茶树NAC转录因子基因CsNAC79和CsNAC9鉴定及其对非生物胁迫的响应

【目的】鉴定茶树NAC转录因子基因CsNAC79和CsNAC9,并分析它们在干旱、盐、高温、低温、外施ABA和外施GA₃胁迫下的表达模式,为进一步解析CsNAC79和CsNAC9转录因子的生物学功能提供参考。【方法】以茶树‘龙井43’为材料,用RT-PCR扩增NAC转录因子家族基因CsNAC79和CsNAC9,并进行生物信息学分析;用qRT-PCR检测CsNAC79和CsNAC9在茶树6种非生物胁迫下的相对表达量。【结果】(1)CsNAC79和CsNAC9分别编码409个和282个氨基酸,且分别在15—150氨基酸位点、11—134氨基酸位点含有NAC家族成员典型的NAM保守结构域。(2)CsNAC79蛋白与中华猕猴桃、柿、洋蓟亲缘关系较近,CsNAC9蛋白与桃、荔枝、榴莲亲缘关系较近;2个NAC转录因子均是亲水性蛋白,皆不含信号肽和跨膜结构;CsNAC79和CsNAC9的启动子区域都含有非生物胁迫响应元件;蛋白质空间结构分析显示,CsNAC79和CsNAC9蛋白主要是由不规则卷曲和α-螺旋组成。(3)表达分析表明：CsNAC79和CsNAC9基因在6种不同非生物...     

茶树品种‘安吉白茶’ CsDREB-A4 b基因的克隆及其对非生物胁迫的响应

采用RT-PCR方法从茶树﹝Camellia sinensis ( Linn.) O. Ktze.﹞品种‘安吉白茶’(‘Anjibaicha’)叶片的cDNA中克隆得到1个编码DREB转录因子的基因,命名为CsDREB-A4b。序列分析结果显示,CsDREB-A4b基因包含长度为873 bp的开放阅读框,编码290个氨基酸,具有保守的AP2结构域。与拟南芥﹝Arabidopsis thaliana ( Linn.) Heynh.﹞AP2/ERF家族转录因子进行同源进化分析,CsDREB-A4b转录因子属于DREB亚族中的A4组。多重比对结果显示：CsDREB-A4b转录因子与蓖麻(Ricinus communis Linn.)等植物的DREB类转录因子保守结构域氨基酸序列的相似性较高。 CsDREB-A4b转录因子为亲水性蛋白,理论相对分子质量为31938.5,理论等电点为pI 5.91,总平均疏水性为-0.603,碱性、酸性、芳香族和脂肪族氨基酸的比例分别为12%、12%、7%和15%。在高温(38℃)胁迫处理前期,CsDREB-A4b基因的相对表达量显著高于胁迫处理前;在低温(4℃)胁迫处理下,CsDREB-A4b基因的相对表达量呈显著升高的趋势;在盐(200 mmol·L-1 NaCl)和干旱(200 g·L-1 PEG)胁迫处理下,CsDREB-A4b基因的相对表达量呈先降低后显著升高的趋势。表明CsDREB-A4b基因参与‘安吉白茶’非生物胁迫的响应过程,且在不同胁迫条件下具有表达差异性。     

