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关键词： CRISPRS (Genetics)   RESEARCH   PLANT viruses  

摘要： The article discusses work led by researcher Caixia Gao on plants that contain the CRISPR-Cas9 system, which makes them resistant to viral infections from geminiviruses.

关键词： 流式细胞术   DNA   C-值   基因组大小   杂草   入侵性   倍性  

摘要： 为了评估DNA C-值和基因组大小(genome size)在植物入侵性评估中的价值,应用流式细胞仪测定了长三角及邻近地区138种草本植物的核DNA含量,其中111种为首次报道。在此基础上比较了不同植物类群这两个值的差异,特别是入侵性与非入侵性植物这两个值的差异。结果表明:(1)138种草本植物平均DNA C-值为1.55 pg,最大者是最小者的37.17倍。127个类群平均基因组大小为1.08 pg,最大者是最小者的34.11倍;(2)统计了菊科(Asteraceae)、禾本科(Poaceae)、石竹科(Caryophyllaceae)、十字花科(Brassicaceae)、玄参科(Scrophulariaceae)、蓼科(Polygonaceae)、唇形科(Labiatae)和伞形科(Umbelliferae)的DNA C-值和基因组大小,发现禾本科植物的这两个值显著地大于其他7个科(P<0.01)。单子叶的DNA C-值和基因组极显著地大于双子叶植物(P<0.01);(3)杂草比非杂草具有更低的DNA C-值(P<0.01)和基因组大小(P<0.001);与DNA C-值相比,基因组大小在这两个类群之间的差异更为明显(P<0.001),这种现象也体现在菊科植物中。随着基因组(X1)和DNA C-值(X2)由大变小,植物的杂草性(入侵性,Y)由弱变强,两者关系分别符合:Y=2.2334-1.2847 ln(X1)(r=0.4612,P<0.01)和Y=2.4421-0.7234 ln(X2)(r=0.2522,P<0.01),DNA C-值和基因组大小可以作为植物入侵性评估的一个指标;(4)多倍体杂草的基因组极明显地小于二倍体杂草(P<0.01),前者为后者的0.63倍。在非杂草中,多倍体基因组比二倍体的略小,前者仅为后者的0.84倍,差异不显著(P>0.5)。菊科植物中多倍体杂草的基因组也显著地小于二倍体杂草(P<0.1)。基因组变小和多倍体化相结合,进一步增强了植物的入侵性。在多倍体植物入侵性评估中,基因组大小比DNA C-值更有价值。

关键词： 慈姑属   生态   进化   生态修复   表型可塑性   经典分类   谱系地理   生活史权衡  

摘要： 慈姑属(Sagittaria L.)隶属于泽泻科,是世界广布的水生植物,其生境多样、叶形和繁殖表型复杂,进化地位较特殊,是生态和进化生物学研究较典型的材料。笔者在查阅相关慈姑属研究的大量文献的基础上,对前人研究的物种、探讨的问题及研究结果进行了归纳与总结:慈姑属物种存在广布种和濒危种,且个别物种的濒危现状可能与其生境条件相关;慈姑属的个别种类成为稻田入侵杂草,其竞争能力因慈姑种类及水稻栽培品种的不同而各异;环境对慈姑属植物有很强的塑造作用,不同环境还会造成慈姑所在的水生植物群落结构发生变化;慈姑属植物具有较高的遗传多样性;在繁殖方面,慈姑属植物体现出不同繁殖方式和两性功能的权衡,以及在繁育系统上从雌雄同株到雌雄异株的进化途径。本文还提出了相关研究存在的不足、研究中应注意的科学问题,并对慈姑属植物未来的研究方向提供了新思路。

关键词： PLANT hormones   PHYTOTROPINS   CELLULAR signal transduction   TRANSCRIPTION factors   MOLECULAR genetics  

摘要： Auxin is a key regulator of plant growth and development. Classical molecular and genetic techniques employed over the past 20 years identified the major players in auxin-mediated gene expression and suggest a canonical auxin response pathway. In recent years, structural and biophysical studies clarified the molecular details of auxin perception, the recognition of DNA by auxin transcription factors, and the interaction of auxin transcription factors with repressor proteins. These studies refine the auxin signal transduction model and raise new questions that increase the complexity of auxin signaling.

关键词： cloning   DNA assembly   genetic syntax   GoldenGate   synthetic biology   Type IIS restriction endonucleases  

摘要： Inventors in the field of mechanical and electronic engineering can access multitudes of components and, thanks to standardization, parts from different manufacturers can be used in combination with each other. The introduction of BioBrick standards for the assembly of characterized DNA sequences was a landmark in microbial engineering, shaping the field of synthetic biology. Here, we describe a standard for Type IIS restriction endonuclease-mediated assembly, defining a common syntax of 12 fusion sites to enable the facile assembly of eukaryotic transcriptional units. This standard has been developed and agreed by representatives and leaders of the international plant science and synthetic biology communities, including inventors, developers and adopters of Type IIS cloning methods. Our vision is of an extensive catalogue of standardized, characterized DNA parts that will accelerate plant bioengineering.

