红蓝光调控茉莉开花的转录组分析

茉莉花是多年生常绿灌木植物,因其香气芬芳怡人,常被作为天然香料的原材料。本研究通过红光和蓝光分别处理茉莉植株,以白光模拟日光作为对照,观察茉莉植株开花早晚情况,结果表明,红光处理可促使茉莉花提前开花且增加花蕾数量,而蓝光延迟茉莉开花但花蕾数量减少,且各组之间花蕾数量差异显著。采用Illumina Hiseq/Miseq 2000高通量测序技术对红光组、蓝光组及白光组的顶芽部分进行转录组测序,共得到2 452 457条单基因簇(Unigene),其中1 760 723个Unigenes注释到GO、COG、KEGG、KOG、NR、Pfam、Swiss-Prot、NOG数据库。差异表达基因分析显示,对照组vs红光组共获得894个DEGs,对照组vs蓝光组共获得2 690个DEGs,红光组vs蓝光组共获得3 828个DEGs,共有的DEGs有72个。KEGG富集分析显示对照组vs红光组与对照组vs蓝光组共有的显著富集通路包括次生代谢物生物合成、苯丙素生物合成、吲哚生物碱生物合成、光合作用、植物激素信号传导和植物-病原体相互作用等,并从中筛选出24条差异表达基因,采用荧光定量PCR技术检测其表达水平,进行相关性分析,结果表明与转录组数据显著相关。通过对转录组数据进一步分析,发掘出大量调控开花相关的激素(IAA、ETH、GA、CTK、ABA、SA、JA)信号转导基因、开花途径相关调控基因(PHY、CRY1、FPA、AGL和SOC1)以及转录因子(bHLH、MYB、WKRY)家族基因,有助于阐明不同光质调控茉莉开花的差异表达机理。     

UV-B对雨生红球藻生长及虾青素积累的影响

以雨生红球藻(Haematococcus pluvialis)为材料, 研究不同强度的UV-B对雨生红球藻生长、光合作用及虾青素积累的影响和其作用机理。设置5种紫外线强度, 分别在正常光照培养条件下补充不同强度UV-B(100—500 lx), 标记为CK、U100、U200、U300、U400和U500六组。结果表明, 经UV-B辐射后雨生红球藻细胞密度、PSⅡ最大光化学效率(F_v/F_m)、非光化学淬灭系数(NPQ)和叶绿素(Chl.a和Chl.b)含量等均呈现下降趋势, 且与辐射强度相关。相反, 虾青素含量在100—400 lx强度下随UV-B辐射强度的增加而升高。与对照相比, 高强度UV-B辐射(U400)36h和72h后藻细胞虾青素含量分别提高了35.68%和56.23%, 达到5.82和7.06 mg/L。qRT-PCR检测发现雨生红球藻虾青素合成关键酶基因(IPI、PSY、BCH和BKT)的表达量随紫外辐射强度和辐射时间的增加均有不同程度升高。UV-B辐射亦调控紫外光受体UVR8及其信号转导通路核心元件(COP1、SPA1、HYH和HY5)的基因表达, 暗示上述基因参与了UV-B诱导雨生红球藻虾青素积累的过程。研究揭示紫外光受体UVR8介导的信号转导通路可能参与虾青素合成的转录调控, 为建立应用UV-B辅助光源促进雨生红球藻富集虾青素的工艺提供了基础, 同时为解析光诱导雨生红球藻虾青素积累的转录调控机制提供了新的视角。     

