanda, Y Hayakawa, J Tahara, M Hisamoto, K Kurachi, H Murata, Y Osaka Univ Sch Med Dept Obstet & Gynecol Osaka 5650871 Japan

Regulation of the mitogen-activated protein kinase (MAPK) family by gonadotropin-releasing hormone (GnRH) in the gonadotrope cell line L beta T2 was investigated. Treatment with gonadotropin-releasing hormone agonist (GnRHa) activates extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK), Activation of ERK by GnRHa occurred within 5 min, and declined thereafter, whereas activation of JNK by GnRHa occurred with a different time frame, i.e. it was detectable at 5 min, reached a plateau at 30 min, and declined thereafter. GnRHa-induced ERK activation was dependent on protein kinase C or extracellular and intracellular Ca2+, whereas GnRHa-induced JNK activation was not dependent on protein kinase C or on extracellular or intracellular Ca2+. To determine whether a mitogen-activated protein kinase family cascade regulates rat luteinizing hormone beta (LH beta) promoter activity, we transfected the rat LH beta (-156 to +7)luciferase construct into L beta T2 cells. GnRH activated the rat LH beta promoter activity in a time-dependent manner. Neither treatment with a mitogen-activated protein kinase/ERK kinase (MEK) inhibitor, PD98059, nor cotransfection with a catalytically inactive form of a mitogen-activated protein kinase construct inhibited the induction of the rat LH beta promoter by GnRH, Furthermore, cotransfection with a dominant negative Ets had no effect on the response of the rat LH beta promoter to GnRH. On the other hand, cotransfection with either dominant negative JNK or dominant negative c-Jun significantly inhibited the induction of the rat LH beta promoter by GnRH. In addition, GnRH did not induce either the rat LH beta promoter activity in L beta T2 cells transfected stably with dominant negative c-Jun, These results suggest that GnRHa differentially activates ERK and JNK, and a JNK cascade is necessary to elicit the rat LH beta promoter activity in a c-Jun-dependent mechanism in L beta T2 cells.

关键词：细胞系酶抑制剂/药理学类黄酮物质/药理学基因表达调控/药物作用基因表达调控/生理学基因 jun 促性腺素释放激素/激动剂促性腺素释放激素/药理学促性腺素释放激素/生理学 JNK丝裂原活化蛋白激酶类动力学萤光素酶类/遗传学促黄体激素/遗传学丝裂原激活蛋白激酶类/代谢重组融合蛋白质类/生物合成十四酰佛波乙酯/药理学时间因素转染毒力因子鲍特菌属/药理学动物大鼠

来源：评论

学校读者我要写书评

暂无评论

GATA-6 activates transcription of surfactant protein A

引用

JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第2期275卷 1043-1049页

作者： Bruno, MD Korfhagen, TR Liu, C Morrisey, EE Whitsett, JA Childrens Hosp Med Ctr Div Pulm Biol Cincinnati OH 45229 USA Univ Penn Dept Med Philadelphia PA 19104 USA

Surfactant protein A (SP-A) is a member of the collectin family of innate host defense molecules expressed primarily in respiratory epithelial cells of the lung. SP-A concentrations are influenced by both cell-specific and ubiquitous nuclear proteins that regulate SP-A gene transcription in a cell-selective and temporally regulated manner. In this work, a consensus GATA-binding site (GBS) was identified at positions -69 to -64 of the mouse SP-A gene. The transcriptional activity of wildtype SP-A reporter constructs in HeLa cells was increased 5-10-fold when cotransfected with a GATA-6 expression plasmid, Deletion of the GBS completely blocked transactivation by GATA-6, Transfection of a construct expressing GATA-6-engrailed fusion protein inhibited basal expression of the SP-A/chloramphenicol acetyltransferase construct in MLE-15 cells. Nuclear extract proteins from MLE-15 cells bound to the GBS in the mouse SP-A gene, and a supershifted band was detected with a GATA-6-specific antibody. Transactivation of the wild-type SP-A constructs by GATA-6 increased transcriptional activity 7-10-fold, whereas thyroid transcription factor-1 (TTF-1) increased the activity of these constructs 12-18-fold. The effects of cotransactivating with both GATA-6 and TTF-1 expression constructs were additive. However, mutation of the TTF-1-binding sites alone or in combination decreased GATA-6 transactivation. Likewise, mutation of the GBS blocked TTF-1 activation of the SP-A promoter. In situ hybridization demonstrated GATA-6 mRNA in the peripheral epithelial cells of fetal mouse lung, consistent with the sites of SP-A expression. GATA-6 is expressed in respiratory epithelial cells and binds to a cis-acting element in the SP-A gene promoter, activating the transcriptional activity of the gene.

