Seo Pil Joon, Park Chung-Mo
Molecular Signaling Laboratory, Department of Chemistry, Seoul National University, Seoul Korea.
Molecular Signaling Laboratory, Department of Chemistry, Seoul National University.
Plant Signal Behav. 2010 May;5(5):481-3. doi: 10.4161/psb.11083. Epub 2010 Feb 8.
Transcription factors are central components of gene regulatory networks that mediate virtually all aspects of growth and developmental processes in biological systems. The activity of transcription factors is regulated at multiple steps, such as gene transcription, posttranscriptional RNA processing, posttranslational modification, protein-protein interactions, and controlled protein turnover. Controlled activation of dormant, membrane-bound transcription factor (MTF) is an intriguing regulatory mechanism that ensures quick transcriptional responses to environmental fluctuations in plants, in which various stress hormones serve as signaling mediators. NTL6 is proteolytically activated upon exposure to cold and induces expression of the Pathogenesis-Related (PR) genes. The membrane-mediated cold signaling in inducing pathogen resistance is considered to be an adaptive strategy that protects plants against infection by hydrophilic pathogens frequently occurring during cold season. We found that NTL6 also mediates abscisic acid (ABA) regulation of abiotic stress responses in Arabidopsis. NTL6 is proteolytically activated by ABA. Transgenic plants overexpressing a nuclear NTL6 form (35S:6ΔC) exhibited a hypersensitive response to ABA and high salinity in seed germination. Taken together, these observations indicate that NTL6 plays an integrative role in plant responses to both biotic and abiotic stress conditions.
转录因子是基因调控网络的核心组成部分，几乎介导了生物系统中生长和发育过程的所有方面。转录因子的活性在多个步骤受到调控，如基因转录、转录后RNA加工、翻译后修饰、蛋白质-蛋白质相互作用以及可控的蛋白质周转。休眠的膜结合转录因子（MTF）的可控激活是一种有趣的调控机制，可确保植物对环境波动做出快速转录反应，其中各种应激激素充当信号介质。NTL6在暴露于低温时被蛋白水解激活，并诱导病程相关（PR）基因的表达。诱导病原体抗性的膜介导的冷信号被认为是一种适应性策略，可保护植物免受寒冷季节频繁出现的亲水性病原体的感染。我们发现NTL6还介导拟南芥中脱落酸（ABA）对非生物胁迫反应的调控。NTL6被ABA蛋白水解激活。过表达核NTL6形式（35S:6ΔC）的转基因植物在种子萌发中对ABA和高盐度表现出超敏反应。综上所述，这些观察结果表明NTL6在植物对生物和非生物胁迫条件的反应中发挥着综合作用。