莱茵衣藻丝/苏氨酸蛋白激酶突变株蓝光响应的表征

为研究莱茵衣藻丝/苏氨酸蛋白激酶(silk/threonine protein kinase, STK)介导藻细胞蓝光响应的分子机制，本文对蓝光胁迫下莱茵衣藻STK突变株系crstk11(AphvIII盒反向插入stk11基因编码区)进行表型鉴定及转录组分析。表型鉴定显示，正常光(白光)下，野生型株CC5325与突变株crstk11的生长和色素含量差异较小；蓝光抑制了crstk11藻细胞生长和叶绿素合成，但显著促进类胡萝卜素积累。转录组分析显示，蓝光处理4 d，突变株(STK4) vs.野生型(wild type, WT4)共检测到差异表达基因(differential expression genes, DEGs) 860条(559个上调，301个下调)。高蓝光处理8 d,STK8 vs. WT8共获得1 088个DEGs (468个上调，620个下调)。KEGG富集分析发现，与CC5325相比，crstk11蓝光响应基因主要参与胞内光合作用催化活性、碳代谢和色素合成等。其中，上调基因包括psaA、psaB和psaC,psbA、psbB、psbC、psbD、psbH和psbL,pet...     

佐夫色绿藻高产虾青素突变体的筛选及虾青素合成机理研究

为了提高佐夫色绿藻(Chromochloris zofingiensis)细胞内虾青素含量,研究通过甲基磺酸乙酯诱变构建了含有20000个单克隆的突变体库,并筛选出一株高产虾青素的突变体12C10。在异养正常培养条件下,当葡萄糖耗完时, 12C10虾青素含量比野生型提高74%;缺氮诱导第4天时,虾青素含量比野生型高25%。利用广泛靶向代谢组学分析在正常培养条件下12C10与野生型在代谢物水平上的差异。与野生型相比, 12C10中除谷氨酸外的氨基酸及脂肪酸的合成普遍下降,但是谷氨酸的水平显著提高。氨基酸和脂肪酸合成减少为虾青素合成提供更多的碳骨架、NADPH和ATP。谷氨酸的积累可能一方面刺激了磷酸戊糖途径中6-磷酸葡萄糖脱氢酶的活性促进NADPH的产生,另一方面导致氧自由基产生促进虾青素合成。代谢物组分析结果还表明12C10中虾青素合成的增强可能与乙烯合成的增强有关。研究为进一步通过代谢调控提高C. zofingiensis虾青素含量奠定了基础,对指导C. zofingiensis虾青素积累新工艺的开发具有重要意义。     

不同光质对黍子(Panicum miliaceum)叶绿体光系统发育及psbA基因转录物稳态含量的影响

本文以一种C4植物——黍子(Panicum miliaceum)为材料,在白光、红光、蓝光、远红光和黑暗5种不同条件下培养黍子幼苗,叶片采收后用于叶绿素积累、叶绿体吸收光谱、叶绿体低温荧光发射光谱和高分子量cpRNA积累的测定以及psbA基因的Northern Blot分析。结果表明:白光、红光和蓝光下生长的黍子,它们的叶绿体都有功能完善的光合系统;而远红光下生长的黍子,已有光系统Ⅱ的发射峰,只是强度和波长都与白光、红光和蓝光下的有所不同;不同光质促进叶绿素积累和高分子量cpRNA积累的效率是平行的,其中红光较蓝光和远红光有效,而复合光(白光)的作用效果最好。当以白光诱导的积累量为100％时,可以分别求出不同光质诱导叶绿素积累和高分子量cpRNA积累的相对量,结果表明,高分子量cpRNA的积累对光的依赖性要比叶绿素积累对光的依赖性大得多。psbA基因的Northern Blot分析表明,不同光质下psbA转录物的积累与高分子量cpRNA的积累是一致的。据此我们推测,在黍子叶绿体的光诱导发育过程中,psbA的转录过程可能不受光信号的直接调控,而是受叶绿体整体发育状态的控制。     

