Nejamkin Andrés, Foresi Noelia, Mayta Martín L, Lodeyro Anabella F, Castello Fiorella Del, Correa-Aragunde Natalia, Carrillo Néstor, Lamattina Lorenzo
Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina.
Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
Front Plant Sci. 2020 Mar 20;11:312. doi: 10.3389/fpls.2020.00312. eCollection 2020.
Nitric oxide (NO) is a messenger molecule widespread studied in plant physiology. Latter evidence supports the lack of a NO-producing system involving a NO synthase (NOS) activity in higher plants. However, a NOS gene from the unicellular marine alga () was characterized in recent years. NOS is a genuine NOS, with similar spectroscopic fingerprints to mammalian NOSs and high NO producing capacity. We are interested in investigating whether OtNOS activity alters nitrogen metabolism and nitrogen availability, thus improving growth promotion conditions in tobacco. Tobacco plants were transformed with under the constitutive CaMV 35S promoter. Transgenic tobacco plants expressing accumulated higher NO levels compared to siblings transformed with the empty vector, and displayed accelerated growth in different media containing sufficient nitrogen availability. Under conditions of nitrogen scarcity, the growth promoting effect of the expression is diluted in terms of total leaf area, protein content and seed production. It is proposed that OtNOS might possess a plant growth promoting effect through facilitating N remobilization and nitrate assimilation with potential to improve crop plants performance.
一氧化氮（NO）是一种在植物生理学中得到广泛研究的信使分子。最近的证据表明高等植物中缺乏涉及一氧化氮合酶（NOS）活性的一氧化氮产生系统。然而，近年来已对单细胞海洋藻类（）中的一个NOS基因进行了表征。该NOS是一种真正的NOS，具有与哺乳动物NOS相似的光谱特征和高NO产生能力。我们有兴趣研究OtNOS活性是否会改变氮代谢和氮的有效性，从而改善烟草的生长促进条件。烟草植株在组成型CaMV 35S启动子的控制下用进行了转化。与用空载体转化的同胞相比，表达的转基因烟草植株积累了更高水平的NO，并在含有充足氮有效性的不同培养基中显示出加速生长。在氮缺乏的条件下，就总叶面积、蛋白质含量和种子产量而言，表达的生长促进作用被稀释。有人提出，OtNOS可能通过促进氮的再转运和硝酸盐同化而具有促进植物生长的作用，从而有可能提高作物的性能。