关键词：碱基序列细胞系细胞核/代谢氯霉素O-乙酰转移酶/遗传学保守序列 DNA结合蛋白质类/代谢 GATA6转录因子基因表达调控糖蛋白类/遗传学 HeLa细胞肺/胚胎学肺/代谢分子序列数据诱变定点核蛋白质类/代谢蛋白脂质类/遗传学肺表面活性物质相关蛋白质A 肺表面活性物质相关蛋白质类肺表面活性剂/遗传学重组融合蛋白质类/生物合成重组蛋白质类/生物合成呼吸道黏膜/代谢序列比对序列同源性核酸转录因子/代谢转录遗传转录激活转染锌指动物人类小鼠大鼠

来源：评论

学校读者我要写书评

暂无评论

Protein kinase-A dependent phosphorylation of transcription enhancer factor-1 represses its DNA-binding activity but enhances its gene activation ability

引用

NUCLEIC ACIDS RESEARCH 2000年第16期28卷 3168-3177页

作者： Gupta, MP Kogut, P Gupta, M Univ Chicago Dept Surg Cardiac & Thorac Chicago IL 60637 USA Univ Illinois Dept Physiol & Biophys Chicago IL 60612 USA

The cAMP-dependent signaling pathway has been implicated in cardiac cell growth/differentiation and muscle gene transcription, Previously, we have identified a cAMP-inducible E-box/M-CAT hybrid motif in the cardiac alpha-myosin heavy chain (alpha-NHC) gene promoter. The two factors, TEF-1 and Max, that bind to this motif are found to physically associate with each other and exert a positive cooperative effect for gene regulation, Here we show that TEF-1, but not Max, is a substrate for protein kinase-A (PK-A)-dependent phosphorylation. TEF-1 is phosphorylated by PK-A at residue serine-102, This post-translational modification of TEF-1 repressed its DNA-binding activity, but not its ability to interact with the Max protein, Replacement of serine-102 in TEF-1 by a neutral or a charged amino acid did not abolish its DNB-binding ability, suggesting that changing a charge at the 102 amino-acid position of TEF-1 was not sufficient to inhibit its DNA-binding activity, We also show that PK-A response of the alpha-MHC gene is stimulated by the presence of wild-type TEF-1 but not by mutant TEF-1 having serine-102 replaced by alanine, suggesting that phosphorylation at this residue accounts for the cAMP/PK-A response of the gene, Thus, these data demonstrate that TEF-1 is a direct target of cAMP/PK-A signaling in cardiac myocytes.

关键词：氨基酸序列碱基序列碱性螺旋-环-螺旋亮氨酸拉链转录因子类碱性亮氨酸拉链转录因子类细胞核/代谢细胞培养的环AMP依赖性蛋白激酶类/代谢 DNA结合蛋白质类/化学 DNA结合蛋白质类/遗传学 DNA结合蛋白质类/代谢胎儿基因表达调控谷胱甘肽转移酶/遗传学动力学分子序列数据心肌/细胞学心肌/代谢核蛋白质类磷酰化重组融合蛋白质类/生物合成重组融合蛋白质类/化学序列比对序列同源性氨基酸丝氨酸/代谢转录因子/化学转录因子/遗传学转录因子/代谢转录激活转染动物人类小鼠大鼠

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：