G蛋白偶联受体相关分选蛋白功能特征与相关疾病研究进展

G蛋白偶联受体(G protein-coupled receptors, GPCRs)作为最大的一类膜蛋白受体家族,可被多种配体激活并发挥相应的信号转导功能,参与生物体内重要的生理过程。G蛋白偶联受体相关分选蛋白(G protein-coupled receptors associated sorting proteins, GASPs)则对内吞后的GPCRs分选过程发挥着重要的作用,并介导受体进入降解或再循环途径,进而调控细胞的信号转导等过程。研究发现GASPs的功能缺陷与多种疾病相关,包括神经系统疾病、肿瘤和耳聋等。本文重点介绍了G蛋白偶联受体相关分选蛋白的功能特征及其相关信号通路,描述了GASPs功能缺陷与疾病的关联性及家族蛋白与GPCRs的相互作用、GASPs分选途径的发现、参与的信号通路及对基因转录调控,以期为GASPs相关多种疾病的治疗提供新的思路和策略。     

棉铃虫雌雄性腺转录组的比较分析

【目的】棉铃虫Helicoverpa armigera(Hübner)是我国重要的农业害虫,生殖力强是其发生为害的内在生物学基础,而已知的与棉铃虫生殖相关的基因信息相对较少,本研究旨在筛选棉铃虫性腺发育的相关基因。【方法】通过高通量测序技术对棉铃虫成虫的卵巢和精巢进行转录组测序。【结果】共获得100 603条unigenes,平均长度为666.05 bp,其中N50为1 114 bp。经同源性比对,52 071条unigenes获得注释信息,其中注释到Nr数据库的序列最多。通过比较转录组分析发现,在棉铃虫精巢和卵巢中存在7 714个差异表达的基因（Differentially expressed genes,DEGs）,其中3 288个DEGs表达水平在卵巢中上调,4 426个DEGs在精巢中上调。差异基因富集结果涉及到生殖系统发育的相关通路有mTOR信号通路、卵母细胞减数分裂、促性腺激素释放激素信号通路和胰岛素信号通路等。同时筛选得到部分与性腺发育相关的基因,包括vitellogenin(Vg)、vitellogeninreceptor(Vg R)、chorion-relatedgene、testis-specific serine/threonine-protein kinase和spermatogenesis-associated protein等。选取其中12个DEGs用实时荧光定量检测其表达量,结果表明RT-qPCR与RNA-Seq的结果一致。【结论】本研究获得了棉铃虫雌雄性腺的转录组数据及主要性腺发育相关基因,将有助于丰富棉铃虫繁殖相关的基因资源,为进一步研究棉铃虫生殖调控机理提供基础数据。     

光受体介导信号转导调控植物开花研究进展

光照是影响植物生长发育的重要环境因子, 开花是高等植物生活史上最重要的事件。植物通过光受体感知外界环境中的光照变化, 激活一系列信号转导过程从而适时开花。该文介绍了高等植物光受体的种类、结构特征和生理功能的研究进展, 并系统阐述了红光/远红光受体光敏色素、蓝光受体隐花色素以及FKF1/ZTL/LKP2等介导光信号调控植物开花的分子机制, 包括光受体对CO转录及转录后水平调控和对FT转录水平的调控等。此外, 还介绍了光受体整合光信号与温度和赤霉素等信号调控植物开花的研究进展, 并展望了未来的研究方向。     