茶树谷丙转氨酶基因的克隆及其表达分析

该研究基于茶树的转录组数据,采用RT PCR方法从茶树‘黄金芽’cDNA中克隆获得茶树谷丙转氨酶基因（CsAlaAT）,利用荧光定量PCR方法,对CsAlaAT在茶树材料‘迎霜’和‘黄金芽’不同组织、温度胁迫与激素处理的表达进行分析。结果显示：CsAlaAT基因开放阅读框长度为1 662 bp,编码553个氨基酸,含有天冬氨酸转氨酶家族（Aspartate aminotransferase family）典型的AAT like保守结构域。多序列比对显示,该序列与多个相关物种的序列一致性达78.83%,与磷酸吡哆醛（PLP）结合的10个氨基酸残基以及第358位赖氨酸催化位点在物种间高度保守。茶树CsAlaAT蛋白属亲水性蛋白,相对分子质量为60 877.5 D,等电点为6.11,碱性、酸性、脂肪族和芳香族氨基酸比例分别为12%、11%、22%和8%,无序化特征不明显,与大麦HvAlaAT具有相似的三维结构。实时定量PCR分析表明,CsAlaAT在茶树‘迎霜’和‘黄金芽’中的表达均具有组织特异性,且均在根部的表达量最高;CsAlaAT响应高温（38 ℃）和低温（4 ℃）胁迫的表达上调;外源施用脱落酸（ABA）和赤霉素（GA）能够抑制茶树中CsAlaAT基因的表达。     

低温胁迫对2个茶树品种叶片叶绿素荧光特性的影响

以茶树〔Camellia sinensis ( Linn.) O. Ktze.〕品种‘黄金芽’(‘Huangjinya’)和‘迎霜’(‘Yingshuang’)为实验材料,研究了4℃低温胁迫1、2、4和6d对茶树叶片叶绿素荧光特性的影响。结果表明：4℃低温胁迫条件下2个茶树品种叶片的PSⅡ最大光化学效率( Fv/Fm )、PSⅡ潜在活性( Fv/F0)和表观光合电子传递速率( ETR)均显著低于各自的对照(25℃),且总体上随胁迫时间延长逐渐下降;‘黄金芽’叶片的光化学淬灭系数(qP)随低温胁迫时间延长持续下降且低于其对照,而‘迎霜’叶片的qP较其对照的变幅较小,且2个品种的qP总体上与各自的对照无显著差异;随低温胁迫时间延长,2个品种叶片的非光化学淬灭系数( NPQ)均先升高后降低,并在胁迫2 d时达到最高,且总体上高于各自的对照;而2个品种叶片的光合功能相对限制值( LPFD )均随低温胁迫时间延长而增大,且大多高于各自的对照。与各自的对照相比,低温胁迫条件下‘迎霜’叶片的各项叶绿素荧光参数的变幅总体上低于‘黄金芽’。研究结果显示：低温胁迫可直接损伤茶树叶片的PSⅡ反应中心,致使过剩的激发能大量积累于PSⅡ反应中心,最终导致茶树光合作用能力减弱。根据叶绿素荧光参数的比较结果,可以初步判定品种‘迎霜’的耐寒性优于品种‘黄金芽’。     

茶树BES1转录因子全基因组鉴定与分析

植物特异性转录因子(BRI1-EMS-SUPPRESSOR1,BES1)家族参与调节油菜素内酯(brassinosteroids,BR)信号通路,在植物生长和应对非生物胁迫的反应中发挥重要作用。该研究利用生物信息学方法对茶树BES1转录因子家族进行鉴定,分析茶树CsBES1基因在8个茶树组织中的表达模式,并对CsBES1转录因子家族在低温、干旱及ABA激素处理下的表达进行分析,以揭示茶树CsBES1转录因子家族的功能及其对环境胁迫的响应。结果显示:(1)从茶树全基因组中鉴定获得10个茶树BES1转录因子家族成员,均具有完整的BES1_N结构域;根据系统进化关系将10个CsBES1转录因子家族分成3组,分别包含2个、3个和5个成员;该家族成员每个基因含有2～11个外显子。(2)组织表达模式分析显示,茶树BES1转录因子家族在生长活跃的茶树嫩梢和成熟叶中表达量较高,不同成员之间表达存在差异性。(3)上游启动子区域分析发现大量与植物激素和非生物胁迫响应相关的顺式作用元件。(4)荧光定量检测发现,BES1基因在茶树不同胁迫处理下的表达模式不同,在低温和脱落酸处理下,CsBES1-1、CsBES1-7、CsBES1-8和CsBES1-9基因的表达量显著提高,而在干旱处理下,CsBES1-2、CsBES1-4、CsBES1-5、CsBES1-6、CsBES1-7、CsBES1-8和CsBES1-9基因的表达量显著提高。     

