ABA和NO信号对UV-B胁迫下大豆芽菜中异黄酮合成的作用机制

Medium wave of ultraviolet (UV-B) radiation could induce isoflavone accumulation in soybean sprouts. Abscisic acid (ABA) and nitric oxide (NO) were involved in isoflavone accumulation. However, the mechanism is still not clear. The proposed study will systematically investigate ABA and NO signals as well as their interactions on isoflavone biosynthesis and accumulation in soybean sprouts under UV-B stress. Simultaneously, the downstream biomessengers such as cGMP, cADPR and IP3, induced by ABA and NO, and their roles in isoflavone accumulation will also be explored for better understanding the existence of PKG, a target molecule of cGMP, and its role in further induction of cADPR and IP3. Finally, the induction of Ca2+ by UV-B radiation and its involvement in isoflavone accumulation will scientifically reveal functions of the second biomessengers of cGMP, cADPR and IP3. The objectives of this study are to comprehensively investigate the role of network in interactive signaling pathways consisting of ABA and NO and their possible downstream messengers of cGMP, cADPR, IP3 and Ca2+ as well for UV-B-induced isoflavone biosnthesis and accumulation in soybean sprouts at a deep level of enzymatic and molecular mechanisms.

中波紫外光（Medium wave of ultraviolet, UV-B）胁迫可诱导大豆芽菜异黄酮的累积，脱落酸（Abscisic acid, ABA）和一氧化氮（Nitric oxide, NO）信号参与其合成，但其作用机制尚不明确。针对这一科学问题，本项目研究UV-B胁迫下ABA和NO促进大豆芽菜生物合成和累积异黄酮的介导与交互作用、及其对次级信号分子cGMP、cADPR和IP3的诱导作用和机理，探索cGMP作用的受体PKG对cADPR和IP3、以及UV-B对Ca2+的诱导作用和作为cGMP、cADPR及IP3的次级信号转导ABA和NO生物信号在异黄酮合成中的作用，揭示ABA、NO、cGMP、cADPR、IP3、PKG及Ca2+对异黄酮合成关键酶基因的调控效应及组成的网络交互信号通路，从分子水平上揭示UV-B对异黄酮富集的调控的生物信号转导机制。