球囊菌胁迫中华蜜蜂幼虫肠道过程中病原的转录组学研究

【目的】本研究利用RNA-seq技术对球囊菌胁迫的中华蜜蜂(中蜂)幼虫肠道进行深度测序,经趋势分析得到差异表达基因(DEGs)的显著表达模式,进而对胁迫过程中的球囊菌进行转录组学分析。【方法】利用Illumina HiSeq 2500平台对球囊菌胁迫的中蜂幼虫肠道进行深度测序,并利用相关软件进行了深入分析。最后,通过RT-qPCR对RNA-seq数据进行了验证。【结果】本研究共得到球囊菌的41133932条高质量clean reads。22865个DEGs共聚类为8个基因表达模式,其中,16769个DEGs聚类为2个显著上调趋势与2个显著下调趋势。GO富集分析结果显示,显著上调与显著下调趋势中的DEGs分别富集于40与37个GO term,基因富集数最多的为细胞进程(2486 unigenes)。KEGG代谢通路(pathway)富集分析结果显示,显著上调与显著下调趋势中的DEGs分别富集于119和112个pathway,基因富集数最多的分别是氨基酸生物合成(127 unigenes)与核糖体(98 unigenes)。进一步分析表明球囊菌在胁迫中蜂幼虫肠道的过程中通过提高物质合成促进其增殖,而宿主通过抑制球囊菌的蛋白合成抵御病原入侵。富集在MAPK信号通路的11个DEGs的表达水平随着胁迫时间的延长而逐渐下降,推测中蜂幼虫通过抑制该通路而阻遏球囊菌增殖。【结论】本研究不仅为揭示白垩病过程中的球囊菌-中蜂幼虫互作提供了重要信息,也为阐明不同抗性蜂种的球囊菌抗性差异奠定了基础。     

不同光强光质对艾草生长及挥发油成分积累的影响

为探究光照对艾(Artemisia argyi)的产量及主要挥发油成分积累的影响,以蕲艾组培苗为试材,采用高光强、红光、蓝光等进行不同光强光质处理实验。结果表明,高光强及蓝光处理可促进艾生物量积累,红光和蓝光处理可促进植株伸长。高光强、红光及蓝光均可提高艾叶挥发油中1,8-桉油素、β-萜品醇含量。高光强还能促进龙脑积累,而蓝光处理下可检测到较多在其他光照条件下未检测到的化合物,如萜烯和蓝桉醇等物质。对不同光强光质处理下光受体及光响应转录因子基因表达量进行分析,在高光强处理下,所有光受体的表达量均显著升高;而响应不同光质的对应光受体基因表达量增加。光受体基因表达与艾生物量及主要挥发油的相关性分析表明,光受体基因表达对艾草生物量的影响起重要作用,且不同光处理调控可通过光受体响应并级联调控相关基因表达,调控艾叶生长及挥发油的合成。高光强和蓝光处理下,艾草的生物量及有效挥发油代谢物增加,可在艾草栽培中加以应用。     

真菌发育过程中的蓝光诱导

本文对多种真菌在发育过程中受蓝光诱导的现象进行了综述。蓝光可以诱导多种真菌的形态发生和发育,包括孢子的产生和菌丝的延伸等。此外,蓝光还可引起真菌的生理和生化改变,如细胞膜对离子的通透性的变化、类胡萝卜素的合成等。真菌也存在一个蓝光信号系统,通过蓝光受体接受蓝光信号,导致了真菌的一系列形态发生和生理生化的变化。     

Effect of latitude on flavonoid biosynthesis in plants

The growth conditions in different latitudes vary markedly with season, day length, light quality and temperature. Many plant species have adapted well to the distinct environments through different strategies, one of which is the production of additional secondary metabolites. Flavonoids are a widely spread group of plant secondary metabolites that are involved in many crucial functions of plants. Our understanding of the biosynthesis, occurrence and function of flavonoids has increased rapidly in recent decades. Numerous studies have been published on the influence of environmental factors on the biosynthesis of flavonoids. However, extensive long‐term studies that examine the effect of the characteristics of northern climates on flavonoid biosynthesis are still scarce. This review focuses on the current knowledge about the effect of light intensity, photoperiod and temperature on the gene–environment interaction related to flavonoid biosynthesis in plants.     

Are two photoreceptors involved in the flowering of a long-day plant?

