Department of Agricultural Sciences, Faculty of Sciences, Allama Iqbal Open University, Islamabad, Pakistan.
National Institute for Genomics & Advanced Biotechnology (NIGAB), National Agricultural Research Centre (NARC), Islamabad, Pakistan.
Environ Sci Pollut Res Int. 2017 Aug;24(22):18536-18553. doi: 10.1007/s11356-017-9460-0. Epub 2017 Jun 23.
Plants integrate and monitor low temperature signals to cope with the continual variations in their environment. Arabidopsis thaliana cold responsive-element binding factor 3 (AtCBF3) plays its role in various cellular activities by modulating multiple genes induced under chilling stress. In this work, AtCBF3 transcription was remarkably induced following chilling stress. AtCBF3-overexpressors namely AtCBF3-Rio Grande, AtCBF3-Moneymaker, and AtCBF3-Roma showed defensible response to various levels of chilling stress, while their isogenic wild type plants indicated hypersensitive response to chilling stress. Detailed photosynthetic studies revealed that AtCBF3 gene has harmonious influences on the expression of a large set of genes by virtue of improved stomatal conductance, transpiration rate, intercellular CO concentration, and photosynthetic rate compared to wild type plants. The AtCBF3 lines limited the water status-mediated hypersensitive response by lowering leaf osmotic potential due to overexpression of AtCBF3 under chilling stress. Biochemical analyses followed by phenotypic studies demonstrated that AtCBF3 plants exhibited membrane stability and lush green appearance by limiting membrane ions leakage and malondialdehyde contents and by accumulating more proline, soluble sugars, chlorophyll contents, carotenoid contents, and antioxidant enzymes relative to wild type plants. Hence, with a several lines of evidence, these findings support that tomato transgenic plants overexpressing Arabidopsis CBF3 show enhanced chilling tolerance.
植物整合和监测低温信号，以应对环境的持续变化。拟南芥冷响应元件结合因子 3（AtCBF3）通过调节在冷胁迫下诱导的多个基因，在各种细胞活动中发挥作用。在这项工作中，AtCBF3 在受到冷胁迫后显著诱导转录。AtCBF3 过表达株系，即 AtCBF3-Rio Grande、AtCBF3-Moneymaker 和 AtCBF3-Roma，对各种程度的冷胁迫表现出防御性反应，而其同型野生型植物对冷胁迫表现出超敏反应。详细的光合作用研究表明，AtCBF3 基因通过提高气孔导度、蒸腾速率、胞间 CO2 浓度和光合速率，对大量基因的表达具有协调影响，与野生型植物相比。AtCBF3 系通过在冷胁迫下过表达 AtCBF3 降低叶片渗透势，限制由水分状态介导的超敏反应。生化分析和表型研究表明，AtCBF3 植物通过限制膜离子泄漏和丙二醛含量，积累更多脯氨酸、可溶性糖、叶绿素含量、类胡萝卜素含量和抗氧化酶，表现出膜稳定性和郁郁葱葱的绿色外观，与野生型植物相比。因此，有几项证据支持番茄转基因植物过表达拟南芥 CBF3 表现出增强的耐冷性。
