兰科植物菌根真菌的研究进展

兰科（Orehidaceae）是仅次于菊科（Composltae）的一个兴盛、复杂的植物类群,广布于全球,多数种是著名的药用植物和珍贵花卉。兰科植物具有三大特点：第一、其花形状奇特,色彩艳丽,芳香宜人,授粉机制独特而复杂;第二、种子细小,仅具未分化的原胚;第三、在生活史中,与真菌共生形成内生苗根。因而,长期以来受到人们的普遍喜爱,带来了较高的商业利益,科学家,园艺工作者也从各个角度对兰科植物作了大量的研究。本文从兰科菌根的共生物之———菌根真菌的角度对有关其分类及与植物之间的专一性的研究状况进行了分析讨论,旨在为从…     

植物响应盐胁迫组学研究进展

盐胁迫对植物生长的影响主要表现在离子毒害、渗透胁迫以及次级氧化胁迫等,植物遭受盐胁迫时迅速启动相关基因,进行转录调控,进而合成相应蛋白质来控制代谢物合成和离子转运以调节渗透平衡。随着现代分子生物学迅速发展,对植物耐盐机理研究也深入到了转录组、蛋白质组、代谢组及离子组等水平,"组学"研究为耐盐基因鉴定及标志性代谢物的挖掘等提供了有力手段。该文对近年来国内外有关转录组学、蛋白质组学、代谢组学、离子组学的主要研究方法及在盐胁迫中的应用研究进展进行综述,以揭示植物耐盐机理,为优良耐盐碱植物的筛选与培育提供支持。     

非洲猪瘟病毒研究进展:组学视角

非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)引起的一种致死率可高达100%的猪烈性传染病。ASF的传播方式复杂多样,目前无商品化疫苗可用,仅能依靠检疫结合扑杀进行防控,严重威胁全球养猪及相关行业的健康发展。阻碍ASF疫苗研发的主要因素是ASFV的基因型众多、结构复杂,以及对ASFV致病和免疫逃逸机制的认识不足。本文从基因组学、转录组学、蛋白质组学和代谢组学等层面多角度综述ASFV的生物学特性及其致病和免疫逃逸机制,以期揭开ASF这个"杀手"的神秘面纱,为ASFV的致病机制研究和ASF的防控提供参考。     

植物与病原真菌互作机制研究进展

植物与病原真菌之间的互作是当今植物病理学研究的热点问题之一,相关的研究有望为植物抗病机制的解析和抗病品种的选育奠定理论基础。我们从形态、细胞、生理生化和分子等水平综述了植物与病原真菌互作机制的研究进展。     

多组学前沿技术专刊序言

后基因组时代,基因组学、转录组学、蛋白质组学及代谢组学等技术应用日趋广泛,功能注释成为生命科学研究的中心任务,多组学整合分析成为全面解析生物学机理的主要手段。本专刊邀请了国内多组学领域的相关专家学者介绍了基因组学、转录组学、蛋白质组学及代谢组学等领域最新进展和应用成果,收录了相关文章28篇,以供从事多组学研究的科研工作者参考。     

菌根真菌与兰科植物生境选择的相关性研究进展

随着基因测序技术的发展,研究者获取了大量有关兰科菌根真菌群落组成的信息。这些信息为探究菌根真菌与兰科植物的生境选择之间的相关性提供了有力证据。综合过去近10年的研究结果,根据兰科植物广域分布、异质性生境、小生境共存以及生态位分化等分布特征,对不同分布特征的兰科菌根真菌群落组成差异进行了梳理归纳,发现：广域分布的兰科植物通常具有泛化的菌根特征,或其特定的真菌伙伴亦具有广域分布特征;异质性生境会导致兰科菌根真菌群落组成差异,暗示菌根真菌在兰科植物适应不同异质性生境过程中具有特殊的生态功能;在同一区域中共存的兰科植物,其菌根真菌群落组成具有显著差异,有效避免了不同种兰科植物对同种养分的竞争;不同生态位分化的兰科植物,其菌根真菌群落组成具有显著差异,表明菌根真菌在宿主植物的生态位分化过程中亦起到重要作用。未来还应在大尺度空间兰科植物的菌根真菌类群变化、促进种子萌发特异性真菌类群以及菌根真菌的生态功能等方面加强研究。期望能为从事相关研究的业界同仁提供参考,并为兰科植物多样性保护及生态恢复提供理论参考。     

外生菌根真菌的共生互作和宿主选择机制研究进展

外生菌根真菌作为树木的共生伙伴,是森林生态系统重要组成部分,在森林天然更新、植物抗逆性形成、协助植物吸收限制性营养等方面扮演重要角色。真菌和植物跨界共生具有复杂的分子互作过程,在共生的不同阶段有不同的分子互作机制,其调控反馈网络还有许多未知。基因组与转录组研究技术和方法的进步,为一些新的信号分子、效应蛋白以及相关通路的发现提供了可能。真菌与宿主植物之间营养转移调控对共生的影响也逐渐受到关注,营养相关的转运蛋白对共生的建立和维持提供了物质基础。真菌的宿主选择机制是值得重点关注的领域,由于外生菌根真菌的多谱系起源和演化史中存在多次宿主转换事件,真菌演化出多样的应对机制用来区分相容性宿主、不相容性宿主和非宿主。通过对不同真菌与宿主植物的组学研究,宿主选择机制研究取得了一定进展。本文对近十年来国内外的研究报道进行梳理与总结,并对未来在该领域的探索方向做出展望。     

