Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China University of Chinese Academy of Sciences, Beijing, 100039, China.
J Exp Bot. 2014 Aug;65(15):4119-31. doi: 10.1093/jxb/eru184. Epub 2014 May 27.
Nitric oxide (NO) is involved in plant responses to many environmental stresses. Transgenic Arabidopsis lines that constitutively express rat neuronal NO synthase (nNOS) were described recently. In this study, it is reported that the nNOS transgenic Arabidopsis plants displayed high levels of osmolytes and increased antioxidant enzyme activities. Transcriptomic analysis identified 601 or 510 genes that were differentially expressed as a consequence of drought stress or nNOS transformation, respectively. Pathway and gene ontology (GO) term enrichment analyses revealed that genes involved in photosynthesis, redox, stress, and phytohormone and secondary metabolism were greatly affected by the nNOS transgene. Several CBF genes and members of zinc finger gene families, which are known to regulate transcription in the stress response, were changed by the nNOS transgene. Genes regulated by both the nNOS transgene and abscisic acid (ABA) treatments were compared and identified, including those for two ABA receptors (AtPYL4 and AtPYL5). Moreover, overexpression of AtPYL4 and AtPYL5 enhanced drought resistance, antioxidant enzyme activity, and osmolyte levels. These observations increase our understanding of the role of NO in drought stress response in Arabidopsis.
一氧化氮（NO）参与植物对许多环境胁迫的响应。最近描述了组成型表达大鼠神经元型一氧化氮合酶（nNOS）的转基因拟南芥系。在这项研究中，据报道，nNOS 转基因拟南芥植物表现出高水平的渗透物和增加的抗氧化酶活性。转录组分析确定了 601 或 510 个基因，分别由于干旱胁迫或 nNOS 转化而差异表达。途径和基因本体（GO）术语富集分析表明，参与光合作用、氧化还原、胁迫以及植物激素和次生代谢的基因受到 nNOS 转基因的极大影响。一些 CBF 基因和锌指基因家族的成员，已知它们在应激反应中调节转录，被 nNOS 转基因改变。比较并鉴定了受 nNOS 转基因和脱落酸（ABA）处理调节的基因，包括两个 ABA 受体（AtPYL4 和 AtPYL5）。此外，AtPYL4 和 AtPYL5 的过表达增强了抗旱性、抗氧化酶活性和渗透物水平。这些观察结果增加了我们对 NO 在拟南芥干旱胁迫响应中的作用的理解。
