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为探索热胁迫对丹参迷迭香酸途径关键酶基因表达的影响,采用定量RT-PCR法,以Actin与GAPDH作为内参基因,0~48h叶片cDNA作为模板,对迷迭香酸途径7个关键酶基因PAL、C4H、4CL、TAT、HPPD、HPPR和RAS的表达进行分析。通过试验结果构建出这7个关键酶基因0~48h代谢途径表达图谱。其中,PAL、C4H和RAS受热胁迫影响表达量下降;TAT、4CL和HPPD表达量呈先上升后下降趋势;HPPR表达量前期变化不大,后期呈下降趋势。结果表明热胁迫对迷迭香酸途径关键酶基因表达有极显著影响。该表达时序谱的建立为进一步研究热胁迫与酚酸类成分累积之间的关系奠定了基础。 相似文献
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Antioxidant capacity manipulation in transgenic potato tuber by changes in phenolic compounds content 总被引：1，自引：0，他引：1
Lukaszewicz M Matysiak-Kata I Skala J Fecka I Cisowski W Szopa J 《Journal of agricultural and food chemistry》2004,52(6):1526-1533
The main goal of this study was to generate potato tubers with increased levels of flavonoids and thus modified antioxidant capacities. To accomplish this, the vector carrying multigene construct was prepared and several transgenic plants were generated, all overexpressing key biosynthesis pathway enzymes. The single-gene overexpression or simultaneous expression of genes encoding chalcone synthase (CHS), chalcone isomerase (CHI), and dihydroflavonol reductase (DFR) resulted in a significant increase of measured phenolic acids and anthocyanins. The increase in phenolic compounds synthesis is accompanied by decreases in starch and glucose levels in transgenic plants. The flavonoids-enriched plants showed improved antioxidant capacity; however, there is a complex relationship between antioxidant capacity and flavonoids content, suggesting the great participation of other compounds in the antioxidant potential of the plants. These other compounds are not yet recognized. 相似文献
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Berries are known to contain phenolic substances (i.e., flavonoids and phenolic acids), which comprise two large and heterogeneous groups of biologically active nonnutrients. This investigation evaluated the content and profile of the phenolic compounds present in six different berries found in Northern Europe. The latter included bilberry (Vaccinium myrtillus), cowberry (Vaccinium vitis-idaea), cranberry (Vaccinium oxycoccus), strawberry (Fragaria ananassa), black currant (Ribes nigrum), and red currant (Ribes rubrum). The study was focused on two areas. The first involved the extraction and analysis of berries for total phenolic content and determination of their antioxidant activity. The total phenolic level of berries was correlated with their antioxidant activity. Second, the berry extracts were analyzed by capillary electrophoresis to determine the content and profile of selected bioactive compounds. The analytes of interest included trans-resveratrol, cinnamic acid, ferulic acid, p-coumaric acid, quercetin, and morin. 相似文献
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The biosynthesis of the monoterpene (S)-linalool and the sesquiterpene trans-(S)-nerolidol in fruits of Fragaria x ananassa Duch. cv. Eros and Florence and of the monoterpene (-)-alpha-pinene in Fragaria vesca was investigated by in vivo feeding experiments with [5,5-2H2]mevalonic acid lactone (d2-MVL) and [5,5-2H2]-1-deoxy-d-xylulose (d2-DOX). The feeding experiments indicate that (S)-linalool and trans-(S)-nerolidol in Fragaria