菌根真菌与兰科植物氮营养关系的研究进展

兰科植物是典型的菌根植物。兰菌根是兰科植物根与真菌形成的菌根共生体。兰菌根真菌的营养来源影响宿主植物的生活方式和营养水平。氮是植物生长的主要限制因子。兰科植物具有富集氮的特征, 其组织和器官的氮含量通常高于同生境中的其他植物。该文综述了兰菌根真菌类别、兰科植物氮营养特征和兰菌根的氮转移机制等的研究进展, 以期为兰科植物资源的保护、再生及可持续利用的相关研究提供参考和借鉴。     

兰科菌根真菌研究方法的概述

兰科植物资源在全球分布广泛,其中有许多是重要的药用植物和名贵的珍稀花卉,由于具有较高的商业价值,受到各界人士的广泛关注。兰科植物生长习性的特殊性导致其在自然状态下繁殖率极低,因此难以满足市场的广泛需求。近年研究表明,几乎所有兰科植物都能与相应的菌根真菌建立共生关系,并且必须依赖于这些内生真菌才能完成其整个生活史。因而对菌根真菌在提高兰科植物生长速度和繁殖能力过程中机制的研究以及将研究成果运用于工业化育苗中将是缓解兰科植物市场供求紧张问题的关键。通过对近几年有关天麻和铁皮石斛等兰科植物的问题研究中所采用的研究方法加以阐述,以期对今后兰科菌根真菌的研究提供一定的参考。     

植物与内生真菌互作的生理与分子机制研究进展

在自然生态系统中,植物组织可作为许多微生物定居的生态位.内生真菌普遍存在于植物组织内,与宿主建立复杂的相互作用(互惠、拮抗和中性之间的相互转化),并且存在不同的传播方式(垂直和水平传播).内生真菌通过多样化途径来增强植物体的营养生理和抗性机能.但这种生理功能的实现有赖于双方精细的调控机制,表明宿主和真菌双方都进化形成特有的分子调控机制来维持这种互惠共生关系.环境因子(如气候、土壤性质等)、宿主种类和生理状态、真菌基因型的变化都将改变互作结果.此外,菌根真菌和真菌病毒等也可能普遍参与植物-内生真菌共生体,形成三重互作体系,最终影响宿主的表型.研究试图从形态、生理和分子水平阐述内生真菌与植物互作的基础.     

生物组学在污染环境微生物修复研究中的应用

随着分子生物学、生物信息学和各种理化检测技术的发展,特别是人类基因组计划成功实施以来,基因组学研究取得了重大突破与进展。而包括转录组学、蛋白组学和代谢组学在内的后基因组学也相继出现,并被广泛应用在环境微生物学的各个研究领域。本文主要概述了当前基因组学、转录组学、蛋白质组学和代谢组学在污染环境生物修复研究中的最新研究进展,分析比较了各组学的优势与不足,同时结合本课题组的主要研究方向探讨了各生物组学在赤潮生消过程和有机污染物降解机理等研究中的应用。     

组学技术评价转基因农作物的非预期效应

安全性评价是转基因农作物商品化应用的必要环节。组学技术能在转录物、蛋白质、代谢物水平上对转基因农作物进行无偏倚的安全性评价。文章综述了近10年来应用转录组学、蛋白质组学和代谢物组学技术评价转基因农作物非预期效应的研究进展, 结果表明在转基因农作物非预期变异中, 环境因素(种植地点和季节)和基因型差异比转基因本身的影响更大。     

菌根真菌提高植物抗旱性机制的研究回顾与展望

菌根真菌与全世界约97％的维管植物具有广泛的共生关系.大量研究结果显示菌根植物相比于非菌根植物对于干旱胁迫具有更高的耐受性,说明菌根真菌在植物抗旱过程中发挥着重要作用.本文对近年来国内外在菌根真菌协助植物抵御干旱作用机制方面的研究进行了归纳和总结,主要包括在干旱胁迫下菌根真菌对植物生理学特性的影响机制、菌根真菌提高植物...     