甘蓝型油菜扩展蛋白家族的全基因组鉴定及其对缺硼胁迫响应的差异分析

以甘蓝型油菜(Brassica napus L.)硼高效品种‘青油10号’和硼低效品种‘Westar 10’为研究对象,采用生物信息学分析、转录组测序和实时荧光定量PCR技术,鉴定其基因组中扩展蛋白的家族成员,并对该基因家族响应缺硼胁迫的表达差异进行分析。结果显示,甘蓝型油菜基因组中包含109个扩展蛋白,可分为4个亚家族,包括:79个扩展蛋白A(BnaEXPAs)、21个扩展蛋白B(BnaEXPBs)、5个类扩展蛋白A(BnaEXLAs)和4个类扩展蛋白B(BnaEXLBs)。同一亚家族中的扩展蛋白具有相对保守的基因结构和蛋白质基序组成。这些扩展蛋白基因分布在19条染色体上,其中10个位于硼高效QTL区间内。转录组测序分析结果表明,缺硼胁迫时‘青油10号’的根、幼叶和老叶中分别有40、18和30个扩展蛋白基因显著上调或下调表达;而‘Westar10’中分别有27、24和41个扩展蛋白基因显著上调或下调表达。其中‘青油10号’根中的BnaC04.EXPA6a,幼叶中的BnaA09.EXPA5以及老叶中的BnaA09.EXPA16、BnaC04.EXPA3、BnaCnn.EXPA5b和BnaA03.EXPA8基因的表达水平均显著高于‘Westar10’。研究结果说明甘蓝型油菜基因组中扩展蛋白基因家族数量庞大,其中高、低效品种间和不同硼水平中差异表达的扩展蛋白可能在甘蓝型油菜低硼适应性中发挥重要作用。     

甘蓝型油菜扩展蛋白家族的全基因组鉴定及其对缺硼胁迫响应的差异分析（英文）

以甘蓝型油菜(Brassica napus L.)硼高效品种‘青油10号’和硼低效品种‘Westar 10’为研究对象,采用生物信息学分析、转录组测序和实时荧光定量PCR技术,鉴定其基因组中扩展蛋白的家族成员,并对该基因家族响应缺硼胁迫的表达差异进行分析。结果显示,甘蓝型油菜基因组中包含109个扩展蛋白,可分为4个亚家族,包括:79个扩展蛋白A(Bna EXPAs)、21个扩展蛋白B(Bna EXPBs)、5个类扩展蛋白A(Bna EXLAs)和4个类扩展蛋白B(Bna EXLBs)。同一亚家族中的扩展蛋白具有相对保守的基因结构和蛋白质基序组成。这些扩展蛋白基因分布在19条染色体上,其中10个位于硼高效QTL区间内。转录组测序分析结果表明,缺硼胁迫时‘青油10号’的根、幼叶和老叶中分别有40、18和30个扩展蛋白基因显著上调或下调表达;而‘Westar10’中分别有27、24和41个扩展蛋白基因显著上调或下调表达。其中‘青油10号’根中的Bna C04.EXPA6a,幼叶中的Bna A09.EXPA5以及老叶中的Bna A09.EXPA16、Bna C04.EXPA3、Bna Cnn.EXPA5b和Bna A03.EXPA8基因的表达水平均显著高于‘Westar10’。研究结果说明甘蓝型油菜基因组中扩展蛋白基因家族数量庞大,其中高、低效品种间和不同硼水平中差异表达的扩展蛋白可能在甘蓝型油菜低硼适应性中发挥重要作用。     

