Yokotani Naoki, Ichikawa Takanari, Kondou Youichi, Matsui Minami, Hirochika Hirohiko, Iwabuchi Masaki, Oda Kenji
Research Institute for Biological Sciences, Okayama, 7549-1 Yoshikawa, Kibichuo-cho, Okayama 716-1241, Japan.
Planta. 2009 Apr;229(5):1065-75. doi: 10.1007/s00425-009-0895-5. Epub 2009 Feb 19.
Environmental stresses limit plant growth and crop production worldwide. We attempted to isolate rice genes involved in conferring tolerance to environmental stresses by using a transgenic Arabidopsis population expressing full-length cDNAs of rice. Among these lines, a thermotolerant line, R08946, was detected. The rice cDNA inserted in R08946 encoded a NAC transcription factor, ONAC063. This protein was localized in the nucleus and showed transactivation activity at the C-terminus. ONAC063 expression was not induced by high-temperature but highly induced by high-salinity in rice roots. High-osmotic pressure and reactive oxygen species levels also induced ONAC063 expression. The seeds of ONAC063-expressing transgenic Arabidopsis showed enhanced tolerance to high-salinity and osmotic pressure. Microarray and real-time reverse transcription-polymerase chain reaction analyses showed upregulated expression of some salinity-inducible genes, including the amylase gene AMY1, in ONAC063-expressing transgenic Arabidopsis. Thus, ONAC063 may play an important role in eliciting responses to high-salinity stress.
环境胁迫限制了全球范围内的植物生长和作物产量。我们试图通过使用一个表达水稻全长cDNA的转基因拟南芥群体来分离参与赋予植物对环境胁迫耐受性的水稻基因。在这些株系中，检测到了一个耐热株系R08946。插入R08946中的水稻cDNA编码一个NAC转录因子ONAC063。该蛋白定位于细胞核，且在其C端显示出反式激活活性。在水稻根中，ONAC063的表达不受高温诱导，但受高盐强烈诱导。高渗透压和活性氧水平也诱导ONAC063的表达。表达ONAC063的转基因拟南芥种子对高盐和渗透压的耐受性增强。基因芯片和实时逆转录-聚合酶链反应分析表明，在表达ONAC063的转基因拟南芥中，一些盐诱导基因，包括淀粉酶基因AMY1的表达上调。因此，ONAC063可能在引发对高盐胁迫的反应中起重要作用。