x ananassa Duch. and (-)-alpha-pinene in F. vesca are exclusively synthesized via the cytosolic mevalonic acid pathway without any contribution from the plastidial 1-deoxy-D-xylulose/2-C-methyl-D-erythritol 4-phosphate (DOXP/MEP) route. Inhibition experiments revealed that even the presence of mevastatin, an export of plastid-derived isopentyl diphosphate/dimethylallyl diphosphate, cannot be induced. However, the enantioselective analysis shows that in Fragaria x ananassa Duch. cv. Eros and Florence both linalool enantiomers are present and that only (S)-linalool is labeled after administration of d2-MVL. Therefore, the origin of (R)-linalool in these fruits remains unknown. Contrarily, in Fragaria x ananassa Duch. foliage (R)-linalool is the dominant enantiomer. Feeding experiments revealed an incorporation of d2-MVL and d2-DOX at equal rates exclusively into (S)-linalool. Only in F. vesca foliage, where (R)-linalool is present at high enantiomeric purity (ee > 90%), is a de novo biosynthesis of the (R)-enantiomer via the DOXP/MEP pathway detectable. These results demonstrate a complex intraplant variation of (R)- and (S)-linalool biosynthesis via the cytosolic and plastidial route. 相似文献
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Compost as a soil supplement significantly enhanced levels of ascorbic acid (AsA) and glutathione (GSH) and ratios of AsA/dehydroascorbic acid (DHAsA) and GSH/oxidized glutathione (GSSG) in fruit of two strawberry (Fragaria x ananassa Duch.) cultivars, Allstar and Honeoye. The peroxyl radical (ROO(*)) as well as the superoxide radical (O(2)(*)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radical (OH(*)), and singlet oxygen ((1)O(2)) absorbance capacity in strawberries increased significantly with increasing fertilizer strength and compost use. The planting medium (compost) x fertilizer interaction for phenolics and flavonoids was significant. Fruit from plants grown in full-strength fertilizer with 50% soil plus 50% compost and 100% compost yielded fruit with the highest levels of phenolics, flavonol, and anthocyanin content. A positive relationship between antioxidant activities and contents of AsA and GSH and ratios of AsA/DHAsA and GSH/GSSG existed in fruit of both strawberry cultivars. Correlation coefficients for the content of antioxidant components versus antioxidant activity [against ROO(*), O(2)(*)(-), H(2)O(2), OH(*), or (1)O(2)] ranged from r( )()= 0.7706 for H(2)O(2) versus GSH/GSSH in cv. Allstar to r = 0.9832 for O(2)(*)(-) versus total flavonoids in cv. Allstar. 相似文献
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甜瓜性别分化是由多因素构成的一个复杂的网络系统调控,受到多种环境因素及激素水平的影响。本研究利用甜瓜(Cucumis melo L.)WI 998×TopMark 构建重组自交系群体,通过第二代高通量测序技术对F2S6群体中雌雄异花同株及全雌系植株的转录组测序,比较差异表达基因,分析与性别差异表达相关的植物激素合成途径。结果显示,雌雄异花同株获得77376 条 Unigenes,平均长度为 435 bp;全雌系转录组测序获得 80 825 条 unigenes,平均长度为 509 bp。比较雌雄异花同株与全雌系转录组,发现共有 8966个基因差异表达,4 296 个基因下调,4 670 个基因上调。对差异基因进行基因本体论(GO)功能分类,发现2 352 条 Unigenes 归入到生物学过程,4 107 条 Unigenes 归入到细胞学过程,2 507 条 Unigenes 归入到分子功能。差异表达基因共参与 121 个 Pathway,发现赤霉素(gibberellin, GA)合成途径中 GA3 - 氧合成酶(GA3-ox)(MU3674)、GA7- 氧化酶(GA7-ox)(MU36987)、GA2- 氧化酶(GA2-ox)(MU13098/MU13099)、GA20-氧化酶(GA20-ox)和 GA2- 氧化酶(GA2-ox)(MU33020)等基因差异表达;共有 38 个基因在脱落酸(abscisicacid, ABA)合成途径中差异表达,其中 19 个上调,19 个下调;油菜素内酯(brassinolide, BR)合成途径中,MU22012 (cytochrome P450),MU26893 (cytochrome P450) 基因上调 ,MU56098 (cytochrome P450,CYP724B3),MU76596(CYP724A1)下调。本研究还发现参与甜瓜性别表达,分别与赤霉素、脱落酸、油菜素内酯及玉米素等多种激素合成、信号传导等代谢途径相关。研究结果为分析甜瓜决定性别分化的可能机理,为下一步研究甜瓜性别修饰基因的克隆,提供重要依据。 相似文献
