香蕉14-3-3蛋白基因Ma-14-3-3d的克隆及序列分析(英文)

[Objective] The aim of the study is to clone and analyze the gene encoding 14-3-3 protein from banana. [Method] Combined with PCR amplification, RACE (rapid amplification of cDNA ends) technique was employed to clone 14-3-3 gene from banana; then the amplified sequence was sequenced and homologically analyzed. [Result] A new cDNA homologous with 14-3-3 protein genes were obtained by RT-PCR and RACE ( rapid amplification of cDNA ends ) approaches. The full length of this cDNA was 866 bp encoding 197 amino acids. Alignment of deduced amino acid sequence with those from other plants revealed that the cDNA shared high homology with 14-3-3 protein genes from other plants, and was designated as Musa acuminata 14-3-3 gene (Ma-14-3-3d). Phylogenetic analysis reveals that Ma-14-3-3d has closer genetic relationship with those from monocotyledon species than those from other species. [Conclusion] Ma-14-3-3d belongs to the same lineage of 14-3-3 from monocotyledon.     

History of atmospheric lead deposition since 12,370 (14)C yr BP from a peat bog, jura mountains, switzerland

A continuous record of atmospheric lead since 12,370 carbon-14 years before the present (14C yr BP) is preserved in a Swiss peat bog. Enhanced fluxes caused by climate changes reached their maxima 10, 590 (14)C yr BP (Younger Dryas) and 8230 (14)C yr BP. Soil erosion caused by forest clearing and agricultural tillage increased lead deposition after 5320 (14)C yr BP. Increasing lead/scandium and decreasing lead-206/lead-207 beginning 3000 (14)C yr BP indicate the beginning of lead pollution from mining and smelting, and anthropogenic sources have dominated lead emissions ever since. The greatest lead flux (15.7 milligrams per square meter per year in A.D. 1979) was 1570 times the natural, background value (0.01 milligram per square meter per year from 8030 to 5320 (14)C yr BP).     

水分胁迫对苹果组培苗14C-光合产物运输和分配的影响

通过调节PEG（6000）溶液的渗透势模拟不同程度水分胁迫条件，研究其对“红富士”苹果组培苗^14C-光合产物运输和分配的影响。结果表明，1）水分胁迫使饲喂叶中^14C-光合产物输出百分率显著下降：试验结束时对照^14C-光合产物输出率为轻度胁迫（PEG渗透势为-0．75MPa）的1．42倍、中度胁迫（PEG渗透势为-1．5MPa）的3．41倍、重度胁迫（PEG渗透势为-2．5MPa）的10．18倍；且轻度和中度胁迫使叶片^14C-光合产物的输出在24h内分别达到48h的94．22％和93．95％，显著高于对照（55．65％），在时间上表现得更为集中。2）正常水分条件下，苹果叶片输出^14C-光合产物的89．43％运往地上部，仅10．57％运往根部，重度胁迫则使高达64．78％的^14C-光合产物运往地下部；地上部、特别是茎尖对光合产物的竞争能力（^14C-分配系数，K）由对照的3．42显著下降至不同程度水分胁迫处理后的1．30～0．48，其对光合产物的竞争能力显著下降；而地下部、特别是细根^14C-分配系数由对照的0．16增加至0．82～1．26．其获取光合产物的能力显著增强。     

Rabbit hemoglobin biosynthesis: use of human hemoglobin chains to study molecule completion

A cell-free protein-synthesizing system made from rabbit reticulocytes was used to incorporate (14)C-amino acids into hemoglobin. Electrophoretic analyses of the soluble products of this cell-free system revealed a fraction containing rabbit (14)C-alpha chains in addition to the rabbit (14)C-hemoglobin. The addition of isolated human hemoglobin beta chains to this system during active synthesis inhibited the release of newly synthesized rabbit (14)C-beta chains into solution from the ribosome fraction. This inhibition was possibly a result of hybrid hemoglobin formation between rabbit alpha and human beta chains. A model of hemoglobin construction in which soluble alpha chains are intermediates is suggested. These alpha chains may aid in the release of beta chains from the polyribosomes during the completion of the hemoglobin molecule.     

