Frese M, Prins M, Ponten A, Goldbach R W, Haller O, Zeltz P
Abteilung Virologie, Institut für Medizinische Mikrobiologie und Hygiene, Universität Freiburg, Germany.
Transgenic Res. 2000 Dec;9(6):429-38. doi: 10.1023/a:1026526314875.
MxA is a key component in the interferon-induced antiviral defense in humans. After viral infections, MxA is rapidly induced and accumulates in the cytoplasm. The multiplication of many RNA viruses, including all bunyaviruses tested so far, is inhibited by MxA. These findings prompted us to express MxA in plants in an attempt to create resistance to tospoviruses. Here, we report the generation of transgenic tobacco plants that constitutively express MxA under the control of the 35 S cauliflower mosaic virus promotor. Northern and western blot analysis confirmed the expression of MxA in several transgenic plant lines. MxA expression had no obvious detrimental effects on plant growth and fertility. However, challenge experiments with tomato spotted wilt virus, tomato chlorotic spot virus, and groundnut ringspot virus revealed no increased resistance of MxA-transgenic tobacco plants to tospovirus infections. Neither was the multiplication of tobacco mosaic virus, cucumber mosaic virus and potato virus Y inhibited in MxA-transgenic plants. The results indicate that the expression of human MxA alone does not enhance virus resistance in planta.
MxA是人类干扰素诱导的抗病毒防御中的关键成分。病毒感染后，MxA会迅速被诱导并在细胞质中积累。许多RNA病毒的增殖，包括迄今为止测试的所有布尼亚病毒，都受到MxA的抑制。这些发现促使我们在植物中表达MxA，试图创造对番茄斑萎病毒属病毒的抗性。在此，我们报告了在35S花椰菜花叶病毒启动子控制下组成型表达MxA的转基因烟草植株的产生。Northern印迹和Western印迹分析证实了MxA在几个转基因植物系中的表达。MxA的表达对植物生长和育性没有明显的有害影响。然而，用番茄斑萎病毒、番茄褪绿斑病毒和花生环斑病毒进行的挑战实验表明，MxA转基因烟草植株对番茄斑萎病毒属病毒感染的抗性没有增加。在MxA转基因植物中，烟草花叶病毒、黄瓜花叶病毒和马铃薯Y病毒的增殖也没有受到抑制。结果表明，单独表达人MxA并不能增强植物对病毒的抗性。
