HaNAC2转基因烟草响应干旱和高温胁迫的分子机制

The Molecular Mechanism of HaNAC2 Transgenic Tobacco Response to Drought and High Temperature Stresses

为了解析HaNAC2基因介导的梭梭抗逆分子机制,本研究通过酵母杂交技术分析HaNAC2蛋白的激活活性及二聚体的形成,并对HaNAC2转基因烟草在高温和干旱胁迫下的生理指标进行测定和分析。结果表明HaNAC2在酵母中不具有转录激活活性,且不能够形成同源二聚体;与非转基因烟草相比,HaNAC2转基因烟草在高温和干旱胁迫下受到的伤害更小,且干旱胁迫后的根系比野生型发达;转基因烟草根系干旱胁迫后,苯丙素生物合成和碳代谢途径中上调的差异基因数量最多,叶片高温胁迫后苯丙素生物合成和淀粉蔗糖代谢通路中上调的差异基因数量最多。综上所述,HaNAC2蛋白可能通过与其他蛋白互作的形式参与到木质素的生物合成过程中,进而使植株能够抵御干旱和高温胁迫,研究结果为明确梭梭HaNAC2转录因子的抗逆分子机制提供参考。

In order to analyze the molecular mechanism of stress resistance of related genes specifically expressed in Haloxylon ammodendron under stress conditions,analysis of HaNAC2 protein activation and dimer formation by yeast hybridization,and the physiological indexes of HaNAC2 transgenic tobacco under high temperature and drought stress were measured and analyzed by RNA-seq technology.The results showed that HaNAC2 had no transcriptional activation activity in yeast and could not form homodimers.Under high temperature and drought stress,HaNAC2 transgenic tobacco has less damage and stronger resistance to high temperature and drought stress than non-transgenic tobacco.The roots of HaNA C2 transgenic tobacco were more developed than those of wild type under drought stress.The number of up-regulated genes in phenylpropanoid biosynthesis and carbon metabolism pathway was the largest after drought stress in transgenic tobacco roots,and the number of up-regulated genes in phenylpropanoid biosynthesis and starch sucrose metabolism pathway was the largest after high temperature stress in leaves.In summary,HaNAC2 protein may participate in the biosynthesis of lignin by interacting with other proteins,so that plants can withstand drought and high temperature stress.The results lay a theoretical foundation for clarifying the molecular mechanism of stress resistance of HaNAC2 transcription factors in Haloxylon ammodendron.