关键词： agritechnology   CRISPR   Cas   DNA assembly   genome engineering   Marchantia   sustainable intensification   synthetic biology   TAL effectors  

摘要： Information about the annual summer meeting of the European Research Area Network for synthetic biology (ERASynBio) from September 14 to 20, 2014 is presented. Topics of the meeting include the concepts of synthetic biology, the new technologies in plant systems and the improvements in research for plant synthetic biology. The meeting was also attended by several biologists and researchers including Claes Gustafsson, Jim Haseloff and Ben Blount.

关键词： 植物提取物   生物学功能   作用机制  

摘要： 植物提取物是指一类来源于植物的,具有一种或多种生物学功能的活性物质,添加在饲料中能起到促生长、抗氧化、抗病毒、免疫增强等多种功能,且在畜产品中无残留,动物体内不易产生病原菌的抗药性。由于植物提取物种类的多样性,其生物学活性的作用机制也不尽相同,这其中包括对体内抗氧化酶在转录和翻译水平的调控、病原菌表面受体结合与穿透融和、介导免疫细胞信号通路、去瘤胃原虫作用、减少甲烷菌的增殖等多个方面。本文综述了当前对植物提取物的种类、生物学功能及作用机理的研究,为今后在此领域开展更深入的研究提供参考。

关键词： 苹果   专用授粉树   观赏海棠   盛花期   花粉特性   果实品质  

摘要： 为实现苹果单品种建园,选育适宜专用授粉树,研究了‘道格’、‘绚丽’、‘红丽’、‘满洲里’、‘雪球’5个观赏海棠品种的植物学、生物学性状、花粉特性及果实品质。结果表明,供试品种盛花期为4月7—20日,和栽培品种花期相遇,‘道格’和‘满洲里’花期较早,盛花期分别为4月7日、4月9日,‘绚丽’和‘红丽’均为4月12日,‘雪球’为4月20日。供试品种花粉量大,‘道格’、‘满洲里’、‘红丽’、‘雪球’和‘绚丽’分别为13384、13162、7426、6074、6003粒/花药。单果重‘道格’最大(12.98 g),其次是‘雪球’(10.66 g)、‘绚丽’(2.59 g),‘红丽’和‘满洲里’较小(均为2.00 g)。果型指数与单果重趋势基本一致。种子数不尽相同,‘红丽’和‘雪球’为7颗/果,‘满洲里’6颗/果,‘道格’和‘绚丽’为4颗/果。可溶性糖含量以‘道格’最高(18.49%),其次是‘满洲里’(16.33%)、‘雪球’(16.11%)、‘绚丽’(15.98%),‘红丽’较低为14.20%;可滴定酸‘红丽’最高为1.16%,‘绚丽’为0.99%、‘满洲里’为0.90%,‘道格’最低为0.80%。初步认为,供试品种适宜作为国内的苹果专用授粉树。

关键词： BOTANY   ARABIDOPSIS thaliana   PLANT growth   AGING in plants   FUNCTIONAL genomics   CONGRESSES  

摘要： The article offers information on the Institució Catalana de Recerca i Estudis Avançat (ICREA) Workshop on the significant advances in basic plant sciences by using the model plant Arabidopsis thaliana held in Barcelona, Spain on 7-8 May 2015. Topics discussed include plasticity of plant growth and development, senescence after flowering in plants and functional genomics for adapdation in plants.

关键词： BACTERIAL cells   PHOTOSYNTHESIS   PROTEIN-protein interactions   CYANOBACTERIAL metabolism   CARBON dioxide fixation  

摘要： Bacterial microcompartments (BMCs) are self-assembling organelles that sequester segments of biochemical pathways within a protein shell. Given their functional diversity, BMCs constitute a rich source of metabolic modules for applications in synthetic biology. The carboxysome, the cyanobacterial BMC for CO2 fixation, has attracted significant attention as a target for installation into chloroplasts and serves as the foundation for introducing other types of BMCs into plants. Carboxysome assembly involves a series of protein-protein interactions among at least six gene products to form a metabolic core, around which the shell assembles. This complexity creates significant challenges for the transfer, regulation, and assembly of carboxysomes, or any of the myriad of functionally distinct BMCs, into heterologous systems. To overcome this bottleneck, we constructed a chimeric protein in the cyanobacterium Synechococcus elongatus that structurally and functionally replaces four gene products required for carboxysome formation. The protein was designed based on protein domain interactions in the carboxysome core. The resulting streamlined carboxysomes support photosynthesis. This strategy obviates the need to regulate multiple genes and decreases the genetic load required for carboxysome assembly in heterologous systems. More broadly, the reengineered carboxysomes represent a proof of concept for a domain fusion approach to building multifunctional enzymatic cores that should be generally applicable to the engineering of BMCs for new functions and cellular contexts.