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1.
MicroRNAs(miRNAs)通过使靶mRNA降解或翻译参与生物体的转录后调控,并在植物对生物与非生物胁迫的应答过程中发挥重要作用。本研究基于相关数据库,利用生物信息学方法,通过搜索预测及实验验证得到甜杨(Populus suaveolens)低温响应miR475的12条潜在靶基因,并对其降解位点进行分析;同时,以低温(0℃)处理不同时间甜杨幼苗为试材,利用荧光定量PCR对miR475及其靶基因的表达谱进行检测分析,结果发现,随着低温诱导时间的延长,miR475表达量呈下调趋势,而其靶mRNA的表达量则呈现相反趋势,表明甜杨miR475可能以降解靶mRNA的方式在抵御低温中发挥作用。本文研究结果可为甜杨抗冻机制的后续深入研究提供科学依据。  相似文献   

2.
microRNAs(miRNAs)是真核生物中一类长约22 nt的非编码小分子RNA,它通过对靶mRNA的切割或抑制靶mRNA的翻译调控基因的表达,从而对靶基因实施转录后水平负调控,在植物器官的形态建成、生长发育、信号转导及植物对逆境胁迫的应答中起着重要的作用。miR168是植物特有的一类RNA小分子,其主要的靶基因AGO1蛋白是RNA沉默复合体的重要组成成分,广泛参与对靶mRNA的剪切。本文综述了miR168的发现及其在植物中的分布、miR168与AGO1蛋白的关系、miR168对逆境胁迫的响应以及其在动植物间的跨界调节等,为进一步帮助人们了解miR168的功能及其参与动植物间跨界调节这一特性奠定良好的基础。  相似文献   

3.
葡萄糖-6-磷酸脱氢酶是磷酸戊糖途径的关键性调控限速酶,其主要功能是为脂肪酸合成、氮还原和谷胱甘肽等生物分子合成提供还原力NADPH,也为核酸合成提供戊糖;此外,还参加非生物逆境胁迫应答反应。因此,G6PDH对植物的生长发育起着非常重要的作用。本文利用甜杨G6PDH基因和毛果杨基因组序列,通过PCR获得了甜杨G6PDH基因上游1400bp的序列。序列分析结果表明,该序列具有启动子的基本元件TATA-box、CAAT-box。此外,还包含多个胁迫诱导元件,如低温诱导元件LTR,盐诱导元件GT-1,抗冻、缺水、脱落酸、抗寒元件MYB和MYC,以及光响应元件L-box、G-box、3AF-1、TC丰富区等。  相似文献   

4.
为明确MIR319家族成员(miR319、miR319a及miR319a-3p)在黄瓜绿斑驳花叶病毒(CGMMV)胁迫应答中的作用,本研究将MIR319的成熟序列与西瓜基因组进行Blast比对获得其前体基因,利用MEGA对前体基因进行系统进化分析,PlantCARE对前体基因启动子区的顺式作用元件进行分析,降解组测序对MIR319的靶基因进行分析,转录组测序及qRT-PCR分析MIR319靶基因的表达模式。研究结果获得MIR319家族成员共同前体基因Pre-MIR319,其长度为170 bp,含有完整的茎环结构;序列比对显示,MIR319家族成熟序列在5'端第2~第14位碱基高度保守;西瓜Pre-MIR319与35个物种的116条miR319前体序列经系统进化分析后分为四个分支,其中西瓜Pre-MIR319与马铃薯miR319a前体基因(MI0025952)距离最近;Pre-MIR319启动子区含有光响应元件、赤霉素响应元件、乙烯响应元件、茉莉酸甲酯响应元件、MYB和MYC等多个顺式作用元件;降解组测序获得MIR319家族成员的5个靶基因,其中Cla019567、Cla013523、Cla023342和Cla002428注释为TCP转录因子,Cla013668注释为MYB转录因子,剪切位点位于MIR319家族成员成熟序列5'端的第10位碱基;靶基因编码氨基酸数目为319~554 aa、分子量为34.94~61.21 kDa、理论等电点为5.29~7.80,定位于细胞核/细胞质中,均不含跨膜结构域;转录组测序及qRT-PCR分析表明miR319a负调控靶基因Cla013523(TCP)的表达。本研究结果进一步明确了MIR319家族成员在CGMMV胁迫应答中的作用及其对靶基因的调控作用。  相似文献   