菌根真菌在改善附生兰干旱耐受性中的作用：以禾叶贝母兰为例

干旱胁迫是在多种生态系统中影响植物生存、发育及产量的最主要的非生物因素之一。菌根共生已被证明可以提高植物对干旱的耐受性。兰科植物对菌根真菌有非常高的依赖性,但是有关兰科菌根真菌是否可以提高宿主植物的耐旱性以及能提高到什么程度还少有报道。在本研究中,我们检测了一株分离自附生型兰科植物禾叶贝母兰Coelogyne viscosa的胶膜菌属真菌Tullasnella sp. hy-111对宿主植物幼苗生长及耐旱性的影响,并从转录组水平检测了该菌根真菌对禾叶贝母兰幼苗基因表达的影响。结果显示,接种hy-111不仅能显著提高幼苗的生物量、与耐旱相关的酶活性以及渗透调节物质的富集,而且还能显著诱导植物抗性途径相关基因的上调表达。本研究表明菌根真菌能改善生长于胁迫的附生生境中的兰科植物对于干旱的耐受性,并可能在兰科植物的生态适应中起到重要作用。     

Dispersal of arbuscular mycorrhizal fungi and plants during succession

Arbuscular mycorrhizal (AM) fungi are important root symbionts that enhance plant nutrient uptake and tolerance to pathogens and drought. While the role of plant dispersal in shaping successional vegetation is well studied, there is very little information about the dispersal abilities of AM fungi. We conducted a trap-box experiment in a recently abandoned quarry at 10 different distances from the quarry edge (i.e. the potential propagule source) over eleven months to assess the short term, within-year, arrival of plant and AM fungal assemblages and hence their dispersal abilities. Using DNA based techniques we identified AM fungal taxa and analyzed their phylogenetic diversity. Plant diversity was determined by transporting trap soil to a greenhouse and identifying emerging seedlings. We recorded 30 AM fungal taxa. These contained a high proportion of ruderal AM fungi (30% of taxa, 79% of sequences) but the richness and abundance of AM fungi were not related to the distance from the presumed propagule source. The number of sequences of AM fungi decreased over time. Twenty seven plant species (30% of them ruderal) were recorded from the soil seed traps. Plant diversity decreased with distance from the propagule source and increased over time. Our data show that AM fungi with ruderal traits can be fast colonizers of early successional habitats.     

Profiling microbial lignocellulose degradation and utilization by emergent omics technologies

The use of plant materials to generate renewable biofuels and other high-value chemicals is the sustainable and preferable option, but will require considerable improvements to increase the rate and efficiency of lignocellulose depolymerization. This review highlights novel and emerging technologies that are being developed and deployed to characterize the process of lignocellulose degradation. The review will also illustrate how microbial communities deconstruct and metabolize lignocellulose by identifying the necessary genes and enzyme activities along with the reaction products. These technologies include multi-omic measurements, cell sorting and isolation, nuclear magnetic resonance spectroscopy (NMR), activity-based protein profiling, and direct measurement of enzyme activity. The recalcitrant nature of lignocellulose necessitates the need to characterize the methods microbes employ to deconstruct lignocellulose to inform new strategies on how to greatly improve biofuel conversion processes. New technologies are yielding important insights into microbial functions and strategies employed to degrade lignocellulose, providing a mechanistic blueprint in order to advance biofuel production.     

Building a mycorrhizal cell: How to reach compatibility between plants and arbuscular mycorrhizal fungi

Abstract

Arbuscular mycorrhizal fungi occur throughout the majority of ecosystems supporting host plant nutrition. Recent findings describe the accommodation of the fungus by the root cell as a crucial step for compatibility between the partners. We discuss here the novel aspects of cellular plant-fungus interactions, with a particular attention to the interface compartment, the unique apoplastic space hosting intracellular fungal structures. The main features of arbuscular mycorrhizal colonization are examined and recent information in the field of plant and fungal cell responses during the establishment of the symbiosis is discussed. Differences between the colonization of root epidermal and cortical tissues are discussed, highlighting the growing interest in the role of epidermal cells during the first and decisive steps of the symbiosis. New approaches such as root organ cultures, in vivo observations, GFP tagging and mutant plant analysis are commented on and information from these is compared with that gained from more traditional methods. In particular, the use of plant mutants is depicted as a powerful tool for dissecting and understanding the genetic and cellular aspects of plant/fungus compatibility. Finally, perspectives in this field are outlined through the application of these approaches to the currently unanswered questions.     

Symbiotic germination and development of myco-heterotrophic plants in nature: ontogeny of Corallorhiza trifida and characterization of its mycorrhizal fungi

The processes of symbiotic germination and seedling development were analysed in the myco-heterotrophic orchid Corallorhiza trifida , seeds of which were buried in 'packets' either adjacent to or at varying distances from adult plants in defined communities of ectomycorrhizal tree species. Germination occurred within eight months of burial under Betula – Alnus and within seven months under Salix repens . It was always associated with penetration of the suspensor by a clamp-forming mycorrhizal fungus. Four distinct developmental stages were defined and the rates of transition through these stages were plotted. There was no evidence of a relationship between extent of germination or rate of development and the presence of naturally distributed plants of C. trifida at the spatial scale of 1 m. The best germination and the most rapid rate of development of C. trifida seedlings occurred in a Salix repens community located at a considerable distance from any extant C. trifida population. Determination of internal transcribed spacer (ITS) RFLPs and of gene sequences of the fungi involved in symbiotic germination and growth of C. trifida , revealed them to belong exclusively to the Thelephora – Tomentella complex of the Thelephoraceae. These fungi are known also to be ectomycorrhizal associates of trees. It is hypothesized that the rate of growth of the C. trifida seedlings is determined by the ability of the fungal symbionts to transfer carbon from their ectomycorrhizal co-associates.