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Wei Liu Da-Hui Liu Ming-Jian Geng Te-Wu Yang Xiao Wang 《Journal of plant nutrition》2015,38(6):868-885
The aim of this paper is to study the influence of P deficiency on secondary metabolites of flavonoid in Chrysanthemum morifolium Ramat. The regression equation between flavonoid and phenolic acid content was Y = ?294.46X + 150.66 (R2 = 0.9205, P < 0.01) in check and Y = 42.62X + 2.49 (R2 = 0.9564, P < 0.01) in P deficient treatment (Y, flavonoid content; X, phenolic content). There were two principal components to control the flavonoid major synthesis process, that was principal 1 [phenolic acid, phenylalanine ammonia-lyase (PAL), cinnamic acid and p-coumaric acid] (88.17%) and principal 2 [4-coumarate coenzyme A ligase (4CL), Cinnamate-4-hydroxylase (C4H)] (9.64%) domination under normal growth of C. moriloium. However, under P deficiency condition, the principal components were principal 1 (phenolic acid, cinnamic acid and p-coumaric acid and C4H) (81.46%) and principal 2 (PAL) (18.53%) domination, respectively. The influence of P deficiency on flavonoid major synthesis pathway was caused by the change of PAL and C4H activities. 相似文献
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Lunkenbein S Coiner H de Vos CH Schaart JG Boone MJ Krens FA Schwab W Salentijn EM 《Journal of agricultural and food chemistry》2006,54(6):2145-2153
An octaploid (Fragaria x ananassa cv. Calypso) genotype of strawberry was transformed with an antisense chalcone synthase (CHS) gene construct using a ripening related CHS cDNA from Fragaria x ananassa cv. Elsanta under the control of the constitutive CaMV 35S promoter via Agrobacterium tumefaciens. Out of 25 transgenic lines, nine lines showed a reduction in CHS mRNA accumulation of more than 50% as compared to the untransformed cv. Calypso control. The antisense CHS construct was found to be integrated into the genome, with a copy number ranging from one to four. The pigmentation of the fruit was only affected when less than 5% of the control CHS expression level was detected. A stable antisense phenotype over a period of 4 years was obtained in the primary transgenic lines at a rate of 1:20. As a consequence of the reduced activity of CHS, the levels of anthocyanins, flavonols, and proanthocyanidins were downregulated and precursors of the flavonoid pathway were shunted to the phenylpropanoid pathway leading to highly increased levels of cinnamoyl glucose (520% of control), caffeoyl glucose (816% of control), and feruloyl glucose (1092% of control) as well as p-coumaryl alcohol (363% of control) and p-coumaryl-1-acetate (1079% of control), which occur only as trace components in untransformed control fruits. These results demonstrate that the introduction of an antisense CHS construct in strawberry results in an unpredictable biochemical phenotype, thereby confirming that CHS function is an important regulatory point of substrate flow between the flavonoid and the phenylpropanoid pathways. 相似文献