梭梭NAC转录因子HaNA C3～4的克隆及表达分析

本研究从梭梭中克隆了2条NAC基因,分别命名为序列Ha NAC3(KU534095)和Ha NAC4(KU534-096)。序列分析显示Ha NAC3基因编码一条242个氨基酸的多肽,Ha NAC4基因编码一条287个氨基酸的多肽,并且编码的蛋白都为亲水性蛋白。经过同源性比对分析发现2条序列都含有典型的NAC结构域,属于NAC转录因子家族。组织特异性表达分析结果显示Ha NAC3序列在梭梭根部有较高强度的表达;Ha NAC4在梭梭种子中表达量较高。干旱胁迫下,Ha NAC3和Ha NAC4呈现出不同的表达方式,本研究有助于为进一步分析梭梭NAC家族基因功能提供帮助。     

多年生黑麦草温度胁迫差异表达转录因子的比较转录组分析

多年生黑麦草是禾本科冷季型草种,温度胁迫严重影响其分布和产量。转录因子调控基因表达在植物响应逆境胁迫中发挥重要作用。该研究以多年生黑麦草品种雅晴为材料,采用高通量RNA-seq技术,对热(40℃)、冷冻(-10℃)和对照(22℃)处理的样本进行转录因子应答分析,以探索多年生黑麦草转录因子对温度胁迫的响应规律,并筛选抗逆转录因子候选基因。结果显示:(1)共鉴定了694个转录因子unigenes,分属于AP2/ERF、GTF、HSF、MYB、NAC、WRKY、bHLH和bZIP等32个家族。(2)在热和冷冻胁迫下,ERF(AP2/ERF)、MYB、NAC和bZIP家族基因均以上调为主,而WRKY家族则多数下调。HSF、GTF和DREB(AP2/ERF)家族成员大多数受热诱导上调,而多数bHLH家族成员受冷冻胁迫上调。(3)功能富集结果表明,多年生黑麦草差异表达的转录因子基因主要参与植物激素信号转导、昼夜节律和病原体互作等通路。研究表明,多年生黑麦草中与胁迫适应相关的转录因子基因普遍上调表达,而与生长和抗病相关的基因多数下调。该研究筛选到大量抗逆转录因子候选基因,为分子育种提供抗逆基因资源。     

低温胁迫后抗寒茶树品种‘紫阳圆叶’的基因差异表达分析

采用DDRT—PCR技术,对低温（4℃）胁迫处理不同时间（0、8、12、24和48h）后茶树[Camellia sinensis（Linn．）O．Ktze．]抗寒品种‘紫阳圆叶’（‘Ziyangyuanye’）叶片中差异表达的基因进行分离和测序,并采用半定量RT-PCR对差异表达基因的表达特性进行了比较。结果表明：有12个引物对扩增出有明显差异的cDNA片段,其中3个片段是与抗寒性相关的差异片段,分别被命名为Csgsf．Cscafl和Cscaf2,碱基数分别为217、316和232bp。比对结果显示：Cscaf与茶树品种‘安吉白茶’（‘Anjibaicha’）和‘龙井43’（‘Longjing43’）的谷氨酰胺合成酶基因的同源性分别为96％和91％,与菜豆（Phaseolus vulgaris Linn．）、蒺藜苜蓿（Medicago truncatula Gaertn．）、油棕（ElaeisguineensisJacq．）、西洋参（Panax quinquefolius Linn．）和水稻（Oryza sativa Linn．）等植物的谷氨酰胺合成酶的基因序列同源性均达到90％以上,因此,Cscafl应为茶树谷氨酰胺合成酶基因片段;Cscaf2与干旱胁迫条件下茶树表达的cDNA的同源性为100％,为茶树应答干旱和低温胁迫的基因片段;Cscafl未检索出同源序列,推测其为与冷胁迫相关的未知基因片段。半定量RT—PCR分析结果表明：Cscafl和Cscafl在低温胁迫的初始期即开始表达且表达量随低温胁迫时间延长逐渐下调;而Cscaf2的表达量随低温胁迫时间延长逐渐上调并在胁迫48h后达到最大,3个片段的表达特性均与差异扩增结果相符。     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.