5.
过氧化还原蛋白(Prxs)是广泛存在于植物体内重要的抗氧化酶。为深入研究Prx基因在苦瓜非生物胁迫中的作用,从苦瓜叶片均一化文库中获得McPrx基因的cDNA全长序列,并命名为McPrx(KJ722768.1),该cDNA序列全长1 068 bp,开放阅读框972 bp,编码324个氨基酸,属于ClassⅢ基因家族成员。采用基因组步移法分离获得McPrx基因5'上游1 237 bp的启动子调控序列,运用Plant CARE对其进行顺式作用元件分析,结果显示该序列除含有CAAT-box、TATA-box等核心启动子元件,还具有激素、抗病与抗逆应答元件,表明McPrx基因的表达可能受多种外界环境条件的调控。qRT-PCR分析表明,McPrx在根、茎、雌花等器官中的表达量存在极显著差异。其中在茎中表达量最大,在雌花中表达量最低,说明该基因的表达具有器官表达特异性;低温胁迫1 h时,McPrx表达量显著上调,胁迫3 h时McPrx表达量达到最大,随后下降,说明McPrx响应了低温胁迫的应答。本研究结果为进一步研究McPrx的生物学功能及其应用奠定了基础。  相似文献   

6.
GRX基因家族是从原核生物到真核生物中普遍存在的一类巯基-二硫键氧化还原酶,在植物的生长发育、器官构建及逆境胁迫和激素信号应答中均发挥重要作用.本研究在番茄基因组范围内,利用生物信息学方法对番茄的GRX基因组家族的成员、分布及结构和功能等进行分析.预测结果显示,番茄GRX家族包含55个蛋白质,分为4个亚族,其中植物特有的CC亚族成员最多,有35个,其他GRX基因成员与拟南芥GRX家族具有相似分类.在番茄GRX结构域中包含12个重要的基序,主要分布在序列的N端,相同亚族中的GRX成员蛋白序列的氨基酸保守域构成基本一致,且各亚族成员的氨基酸保守域组成特异,表明这些基序的存在对GRX蛋白功能的执行是必需的.利用实时荧光定量PCR对番茄GRX基因的组织表达和胁迫响应分析,结果表明,GRX基因具有组织特异性表达差异,CC型在根和花中表达较高,在果实中表达较低;在盐、SA、ABA、高温和低温胁迫条件下,22个番茄GRX基因的表达模式被阐明;其中部分基因的表达水平被显著地诱导增加或者降低,很可能参与了调控番茄逆境胁迫条件下的防御应答反应.本研究结果将为番茄GRX家族基因的深入研究提供依据,为进一步解析GRX基因功能奠定基础.  相似文献   

7.
SEP(SEPALLATA)类基因属于花器官发育ABCDE模型中的E类基因,拟南芥中的研究表明该类基因可能具有控制花器官形态发育以及激活其它类型基因的功能,是一类花发育过程中的关键基因。因此,研究杨树SEP类基因启动子表达特性对于杨树的开花调控研究具有重要意义。本文根据毛白杨SEP3基因和毛果杨基因组序列设计引物,通过PCR获得了PtSEP3-1,基因上游2000bp的序列。序列分析结果表明该序列具有启动子的基本元件TATA—box和CAAT-box,还包含大量光响应元件ACE、BoxI和Box4等,此外还有脱落酸响应元件ABRE,赤霉素响应元件GARE—motif以及胁迫响应元件HSE、TC—richrepeats等。进一步构建了一个以PtSEP3-1启动子驱动GUS基因的植物表达载体pPtSEP3-1,protest,为该启动子的功能鉴定奠定了基础。  相似文献   

