甘蓝型油菜PIN家族基因的鉴定与生物信息学分析

PIN家族基因是一类调控植物生长素极性运输的重要载体元件, PIN基因编码生长素输出蛋白, 介导生长素在植物体的运输, 然而在基因组较复杂的甘蓝型油菜中缺乏系统研究。本研究运用生物信息学方法在甘蓝型油菜全基因组数据库筛选甘蓝型油菜PIN家族基因, 对鉴定出的29个BnPINs基因开展拷贝数变异、分子特征、跨膜结构域、保守基序、染色体定位、系统进化树构建、PIN蛋白二级结构及三级结构预测等研究, 结合高通量转录组测序进行低氮胁迫下的转录水平分析。结果表明, 甘蓝型油菜PIN家族基因拷贝数明显多于拟南芥、甘蓝和白菜所具有的PIN家族基因数量; BnPINs蛋白多属于由碱性氨基酸组成的稳定蛋白, 含有保守的N末端结构域, 二级结构与拟南芥PIN蛋白相似; 系统进化选择能力分析表明, BnPINs基因与甘蓝和白菜PIN家族基因进化关系相近。转录组测序表明, BnPIN1s、BnPIN2s、BnPIN3s基因主要在甘蓝型油菜根部表达且受长期低氮(72 h)诱导, BnPIN6s和BnPIN8s基因主要在地上部表达, 低氮会抑制BnPIN6s表达。本研究结果为进一步研究甘蓝型油菜PIN家族基因生物学功能尤其是在响应低氮胁迫中的功能奠定基础, 为已知大量数据的其他物种家族基因生物信息学研究提供参考。     

芜菁PIN基因家族的鉴定与生物信息学分析

芜菁(Brassica campestris L. ssp. rapifera Matag syn. B. rapa L.)是十字花科芸薹属园艺作物,其下胚轴和主根膨大形成肉质直根。PIN (Pin-formed)是一种植物特异性蛋白,作为生长素的输出载体,介导生长素的极性运输形成生长素不对称分布,从而在植物生长发育过程中起重要作用,然而目前在芜菁中还缺乏对PIN蛋白的系统研究。本研究基于芜菁及其他植物基因组,结合芜菁和普通白菜下胚轴不同发育时期转录组数据,通过生物信息学方法,对芜菁PIN基因家族进行了鉴定,并进行了蛋白结构及基因结构分析、系统发育分析、共线性分析和表达分析。结果表明,芜菁中共有13个BcPIN,数量多于拟南芥和甜菜,但略少于萝卜、胡萝卜和水稻;不同物种间同种类PIN基因数量存在差异;芜菁PIN家族与拟南芥、萝卜PIN家族基因进化关系较近,与水稻PIN家族基因关系较远,分布在4条染色体上,包括7个共线性基因对;BcPINs启动子含有多种顺式作用元件,受多种信号调控,但不同BcPINs的顺式元件种类存在差异;BcPINs的氨基酸个数在270～661之间,分子量在29.81...     

番茄PIN2基因的生物信息学分析

PIN基因家族是调控生长素运输的重要输出载体。拟南芥PIN2介导的生长素极性运输在生长素不对称分布在根的向重力性反应中起着关键性调控作用(潘建伟等,2010)。植物根系的重力性决定着根系空间生长的趋势,对植物养分的吸收有着重要的影响。本研究选择功能已知的拟南芥PIN2基因为参考序列,对番茄PIN2基因开展了蛋白组分和理化性质,系统进化分析,蛋白结构预测,跨膜结构分析等生物信息学研究,为番茄PIN2基因的生物学功能及分子机理提供理论基础。     

水稻和拟南芥NBS-LRR基因家族同义密码子使用偏好的比较

应用软件CodonW,对全基因组进行分析,鉴定出水稻和拟南芥NBS-LRR基因家族的最优密码子分别为25和16种。NBS-LRR基因家族与其全基因组的最优密码子一致,但两个物种间彼此完全不一致,密码子使用上发生偏向的程度也不尽相同。说明NBS-LRR基因家族的密码子使用偏好受物种自身的影响很大。同时,同一物种内基因家族对密码子的     

大豆SPL基因家族生物信息学分析

SQUAMOSA启动子结合蛋白样(SPL)转录因子广泛存在于植物中,主要参与植物生长、发育以及多种生理生化过程。为明确大豆SPL基因家族在染色体上的分布、保守结构域、亚族种类、进化关系等,采用生物信息学方法对大豆SPL家族基因进行分析。本研究从大豆基因组数据库中筛选得到43个SPL基因家族成员,系统发育树分析得到5个亚群。保守结构同源性分析发现,SPL基因家族都含有SBP-box的锌指结构和核定位信号。染色体定位发现除14号染色体没有SPL分布外,其他染色体均有不同数量的SPL基因分布。基因加倍、扩张分析表明,大豆SPL基因家族成员之间不存在串联重复,但是存在36对片段重复,表明部分大豆SPL基因可能是由基因重复产生;大豆与拟南芥SPL基因家族之间有29个基因之间存在共线性关系,表明大豆与拟南芥SPL基因家族之间具有较高同源性。本研究对SPL基因家族的进化分析,将有助于理解大豆SPL基因的结构、功能及进化关系,为深入研究大豆SPL基因的功能提供有利的理论依据。     

