Waseem Muhammad, Rong Xiangyi, Li Zhengguo
Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing, China.
Front Plant Sci. 2019 Jun 4;10:734. doi: 10.3389/fpls.2019.00734. eCollection 2019.
Environmental stresses, such as temperature, heavy metals, drought, cold, and microbial infections adversely damage various aspects of plant growth and development. Salinity and drought are among major hazardous factors, which adversity affects plant growth and productivity. Transcription factors, such as basic helix-loop-helix play critical roles in regulating plant physiological processes under abiotic stresses. In this study, we presented the characterization of a tomato gene under abiotic stresses such as drought and salinity. Plants overexpressing showed short height with small leaves and enhanced flavonoid accumulation. In wild type (WT) plant, the elevated levels of were detected under salt and D-mannitol stresses. Subcellular localization analysis revealed that protein was targeted to the nucleus in onion epidermal cells. Transactivation assay in yeast demonstrated that had transcriptional activation ability. The transgenic plants overexpressing displayed enhanced vigor and more tolerant to drought and salinity than WT. Overexpression of significantly peaked the activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) to minimize the impacts of reactive oxygen species such as HO, which was reduced significantly in transgenic plants along with Malondialdehyde (MDA). Moreover, the expression levels of ROS defense genes (), ABA biosynthesis genes, proline biosynthesis, and flavonoids synthesis genes were also activated under salinity and drought. Taken together, our study implies that the overexpression of improved tomato plant stress resistance by improving ROS scavenging system, increasing osmotic potential and enhanced accumulation of secondary metabolites in tomato plants.
环境胁迫,如温度、重金属、干旱、寒冷和微生物感染,会对植物生长发育的各个方面造成不利损害。盐度和干旱是主要的有害因素,逆境会影响植物生长和生产力。转录因子,如碱性螺旋-环-螺旋,在非生物胁迫下调节植物生理过程中起关键作用。在本研究中,我们展示了一个番茄基因在干旱和盐度等非生物胁迫下的特征。过表达该基因的植株株高较矮,叶片较小,类黄酮积累增加。在野生型(WT)植株中,在盐胁迫和D-甘露醇胁迫下检测到该基因水平升高。亚细胞定位分析表明,该蛋白在洋葱表皮细胞中定位于细胞核。酵母中的反式激活分析表明,该基因具有转录激活能力。过表达该基因的转基因植株比野生型表现出更强的活力,对干旱和盐度更耐受。过表达该基因显著提高了过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和过氧化物酶(POD)的活性,以最小化活性氧如HO的影响,转基因植株中的HO以及丙二醛(MDA)显著降低。此外,在盐度和干旱条件下,ROS防御基因、ABA生物合成基因、脯氨酸生物合成基因和类黄酮合成基因的表达水平也被激活。综上所述,我们的研究表明,该基因的过表达通过改善番茄植株的ROS清除系统、增加渗透势和增强次生代谢产物积累来提高番茄植株的抗逆性。