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采用营养钵土培的方法,研究了外源苯丙烯酸对津美1号、绿衣天使、C90和翠龙等不同黄瓜品种幼苗生长和叶片抗氧化酶活性及活性氧代谢的影响。结果表明,外源苯丙烯酸胁迫对黄瓜幼苗生长具有很强的抑制作用,并随着胁迫浓度的增大受抑制的程度加强。在苯丙烯酸胁迫下,黄瓜叶片的超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）活性表现为低浓度升高,高浓度下降的趋势;超氧阴离子（O2-.）产生速率、过氧化氢（H2O2）含量、膜脂过氧化产物丙二醛（MDA）含量及渗透调节物质脯氨酸（Pro）含量、可溶性糖含量随着苯丙烯酸浓度的升高而显著增加。不同黄瓜品种对苯丙烯酸胁迫的响应存在着品种间差异。 相似文献
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乳酸菌胞外多糖能显著改善发酵乳制品及食品的流变学和质构特性。为进一步了解乳酸菌胞外多糖的生物合成途径及调控机制,本研究对参与植物乳杆菌C88胞外多糖生物合成基因簇的部分序列进行了克隆和鉴定。根据GenBank中己报道植物乳杆菌基因序列的保守区域设计特异性引物,扩增出植物乳杆菌C88生物合成蛋白基因（cps4A）序列,并通过染色体步移方法克隆了植物乳杆菌C88参与胞外多糖合成基因簇的部分序列（4．9kb）。利用生物信息学方法预测基因簇中6个阅读框的结构和功能,结果表明该序列与己报道的乳酸杆菌胞外多糖生物合成基因具有高度的同源性（〉96％）;对各阅读框功能预测分析发现,这6个基因主要编码参与胞外多糖合成中的多糖合成蛋白、糖链长度检测蛋白、UDP-葡萄糖-4-异构酶和糖基转移酶。本研究将为利用基因工程方法调控多糖的合成和产量提供理论依据。 相似文献
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为探究水分胁迫对葡萄果实白藜芦醇合成的影响,本研究以赤霞珠为试验材料,对其进行不同程度水分胁迫处理,测定葡萄果实白藜芦醇含量及白藜芦醇生物合成相关基因表达量。结果表明,葡萄果实进入转色期,PAL、4CL、STS基因随白藜芦醇合成而大量表达;不同水分胁迫处理均能增加葡萄果实白藜芦醇含量,同时提高白藜芦醇合成相关基因的表达量,不同水分胁迫处理间存在差异;水分胁迫对果实转色前期和后期PAL、STS基因表达的促进作用最为显著,但水分胁迫显著降低了CHS基因的表达量。相关性分析表明,白藜芦醇含量与PAL、STS基因的表达量呈显著正相关,表明水分胁迫主要通过诱导PAL、STS基因表达来增加果实白藜芦醇含量。本研究结果为进一步阐明葡萄白藜芦醇合成调控机制奠定了理论基础。 相似文献
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In experiments involving feeding, significant amounts of ring radioactively-laheled cinnamic and quinic acids were respired as 14CO2 by the terrestrial isopod Oniscus asellus L.In experiments involving injection, approximately 25% of ring radioactively-labelcd cinnamic acid, phenol and quinic acid were recovered as respiratory 14CO2 during 7 days at 15°C. Less than, or about, 1% of the dose was present in feces and sand occupied by the animal. Only 0. 10 and 4% respectively of the cinnamic acid, phenol and quinic acid were recovered from the body unchanged after 7 days. It is not known whether the test compounds were metabolized by animal oxidases or internal microbes. 相似文献
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乙烯生物合成途径中的两个关键酶基因的研究进展 总被引：6，自引：0，他引：6
本文对植物激素乙烯生物合成途径中的两个关键酶基因即ACC合成酶基因(ACS)和ACC氧化酶基因(ACO)的克隆研究现状、表达及反馈调节等方面进行了评述。 相似文献
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The antioxidant capacity (AOC) of three representative citrus limonoids, limonin, nomilin, and limonin glucoside, was examined by the oxygen radical absorbance capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), beta-carotene-linoleic acid bleaching, and 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assays. Pure compounds and proper negative (cinnamic acid) and positive (2,6-di-tert-butyl-4-methylphenol (BHT) and ascorbic acid) controls were used to remove any ambiguity in interpreting results. In all cases, limonin and nomilin gave results equivalent to those of cinnamic acid, indicating that they do not possess any inherent AOC and should not be considered antioxidants. Similar results were observed for limonin glucoside, with the exception of an anomalous result obtained from the beta-carotene-linoleic acid bleaching assay. Limonin glucoside was deemed not to be an antioxidant on the basis of the three unequivocal assays. 相似文献