Rapid changes in gene expression in response to microbial elicitation
Rapid changes in gene expression in response to microbial elicitation
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基因表达因微生物引发而快速变化
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
W. Schuch
中科院分区：
文献类型：
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作者：
R. Dixon;J. A. Bailey;J. Bell;G. Bolwell;C. Cramer;K. Edwards;M. Hamdan;C. Lamb;M. Robbins;T. Ryder;W. Schuch
用炭疽菌Colletotrichum lindemuthianum细胞壁的多糖激发子分子处理菜豆（Phaseolus vulgaris）的细胞悬浮培养物，导致菜豆植物抗毒素的快速积累、壁结合酚类化合物的沉积和富含羟脯氨酸的糖蛋白的合成。这些变化依赖于基因产物的高度选择性诱导，包括酶L-苯丙氨酸解氨酶、细胞色素P450依赖性肉桂酸4-羟化酶、查耳酮合酶、查耳酮异构酶、脯氨酰羟化酶和蛋白质：阿拉伯糖基转移酶。体内标记、体外翻译和RNA印迹杂交技术的应用表明，这些激发子介导的变化是由特异性mRNA的积累引起的酶合成的快速但短暂的诱导引起的。在菜豆下胚轴中也观察到类似的现象，即在不亲和和亲和的小种感染后开始合成植物抗毒素。Lindemuthianum。在菜豆中，L-苯丙氨酸解氨酶和查尔酮合酶都是由多基因家族编码的，在蛋白质水平上，它们都表现出亚基和完整酶的多态性。从激发子诱导的豆细胞的mRNA中产生了许多含有相同开放阅读框的小于全长的苯丙氨酸解氨酶拷贝DNA。苯丙氨酸解氨酶基因组克隆的分析预测不同氨基酸序列的酶形式的存在。在培养的豆细胞中，激发子差异诱导两个表观苯丙氨酸解氨酶同工酶具有最低的Km值。除了转录控制特定基因产物的出现外，翻译后过程还可能导致苯丙氨酸解氨酶亚基多态性增加，以及查尔酮异构酶的激活。内源性类苯丙素中间体库的变化可能表明苯丙氨酸解氨酶活性的快速去除，除了对编码苯丙氨酸解氨酶和其他植物抗毒素生物合成酶的mRNA的形成和/或活性产生较低的特异性抑制作用之外。
Treatment of cell suspension cultures of French bean (Phaseolus vulgaris) with polysaccharide elicitor molecules from cell walls of the anthracnose fungus, Colletotrichum lindemuthianum, results in the rapid accumulation of isoflavonoid phytoalexins, deposition of wall-bound phenolic compounds and synthesis of hydroxyproline-rich glycoproteins. These changes are dependent upon a highly selective induction of gene products, including the enzymes L-phenylalanine ammonia-lyase, cytochrome P450-dependent cinnamic acid 4-hydroxylase, chalcone synthase, chalcone isomerase, prolyl hydroxylase and protein: arabinosyl transferase. Use of in vivo labelling, in vitro translation and RNA blot hybridization techniques has shown that these elicitormediated changes arise from rapid but transient induction of enzyme synthesis, resulting from the accumulation of specific mRNAs. Similar phenomena are observed in bean hypocotyls at the onset of phytoalexin synthesis in response to infection by incompatible and compatible races of C. lindemuthianum. In bean, both L-phenylalanine ammonia-lyase and chalcone synthase are encoded by multigene families and, at the protein level, both exhibit subunit and intact enzyme polymorphism. A number of less than full-length phenylalanine ammonialyase copy DNAs containing identical open reading frames have been produced from mRNA from elicitor-induced bean cells. Analysis of phenylalanine ammonia-lyase genomic clones predicts the presence of enzyme forms of differing amino acid sequence. In cultured bean cells, elicitor differentially induces the two apparent phenylalanine ammonia-lyase iso-forms with the lowest Km values. In addition to transcriptional control of the appearance of specific gene products, post-translational processes may result in increased subunit polymorphism for phenylalanine ammonia-lyase, and in the activation of chalcone isomerase. Changes in endogenous phenylpropanoid intermediate pools may signal the rapid removal of phenylalanine ammonia-lyase activity, in addition to exerting less specific inhibitory effects on the formation and/or activity of the mRNAs encoding phenylalanine ammonia-lyase and other phytoalexin biosynthetic enzymes.