水稻NRL基因家族的全基因组鉴定与生物信息学分析

NRL (NPH3/RPT2-Like)基因家族是植物中特异存在的基因家族,根据拟南芥NRL基因家族中参与植物向光性响应的NPH3 (NONPHOTOTROPIC HYPOCOTYL 3)和RPT2 (ROOT PHOTOTROPISM 2)命名.本研究利用生物信息学方法鉴定到27个水稻NRL基因,分布在除10号染色体外的染色体上,同时基因复制分析结果表明,全基因复制或片段复制比串联复制在水稻NRL基因家族扩张中起更大的作用.利用单、双子叶植物的7个物种进行系统进化关系分析,将192个NRL基因家族成员分为6个不同的组.水稻NRL家族的结构特征分析显示,多数成员含有NRL基因家族的特征结构域,而基于RNA-Seq和微阵列数据的表达分析结果表明,水稻NRL家族基因在多个组织表达,同时部分基因在叶片、花序和花药中高表达.本研究对水稻NRL基因家族进行鉴定和分析,为进一步研究水稻NRL基因家族的功能提供了一定的参考和依据.     

枣OVATE基因家族的鉴定与生物信息学分析

OVATE基因家族编码一类广泛存在于植物体内的转录抑制因子,但枣中OVATE基因家族研究未见报道。本研究基于枣全基因组数据鉴定到枣OVATE基因家族15个基因,并对其进行生物信息学分析,发现15个基因非均匀地分布在8条染色体上,各基因长度相差较大,除了ZjOFP3以外,均不含有内含子结构。各基因共有motif 1保守基序,除ZjOFP15以外都含有motif 1、motif 2和motif 3保守基序且顺序相同。系统进化研究发现枣、桃和苹果等6个物种的OVATE基因家族的119条蛋白序列可以分为4个类群,而枣OVATE基因家族分布在各个类群中,进化过程中相对保守。枣OVATE蛋白分别定位细胞外、线粒体、质膜及细胞核上,反映出OVATE基因家族功能的多样性。此外,除了ZjOFP3、ZjOFP9和ZjOFP15以外,其余皆有着相似的三级结构。顺式作用元件预测发现枣OVATE基因家族与光响应、逆境胁迫、激素诱导、生长发育有关。本研究可为枣OVATE基因家族进一步研究提供参考。     

黄皮转录组密码子使用偏好性分析

为全面了解黄皮(Clausena lansium)表达基因的密码子使用特点,以转录组测序获得的12 696条编码蛋白基因序列为数据来源,利用CodonW 14.4软件对其密码子碱基组成以及有效密码子数(effective number of codon, ENC)、同义密码子相对使用频率(relative frequency of synonymous codon, RFSC)等密码子使用参数进行计算和统计,发现黄皮表达基因密码子的平均GC含量为0.448,同义密码子第3位核苷酸的平均GC含量(GC3S)为0.400。表达基因整体的ENC取值为56.5,其中绝大部分的ENC值大于35,说明黄皮表达基因密码子使用偏好性程度整体水平较低。通过高频密码子分析法确定了GCU、AGA、AAU、GAU、AUU、UUU、UCU、CAU、CUU、UUG和GUU 11个高频密码子。将黄皮的密码子使用频率与人、小鼠、果蝇、酵母、大肠杆菌5种模式生物以及拟南芥、水稻、葡萄、草莓4种不同类型植物进行比较,发现其与果蝇和大肠杆菌存在较大差异,而与拟南芥和葡萄基本一致。以上研究结果对黄皮基因合适表达系统的选择以及外源基因在黄皮中的高效表达具有重要指导意义。     

毛竹WUSCHEL-related homeobox(WOX)基因家族鉴定及表达分析

WOX基因家族是植物特有的转录因子家族,在干细胞分裂和分化的维持中发挥着关键作用。虽然在模式植物拟南芥和水稻中,WOX基因家族的功能已有深入的研究,但是毛竹Ph WOX基因家族的表达模式和功能仍属未知。本研究系统地分析毛竹Ph WOX基因家族,首先在毛竹基因组数据库进行检索获取毛竹WOX基因家族,鉴定出毛竹基因组编码5个Ph WOX基因。通过遗传进化和基因结构分析,毛竹Ph WOX基因家族分为现代/WUS进化分支和古老进化分支。有趣的是毛竹Ph WOX基因家族在根、茎、叶和笋中广泛表达,并且在竹笋的发育过程中动态表达。本研究首次分析毛竹Ph WOX基因家族的功能,揭示了毛竹Ph WOX基因家族具有独特的进化模式和多样的表达模式,为后续探索毛竹发育的分子机制奠定基础。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Variation in forage grasses as hosts of the root-knot nematode Meloidogyne naasi (Franklin) and selection for resistance in ryegrass

Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Current and future strategies in breeding lentil for resistance to biotic and abiotic stresses

Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...