Resmi Mohankumar Saraladevi, Vivek Padmanabhan Jayanthi, Soniya Eppurathu Vasudevan
Plant Molecular Biology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud (P.O.), Thiruvananthapuram 695 014, Kerala, India.
FEBS Lett. 2015 Jan 30;589(3):332-41. doi: 10.1016/j.febslet.2014.12.016. Epub 2014 Dec 30.
Type III polyketide synthases (PKSs) catalyze the biosynthesis of various medicinally important secondary metabolites in plants, but their role in growth and stress response is unclear. Here, we overexpressed quinolone synthase (QNS) from bael in tobacco. QNS-overexpressing plants showed an overall increase in growth, photosynthetic efficiency and chlorophyll content compared to wild type plants. Second-generation (T2) transgenic plants grew to maturity, flowered early and set viable seeds under favorable conditions without yield penalty. An increased accumulation of flavonoids, phenols and alkaloids was associated with higher tolerance to drought and salinity stress in transgenic plants. Thus, bael QNS seems to function as a positive regulator of plant growth and stress response, and could be potentially used for engineering plants tolerant to abiotic stress.
III型聚酮合酶（PKSs）催化植物中各种具有重要药用价值的次生代谢产物的生物合成，但其在生长和应激反应中的作用尚不清楚。在此，我们在烟草中过表达了来自印度枳椇的喹诺酮合酶（QNS）。与野生型植物相比，过表达QNS的植物在生长、光合效率和叶绿素含量方面总体有所增加。第二代（T2）转基因植物在有利条件下生长至成熟，开花早且能结出可育种子，而产量不受影响。转基因植物中黄酮类、酚类和生物碱的积累增加与对干旱和盐胁迫的更高耐受性相关。因此，印度枳椇QNS似乎作为植物生长和应激反应的正调控因子发挥作用，并且有可能用于培育耐受非生物胁迫的植物。
