Coordinated regulation of genes for secretion in tobacco at late developmental stages:: Association with resistance against oomycetes
Coordinated regulation of genes for secretion in tobacco at late developmental stages:: Association with resistance against oomycetes
复制标题
DOI：
10.1104/pp.103.034173
复制
发表时间：
2004-02-01
期刊：
影响因子：
7.4
通讯作者：
Galiana, E
中科院分区：
文献类型：
--
作者：
Hugot, K;Rivière, MP;Galiana, E
除了对微生物刺激产生的系统获得性抗性（SAR）外，寄主植物还可能对与自身发育相关的内源刺激产生抗性。在烟草（Nicotiana tabacum）中，从植物到开花的转变沿着着对黑胫病病原体卵菌寄生疫霉（Phytophthora parasitica）的易感性到抗性的转变。这种抗性影响感染有效性和菌丝扩张，并且与引起寄生疫霉游动孢子的体外细胞死亡的细胞毒性活性的细胞外积累相关。作为确定限制病原体生长的重要细胞外事件的策略，我们筛选了烟草基因组中编码在开花植物叶片中表达的分泌或膜结合蛋白的基因。使用信号序列陷阱的方法在酵母（酿酒酵母），298个克隆被选中，似乎编码质外体，细胞壁，或膜结合蛋白参与胁迫反应，在植物防御，或在细胞壁修饰。微阵列和Northern印迹分析表明，在发育后期，叶的特点是参与SAR和过氧化交联的结构蛋白到细胞壁的基因的协调上调。这表明这些基因可能参与控制发育抗性表达的细胞外事件。水杨酸对mRNA积累的影响的分析还表明，在烟草发育的后期阶段，比在SAR期间，基因表达的调控网络更复杂。这些基因的进一步特征将允许制定的假设来解释阻力，并建立与发展的联系。
Besides the systemic acquired resistance (SAR) induced in response to microbial stimulation, host plants may also acquire resistance to pathogens in response to endogenous stimuli associated with their own development. In tobacco (Nicotiana tabacum), the vegetative-to-flowering transition comes along with a susceptibility-to-resistance transition to the causal agent of black shank disease, the oomycete Phytophthora parasitica. This resistance affects infection effectiveness and hyphal expansion and is associated with extracellular accumulation of a cytotoxic activity that provokes in vitro cell death of P. parasitica zoospores. As a strategy to determine the extracellular events important for restriction of pathogen growth, we screened the tobacco genome for genes encoding secreted or membrane-bound proteins expressed in leaves of flowering plants. Using a signal sequence trap approach in yeast (Saccharomyces cerevisiae), 298 clones were selected that appear to encode for apoplastic, cell wall, or membrane-bound proteins involved in stress response, in plant defense, or in cell wall modifications. Microarray and northern-blot analyses revealed that, at late developmental stages, leaves were characterized by the coordinate up-regulation of genes involved in SAR and in peroxidative cross-linking of structural proteins to cell wall. This suggests the potential involvement of these genes in extracellular events that govern the expression of developmental resistance. The analysis of the influence of salicylic acid on mRNA accumulation also indicates a more complex network for regulation of gene expression at a later stage of tobacco development than during SAR. Further characterization of these genes will permit the formulation of hypotheses to explain resistance and to establish the connection with development.