Changes in atmospheric carbon-14 attributed to a variable sun

The (14)C production rate in the upper atmosphere changes with time because the galactic cosmic-ray flux responsible for (14)C production is modulated by the changes in solar wind magnetic properties. The resulting changes in the atmospheric (14)C level are recorded in tree rings and are used to calculate past (14)C production rates from a carbon reservoir model that describes terrestrial carbon exchange between the atmosphere, ocean, and biosphere. These past (14)C production rate changes are compared with (14)C production rates determined from 20th-century neutron flux measurements, and a theory relating (14)C production and solar variability, as given by geomagnetic Aa indices and sunspot numbers, is developed. This theory takes into account long-term solar changes that were previously neglected. The 860-year (14)C record indicates three episodes when sunspots apparently were absent: A.D. 1654 to 1714 (Maunder minimum), 1416 to 1534 (Sp?rer minimum), and 1282 to 1342 (Wolf minimum). A less precisely defined minimum occurred near A.D. 1040. The part of this record after A.D. 1645 correlates well with the basic features of the historical record of sunspot numbers. The magnitude of the calculated (14)C production rates points to a further increase in cosmic-ray flux when sunspots are absent. This flux was greatest during the Sp?rer minimum. A record of approximate sunspot numbers and Aa indices for the current millennium is also presented.     

松材线虫和拟松材线虫14-3-3蛋白基因全长cDNA克隆与分析

[目的]对松材线虫和拟松材线虫的14-3-3蛋白基因进行全长cDNA克隆,并进行序列分析。[方法]根据GenBank数据库中14-3-3蛋白EST序列BXC56（登录号为FG589472）、BMCl20（登录号为FG589351）,采用RACE技术获取松材线虫和拟松材线虫14-3-3蛋白的全长cDNA克隆Bxl4-3-3a和Bml4-3-3a,并对克隆片段序列进行分析。[结果]Bx14-3-3a全长1039bp,包含一个756bp的开放阅读框,编码蛋白含有251个氨基酸残基,包含2个14-3-3蛋白标签,编码蛋白分子量为61．43kD,等电点为4．88。Bx14-3-3a基因组结构中包含4个外显子和3个内舍子序列。Bm14-3-3a全长992bp。有与Bx14-3-3a编码完全相同的氨基酸序列。序列比对结果表明,14-3-3在真核生物间高度保守,Bx14-3-3A和Bm14-3-3A蛋白在系统进化上与线形动物门（Nematomorpha）的物种近缘关系较近,与植物线虫南方根结线虫（Meloidogyneincognita）系统发育关系上最为亲近。[结论]Bx14-3-3a和Bm14-3-3a的成功克隆,为进一步研究其功能及其调控因子对形态、致病力、繁殖力和环境适应性等方面的分子调控机制奠定了重要基础。     

香蕉14-3-3蛋白基因Ma-14-3-3d的克隆及序列分析

[目的]克隆分析香蕉中14-3-3蛋白编码基因。[方法]采用PCR与RACE技术相结合的方法克隆香蕉14-3-3基因,并进行CDNA测序及同源性分析。[结果]所克隆cDNA全长866 bp,编码197个氨基酸残基,具有植物14-3-3蛋白基因的特征结构域,并与其他植物来源的14-3-3蛋白具有很高的序列相似性,将其命名为Ma-14-3-3d(Musa acuminate14-3-3gene)。[结论]Ma-14-3-3d蛋白与来源于单子叶植物的14-3-3蛋白位于同一进化枝上。     

Carbon-14 in methane sources and in atmospheric methane: the contribution from fossil carbon

Measurements of carbon-14 in small samples of methane from major biogenic sources, from biomass burning, and in "clean air" samples from both the Northern and Southern hemispheres reveal that methane from ruminants contains contemporary carbon, whereas that from wetlands, pat bogs, rice fields, and tundra is somewhat, depleted in carbon-14. Atmospheric (14)GH(4) seems to have increased from 1986 to 1987, and levels at the end of 1987 were 123.3 +/- 0.8 percent modern carbon (pMC) in the Northern Hemisphere and 120.0 +/- 0.7 pMC in the Southern Hemisphere. Model calculations of source partitioning based on the carbon-14 data, CH(4) concentrations, and delta(13)C in CH(4) indicate that 21 +/- 3% of atmospheric CH(4) was derived from fossil carbon at the end of 1987. The data also indicate that pressurized water reactors are an increasingly important source of (14)CH(4).     

Ventilation of the glacial deep Pacific Ocean

Measurements of the age difference between coexisting benthic and planktic foraminifera from western equatorial Pacific deep-sea cores suggest that during peak glacial time the radiocarbon age of water at 2-kilometers depth was no greater than that of today. These results make unlikely suggestions that a slowdown in deep-ocean ventilation was responsible for a sizable fraction of the increase of the ratio of carbon-14 (14C) to carbon in the atmosphere and surface ocean during glacial time. Comparison of 14C ages for coexisting wood and planktic foraminifera from the same site suggests that the atmosphere to surface ocean 14C to C ratio difference was not substantially different from today's.     