The effect of daylength extension with narrow spectral bands on the flowering of a long-day plant, Brassica campestris L. cv. Ceres, was investigated to obtain clues to the identity of the photoreceptor involved. Extension of a 9 h photoperiod with 5 h of light pulses at various wavelengths resulted in maximal flowering occurring after irradiation at 710 nm, less at 730 nm, and none at 550, 660 and 750 nm. Flowering at 710 and 730 nm was negated by simultaneous exposures at 550 nm, but not at 660 nm. A short preirradiation at 660 nm enabled a following irradiation at 750 nm to induce flowering. This latter induction was prevented by 550 nm irradiation.
Short flashes of light at 710 nm induced flowering that was negated by a following flash at 550 nm but not at 660 nm. The negation by 550 nm radiation was prevented by subsequent flashes at 710 nm, indicating photoreversibility. A flash at 660 nm enabled subsequent light flashes at 750 nm to initiate flowering that was reversed by a following 550 nm flash.
From the results showing the necessity of red and far-red lights, it is proposed that flowering in this long-day plant is due to two photoreceptors - one is phytochrome and the other an unknown pigment with far-red, green photoreversible properties. By using fluence response data, it is deduced that the unidentified photoreceptor has weak absorption bands in the far-red, but has a strong absorption band in the green. Flowering is induced when effects of red light absorbed by phytochrome interact with effects of far-red light absorbed by the unidentified photoreceptor.     

Aspects of photoinduction of carotenogenesis in the fungus Verticillium agaricinum

An action spectrum for light induced carotenogenesis in Verticillium agaricinum (Link) Corda (ATCC 24668) was obtained by exposing mycelial pads to monochromatic radiation. Action maxima occurred at 290 (main peak) and 390 nm, and there was a minor peak at 483 nm. The results also showed interaction between the blue and UV light. Blue light partly reversed the UV light induction of carotenogenesis when given after, but not when given before UV light. This implies that there are at least two photoreceptors involved in carotenogenesis in Verticillium , but phytochrome is not likely to be one of them.     

光质及种子大小对普洱地区14种植物种子萌发的影响

以普洱地区14种常见植物种子为材料,在实验室条件下研究了其在白光、黑暗、红光和蓝光条件下的萌发特性,并分析了种子大小与萌发率、萌发速率、萌发开始时间的关系。结果表明:光质对四方蒿、沙针、尖子木、藿香蓟种子萌发率和萌发速率均有显著影响(P0.05)。光质对大叶斑鸠菊、云南山枇花、臭灵丹、车桑子、光萼猪屎豆、葫芦茶、云南地桃花、西南宿苞豆、岗柃、中国宿苞豆10个物种的种子萌发率和萌发速率均没有显著影响(P0.05),以上物种中除中国宿苞豆外,其他物种种子萌发率均在20%以下,处于休眠状态。四方蒿种子在白光(89.9%)和红光(84.7%)下萌发率最高,红光下种子萌发最快(4.93),蓝光下种子萌发开始时间最晚(11.3 d);沙针种子在白光下萌发率最高(80.4%)、萌发速率最快(2.71),在黑暗和蓝光下萌发率较低(43.9%和38%)、萌发速率最慢(0.73和0.85),白光、红光下萌发开始最早(11 d),黑暗条件下萌发开始最晚(21.7 d);尖子木种子萌发率在白光、黑暗、蓝光下均在86%以上,而红光下仅32%且萌发速率最慢(1.29),在蓝光下萌发开始时间最晚(13 d);藿香蓟种子萌发率和萌发速率在红光下最高(分别为71.3%和6.46),黑暗条件下最低(分别为42.5%和2.62);大叶斑鸠菊萌发开始时间在黑暗条件下最早(6 d),其次是白光下(7 d),蓝光和红光下较晚,分别为8 d和7.7 d。14个物种种子的萌发率与种子大小间均有显著负相关关系;种子萌发速率、萌发开始时间与种子大小间也有负相关关系,但不显著;种子大小与萌发率、萌发速率和萌发开始时间的关系不会随着光质的变化而发生变化。     

