The plant cell wall.
The plant cell wall.
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DOI：
10.1111/jipb.12351
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发表时间：
2015-03
影响因子：
11.4
通讯作者：
K. Fagerstedt;A. Kärkönen
中科院分区：
文献类型：
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作者：
K. Fagerstedt;A. Kärkönen
在过去的几年里，对植物细胞壁的许多方面的研究经历了复兴。这可能主要是由于对具有工业用途：用于纤维的纤维素以及用于生物乙醇的半纤维素，用于塑料或生物燃料的木质素，作为凝胶剂的果胶，更不用说用于建筑或纸浆生产的木质细胞壁材料以及用于电子产品的智能材料-新用途是令人难以置信的！由于细胞壁材料是当时的炒作，对细胞壁材料的基本知识的压力越来越大。这强调可用于生物能源应用、合成和半合成聚合物生产、新型碳纤维甚至具有全新智能特性的聚合物的基础研究成果。如果没有细胞壁成分的结构和功能的基本信息，就不可能为这种旧材料发明巧妙的新用途。木材细胞壁含有木质素，一种酚类聚合物，高达细胞壁干物质的约32%。木质素是继纤维素之后地球上第二大最丰富的生物聚合物，它对细胞壁的结构完整性和植物体的刚度和强度起着至关重要的作用。单木酚的生物合成途径是众所周知的，但它们进入细胞壁的运输和体内聚合并不清楚，因此，关于漆酶和过氧化物酶在木质素聚合物形成中的作用的研究工作在Koutaniemi等人（2015年）关于挪威云杉木质素形成组织中的漆酶的文章和Shigeto等人（2015年）的文章中介绍了这一特殊问题。过氧化物酶双突变体对拟南芥木质素含量的影响。植物细胞壁也具有令人钦佩的可塑性。这一点在M elida等人（2015）关于“玉米细胞悬浮培养物的初级纤维素缺陷细胞壁中的异位木质化”和de Castro等人（2015）在其题为“纤维素缺陷玉米细胞中半纤维素的生物合成和壁结合：代谢可塑性的一个例子”的文章中得到了证实。木材形成是一个重要的生物学和经济学过程。树木和木材在许多国家相当重要，因为这些国家的国民总收入的很大一部分来自林业部门。为了能够生产具有目标特性的木材产品，我们需要更多关于木质部细胞壁基本结构及其组分生物合成的信息。这些信息对于通过传统育种方法和具有潜在高经济影响的遗传修饰来定向改变这些结构至关重要。Andersson等人（2015）的文章集中在压缩木材中细胞壁结构的变化，即在裸子植物的倾斜茎中形成的木材，并改变了锯材的特性-并不总是最好的！因此，重要的是要知道木材的微观结构发生了什么，以及如何补救或-另一方面-更好地利用。此外，Andersson等人的论文。（2015）从进化的角度来看很有趣，因为所研究的物种银杏可以被描述为活化石。许多细胞壁聚合物的生物合成是迷人的，但仍然有更多的知识空间，特别是在合成过程的调控方面。Liu et al.（2015）在其题为“细胞骨架网络与质膜和细胞壁的连接”的文章中对该研究领域进行了综述。细胞壁也已知在其形成期间和之后被修饰。Glass等人（2015）在他们的文章中报告说，内切葡聚糖酶可以对纤维素结晶产生影响;这种变化甚至可以导致拟南芥植物形态的显著变化。高通量技术，如Frankov a和Fry（2015）描述的转聚糖酶，将揭示有助于植物发育期间细胞壁组装和/或重组的新酶活性。随着全植物基因组测序越来越普遍，遗传和生物信息学分析的应用为植物材料的利用和作物新品种的培育提供了新的思路和新的可能性。Ermawar等人（2015年）在关于高粱中（1，3; 1，4）-b-葡聚糖的生物合成基因家族的文章中利用了这类信息，这对人类健康、动物饲料和生物燃料应用很重要。由于细胞壁相关问题在植物发育的基础生物学理解中非常重要，关于植物细胞壁的新文章每天都在出现。本期文章介绍了一些重要的化合物在功能和多功能的植物细胞壁的制作。
Research on the many aspects of the plant cell wall has experienced rejuvenation during the past few years. This is perhaps mainly due to the commercial interest in the chemical components of the cell wall that have potential for industrial use: Cellulose for fibers and together with hemicelluloses for bioethanol, lignin for plastics or biofuel, pectins as gel agents, let alone woody cell wall material for construction or pulp production and for intelligent materials for electronics – the new uses are mindboggling! As cell wall materials are the hype of the time, pressure on the basic knowledge of the cell wall materials is increasing. This emphasizes basic research results that can be used, for example, in bioenergy applications, in the production of synthetic and semi-synthetic polymers, and in new carbon fibers or even as polymers with altogether new and intelligent properties. Without the fundamental information on the structure and functions of the cell wall components, it is not possible to invent ingenious new uses for this old material. Wood cell walls contain lignin, a phenolic polymer, up to approximately 32% of cell wall dry material. Lignin is, after cellulose, the second most abundant biopolymer on earth, and it plays a crucial role for structural integrity of cell walls and for stiffness and strength of the plant body. The biosynthetic route for monolignols is well known but their transport into the cell wall and polymerization in vivo are not that clear, and hence, the research efforts on the laccases and peroxidases functioning in the formation of lignin polymer are