温州蜜柑晚秋光合产物分配与运转的研究

晚秋给两年生未结果温州蜜柑盆栽苗饲喂~(14)CO_2,随后测定不同物候期柑桔苗各器宫的~(14)C同化物的放射性总后度、比活度、~(14)C可溶性成分及氨基酸相对含量.结果表明,在次年新器官生长前,~(14)C同化物主要由叶片向根部运转,~(14)C总活度在根系中的分配达50％以上.从标记后半个月到休眠期,所有器官包括秋叶的放射性比活度增加,唯有春叶比活度明显降低,秋叶却能从春叶中获得养价补充.次年5～11月,新梢生长动用约1/5的14C同化物,同时地上部其他器官的~(14)C分配减少约8.57％,根部减少5.45％,表明新梢生长所需养分主要来自地上部.可溶性~(14)C随年周期进程不断减少.可溶性成分中氨基酸相对含量以新器官和生长期间的器官为高.韧皮部的放射性比活度明显高于木质部,氨基酸含量也以前者为高.     

Variation in atmospheric carbon-14 activity relative to a sunspot-auroral solar index

Radiocarbon activity was negatively correlated (P相似文献   

Atmospheric radiocarbon calibration to 45,000 yr B.P.: late glacial fluctuations and cosmogenic isotope production

More than 250 carbon-14 accelerator mass spectrometry dates of terrestrial macrofossils from annually laminated sediments from Lake Suigetsu (Japan) provide a first atmospheric calibration for almost the total range of the radiocarbon method (45,000 years before the present). The results confirm the (recently revised) floating German pine chronology and are consistent with data from European and marine varved sediments, and combined uranium-thorium and carbon-14 dating of corals up to the Last Glacial Maximum. The data during the Glacial show large fluctuations in the atmospheric carbon-14 content, related to changes in global environment and in cosmogenic isotope production.     

二穗短柄草钙依赖型蛋白激酶基因 BdCDPK14克隆及表达分析

[目的]克隆分析二穗短柄草钙依赖型蛋白激酶(CDPK)基因BdCDPK14,并检测其在干旱胁迫下的表达量,为揭示钙依赖型蛋白激酶的抗旱调控机制打下基础.[方法]根据NCBI检索结果设计特异引物,以二穗短柄草cDNA为模板,采用PCR扩增二穗短柄草CDPK基因家族成员BdCDPK14,利用在线分析软件对BdCDPK14基因编码蛋白进行生物信息学分析,并采用RT-PCR检测PEG-6000干旱胁迫下的BdCDPK14基因表达量.[结果]从二穗短柄草叶片中克隆获得的BdCDPK14基因(GenBank登录号XM_003564390)片段长度1750 bp,其开放阅读框(ORF)1545 bp,编码514个氨基酸,其编码蛋白分子量56.78 kD,理论等电点5.45,脂肪指数78.21,不稳定指数38.66,属于稳定蛋白.BdCDPK14蛋白与小麦TaCPK13蛋白(ABY59018)的亲缘关系最近,含有4个EF-hands结构、蛋白酪氨酸激酶结构域、脂多糖激酶家族、ATP结合区域、丝氨酸/苏氨酸蛋白激酶激活区和预测跨膜区等结构域,主要由无规卷曲和α-螺旋构成,位于叶绿体和细胞质膜上.在PEG-6000干旱胁迫下,BdCDPK14基因在胁迫3 h内的相对表达量无明显变化,胁迫6 h后相对表达量开始升高,至胁迫12 h时的相对表达量最高.[结论]克隆获得的BdCDPK14基因为二穗短柄草CDPK基因家族成员之一,参与其抗干旱胁迫反应,可作为候选基因用于二穗短柄草抗旱机制研究.     

PtWRKY14 基因转化烟草及对 TMV 的抗性影响研究

PtWRKY14 是从毛白杨中获得的WRKY 基因,为研究PtWRKY14 基因对植物抗病性的影响,构建了毛 白杨PtWRKY14 基因的植物表达载体pBI121-W14,通过农杆菌介导的叶盘转化法转化烟草,PCR 与Southern 杂交 进行转基因烟草鉴定。对获得的转基因烟草植株进行烟草花叶病毒(Tobacco mosaic virus,TMV）的接种试验,结果表 明PtWRKY14 基因的转化使烟草对TMV 的抗性增强。荧光定量PCR 检测结果表明,TMV 接种后,转基因烟草中 PtWRKY14 的表达量显著上调,同时转基因烟草中超氧化物歧化酶(Superoxide Dismutase,SOD）、过氧化物酶(Peroxidase,POD）、过氧化氢酶(Catalase,CAT）的表达量均高于对照组。因此,PtWRKY14 可能通过上调SOD、POD、 CAT 的表达从而增强植物抗病性。     