Further support for the involvement of phytoehrome in stomatal movement

The involvement of phytochrome in stomatal movement in Commelina communis L. is indicated by the following observations: 1) Short irradiation with red or blue light causes opening, of isolated stomata and swelling of guard cell protoplasts. This is reversed by subsequent far red irradiation. 2) In a similar way, stomatal response to prolonged irradiation with red or blue light is decreased by concomitant far red irradiation. 3) Pretreatment with filipin, which interferes with phytochrome binding to membranes, decreases stomatal opening in red and blue light. The stomatal responses to blue and red light are modified by DCMU, N₂, CO_2-enriched atmosphere, and CO_2-free air, which are known to affect, among other processes, chlorophyll fluorescence. Increased chlorophyll fluorescence by DCMU, N₂ and CO₂-enriched atmosphere enhanced stomatal opening in blue light and inhibited it in red light. CO₂-free air, which decreases chlorophyll fluorescence, had the opposite effect.     

Survival in low light: photosynthesis and growth of a red alga in relation to measured in situ irradiance

Reduced light availability for benthic primary producers as a result of anthropogenic activities may be an important driver of change in coastal seas. However, our knowledge of the minimum light requirements for benthic macroalgae limits our understanding of how these changes may affect primary productivity and the functioning of coastal ecosystems. This knowledge gap is particularly acute in deeper water, where the impacts of increased light attenuation will be most severe. We examined the minimum light requirements of Anotrichium crinitum, which dominates near the maximum depth limit for macroalgae throughout New Zealand and Southern Australia, and is a functional analog of rhodophyte macroalgae in temperate low‐light (deep‐water) habitats throughout the world. These data show that A. crinitum is a shade‐adapted seaweed with modest light requirements for the initiation of net photosynthesis (1.49–2.25 μmol photons · m^?2 · s^?1) and growth (0.12–0.19 mol photons · m^?2 · d^?1). A. crinitum maintains high photosynthetic efficiency and pigment content and a low C:N ratio throughout the year and can maintain biomass under sub‐compensation (critical) light levels for at least 5 d. Nevertheless, in situ photon flux is less than the minimum light requirement for A. crinitum on at least 103 d per annum and is rarely sufficient to saturate growth. These findings reinforce the importance of understanding the physiological response of macroalgae at the extremes of environmental gradients and highlight the need to establish minimum thresholds that modification of the subtidal light environment should not cross.     

Action spectrum for fruiting in the basidiomycete Schizophyllum commune

An action spectrum for fruit body formation was determined in the range 280–723 nm for a dikaryon of Schizophyllum commune Fr. Action maxima occurred at 280 and 340–360 nm (main peak), and there were minor peaks at 437 and 467 nm. The quantum effectiveness at 360 nm was ca seven-fold compared to that of 437 nm light. Wavelengths longer than 500 nm were ineffective. Light also induced formation of brown pigment in the area producing fruit bodies. Wavelengths ranging from 260 to 300 nm injured aerial hyphae at the border of the colony. The possibility that a flavin or a pteridine may be the photoreceptor is discussed.     

Blue Light Reception in Phycomyces: Red Light Sensitization in madC Mutants

Sporangiophores of the zygomycete fungus Phycomyces blakesleeanus are sensitive to near UV and blue light. The quantum effectiveness of yellow and red light is more than 6 orders of magnitude below that of near UV or blue light. Phototropism mutants with a defect in the gene madC are about 10⁶ times less sensitive to blue light than the wild type. These mutants respond, however, to yellow and red light when the long wavelength light is given simultaneously with actinic blue light. In the presence of yellow or red light the photogravitropic threshold of madC mutants is lowered about 100-fold though the yellow and the red light alone are phototropically ineffective. A step-up of the fluence rate of broad-band red light (> 600 nm) from 6 × 10^?3 to 6W m^?2 elicits, in mutant C 148 madC, a transient deceleration of the growth rate. The growth rate of the wild type is not affected by the same treatment. The results are interpreted in terms of a red light absorbing intermediate of the blue light photoreceptor of Phycomyces. The intermediate should be short-lived in the wild type and should accumulate in madC mutants.