presented in this special issue in the articles by Koutaniemi et al. (2015) on laccases in lignin-forming tissues of Norway spruce and by Shigeto et al. (2015) on the effect of peroxidase double mutants on lignin contents in Arabidopsis. Plant cell walls have also admirable plasticity. This is made evident in the two articles in this special issue by M elida et al. (2015) on ‘Ectopic lignification in primary cellulose-deficient cell walls of maize cell suspension cultures’, and by de Castro et al. (2015) in their article titled ‘The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells: An example of metabolic plasticity’. Wood formation is an important process with both biological and economical aspects. Trees and wood are of considerable importance in many countries where a large part of the gross national income comes from the forest sector. To be able to produce wood products with targeted characteristics, we needmore information on the basic structures in the xylem cell walls and on the biosynthesis of their components. This information is vital for directed changes in these structures through conventional breeding methods and through genetic modification with potential high economic impact. The article by Andersson et al. (2015) concentrates on changes in the cell wall structures in compression wood, i.e. wood that forms in leaning stems of gymnosperms, and alters the properties of sawn timber – not always for the best! Hence, it is important to know what has happened in the microstructure of wood and how this could be remedied or – on the other hand – made better use of. Furthermore, the paper of Andersson et al. (2015) is interesting in an evolutionary point of view, as the studied species, Gingko biloba, can be described as a living fossil. The biosynthesis of the many cell wall polymers is fascinating but there is still room for more knowledge, especially on the regulation of the synthetic processes. This research area is reviewed by Liu et al. (2015) in their article titled ‘The connection of cytoskeletal network with plasma membrane and the cell wall’. Cell wall is also known to be modified during and after its formation. Glass et al. (2015) report in their article that endoglucanases can have an impact on cellulose crystallization; the changes in this can lead into considerable changes even in the morphology of Arabidopsis plants. High-throughput techniques, such as that described by Frankov a and Fry (2015) for transglycanases, will reveal novel enzyme activities that contribute to cell wall assembly and/or restructuring during plant development. As the sequencing ofwhole plant genomes is gettingmore and more common, the use of genetic and bioinformatics analyses have given new ideas and reveal new possibilities in the use of plant material and breeding of new crop varieties. This kind of information is made use of in the article by Ermawar et al. (2015) on the biosynthetic gene families in sorghum for (1,3;1,4)-b-glucan, important in human health, animal feed and biofuel applications. As cell wall related issues are very important in fundamental biological understanding of plant development, new articles on the plant cell wall are emerging daily. The articles presented here in this issue give a glimpse into some of the vital compounds in the making of a functional and versatile plant cell wall.