小麦灌浆期光合产物运转的示踪动力学研究

应用活体测量技术和示踪动力学原理，建立了双增剂对小麦灌浆期光合产物输配影响的调节模型，并实测了双增剂处理的剑叶光合产物输出系数Ｋ＿Ｌ和输导系统光合产物运转系数Ｋ＿ｓ分别为０．０６和０．２４，高于对照２０．００％和７１．４２％；３６ｈ内穗光合产物积累率为７０．８９％，高于对照９．１１％；光合产物从叶输到穗所经历的时间比对照提前１ｈ。结果表明，双增剂加快了光合产物向籽粒运输的总速率和加强了光合产物向籽粒方向的分配。     

A Large Drop in Atmospheric 14C/12C and Reduced Melting in the Younger Dryas, Documented with 230Th Ages of Corals

Paired carbon-14 ((14)C) and thorium-230((230)Th) ages were determined on fossil corals from the Huon Peninsula, Papua New Guinea. The ages were used to calibrate part of the (14)C time scale and to estimate rates of sea-level rise during the last deglaciation. An abrupt offset between the (14)C and (230)Th ages suggests that the atmospheric (14)C/(12)C ratio dropped by 15 percent during the latter part of and after the Younger Dryas (YD). This prominent drop coincides with greatly reduced rates of sea-level rise. Reduction of melting because of cooler conditions during the YD may have caused an increase in the rate of ocean ventilation, which caused the atmospheric (14)C/(12)C ratio to fall. The record of sea-level rise also shows that globally averaged rates of melting were relatively high at the beginning of the YD. Thus, these measurements satisfy one of the conditions required by the hypothesis that the diversion of meltwater from the Mississippi to the St. Lawrence River triggered the YD event.     

Isolation and Characterization of NBS-LRR Class Resistance Homologous Gene from Wheat

One resistance gene analog fragment named RGA-CIN14 was isolated from TcLr19 wheat,which contains kinase-2,kinase-3a,and the GLPL motif of the NBS-spanning region,using degenerated primers according to the nucleotide binding site (NBS) conserved domain.Based on the RGA-CIN14,a full-length cDNA,CIN14,which was 2 987 bp encoding 880 amino acids,was obtained by using the method of the rapid amplification cDNA ends (RACE).Bioinformatics analysis showed that the deduced amino acids of CIN14 protein consisted of a NB-ARC conserved domain and many leucine-rich repeats (LRR) domains.The phylogenetic tree analysis indicated a considerable identity of the protein encoded by CIN14 with that of wheat leaf rust resistance gene Lr1,but a lower similarity with Lr21.The expression profile of the CIN14 gene detected by semi-quantitative RT-PCR showed that the CIN14 gene was not induced by Puccinia triticina and it was a constitutive gene with low abundance in the wheat leaf tissue.The resistance homology sequence was successfully obtained,which provides the shortcut for cloning of the resistance gene in TcLrl9 wheat.     

Isolation and characterization of a novel protein (X-ORF product) from SIV and HIV-2

A protein designated p14 was purified from a simian immunodeficiency virus (SIVMne) and was shown by amino acid sequence analysis to be nearly identical to the predicted translational product of a unique open reading frame (X-ORF) in the nucleotide sequences of SIVmac and human immunodeficiency virus type 2 (HIV-2). Thus the X-ORF is proven to be a new retroviral gene. The p14 is present in SIVMne in molar amounts equivalent to those of the gag proteins. This is the first example of a retrovirus that contains a substantial quantity of a viral protein that is not a product of the gag, pro, pol, or env genes. SIV p14 and its homolog in HIV-2 may function as nucleic acid binding proteins since purified p14 binds to single-stranded nucleic acids in vitro. Antisera to the purified protein detected p14 in SIVMne, SIVmac, and a homologous protein (16 kilodaltons) in HIV-2 but did not react with HIV-1. Diagnostic procedures based on this novel protein will distinguish between HIV-1 and HIV-2.     

Preferential synthesis of ferritin and albumin by different populations of liver polysomes

Free polysomes and a mixture of free and membrane-attached polysomes were isolated separately from rat liver, and each was added to a cell-free, protein-synthesizing system. The free polysomes showed a greater capacity than the mixed polysome population for incorporation of (14)C-leucine into ferritin, whereas the reverse was true for (14)C-leucine incorporation into albumin.     

Lysergic acid diethylamide: role in conversion of plasma tryptophan to brain serotonin (5-hydroxytryptamine)

Injections of D-lysergic acid diethylamide decrease the turnover rate of 5-hydroxytryptamine of rat brain, as measured from the conversion of (14)C-tryptophan into (14)C-5-hydroxytryptamine. The 2-bromolysergic acid diethylamide given in doses fivefold greater than those of lysergic acid diethylamide fails to change the rate of (14)C-tryptophan conversion into (14)C-5-hydroxytryptamine. The effect of D-lysergic acid diethylamide is discussed with regard to its action on brain serotonergic neurons and its psychotomimetic effects.