8.
热胁迫下水稻miR396家族及靶基因OsGRFs的表达研究   总被引:1,自引:0,他引:1  
miRNA是真核生物体内一类非编码的小RNA,在动植物发育过程中发挥重要作用,但迄今为止,其在水稻耐高温方面的分子机理研究很少。为进行水稻(Oryza sativa)高温胁迫下miRNA的功能研究,前期通过小RNA测序发现,miR396家族是响应水稻高温胁迫最显著的家族。为了进一步研究miR396家族响应高温胁迫的分子机制,本研究对水稻日本晴(Oryza sativa spp.japonica cv.Nipponbare)苗期叶片进行不同时间48℃高温处理,通过q RT-PCR法分析8个miR396家族成员以及12个预测的靶基因生长调节因子(growth regulating factor,GRF)家族的表达情况。结果显示,miR396家族8个成员及12个预测靶基因对高温胁迫应答不同。miR396a、miR396e和miR396f在每个时间的高温胁迫呈上升表达,而miR396b,miR396c,miR396d,miR396g,miR396h在1.5、3、6 h呈下降表达,在12、24 h呈不同程度上升表达;miR396a、miR396e和miR396f在高温胁迫下上升表达10倍以上,其中miR396f上升100倍以上。Os GRF家族随高温胁迫呈不规律的上升或下降表达,其中Os GRF2随着胁迫时间增加持续下降表达至8~10倍。并且Os GRF2与miR396a、miR396e和miR396f的表达呈高的负相关,表明Os GRF2为miR396a、miR396e和miR396f的靶基因。研究结果表明miR396在水稻耐高温方面有关键作用。  相似文献   

9.
高等植物对渗透胁迫的基因表达   总被引:8,自引:0,他引:8  
干旱、低温、盐渍等环境条件严重限制植物的生长和作物的产量。通过分析植物对环境胁迫的基因表达,人们可以利用基因工程手段获得抗逆性强的作物新品种。本文从以下几个方面介绍有关植物对渗透胁迫的基因表达调控及基因工程的研究进展:(1)植物对渗透胁迫的生理生化反应;(2)渗透胁迫下植物LEA基因的表达;(3)水分胁迫下ABA对基因表达的调控;(4)耐渗透胁迫的植物基因工程。  相似文献   

10.
在谷子基因组中鉴定出一个CIPK(Seita.5G145900,命名为SiCIPK19)基因。为揭示SiCIPK19对逆境胁迫的响应,对其基因结构、蛋白特征、功能、进化等性状进行了系统的分析和预测,并用实时定量PCR(RT-qPCR)检测了其在谷子苗期不同逆境及关键生育期干旱胁迫下的表达。结果表明,SiCIPK19基因位于谷子5号染色体,基因组序列长1 353 bp,编码450个氨基酸,基因无可变剪切,且不含内含子。功能域分析和多序列比对发现,SiCIPK19蛋白具有非常保守的序列结构,与其他植物CIPK蛋白也非常相似。RT-qPCR分析表明,SiCIPK19基因被聚乙二醇6000(PEG 6000)、ABA、高盐和低温胁迫强烈诱导。此外,SiCIPK19基因在谷子拔节期、抽穗期和灌浆期干旱条件下参与了对干旱胁迫的响应,推测该基因参与谷子对非生物逆境的应答,尤其在抽穗期和灌浆期干旱胁迫应答中发挥重要作用。本研究结果为进一步分析CIPK基因逆境应答机制,以及利用基因工程方法改善谷子抗逆性和提高产量提供了理论支持。  相似文献   

11.
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

14.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

15.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

16.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

17.
Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.  相似文献   

18.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

19.
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.  相似文献   

20.
Three slow-growing legume trees used for desert reforestation and urban gardening in the Sonoran Desert of Northwestern Mexico and the Southwestern USA were evaluated whether their growth can be promoted by inoculation with plant growth-promoting bacteria (Azospirillum brasilense and Bacillus pumilus), unidentified arbuscular mycorrhizal (AM) fungi (mainly Glomus sp.), and supplementation with common compost under regular screenhouse cultivation common to these trees in nurseries. Mesquite amargo (Prosopis articulata) and yellow palo verde (Parkinsonia microphylla) had different positive responses to several of the parameters tested while blue palo verde (Parkinsonia florida) did not respond. Survival of all tree species was over 80% and survival of mesquite was almost 100% after 10 months of cultivation. Inoculation with growth-promoting microorganisms induced significant effects on the leaf gas exchange of these trees, measured as transpiration and diffusive resistance, when these trees were cultivated without water restrictions.  相似文献   

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