Study on Male Sterility of Plants by Direct Transfer of Mitochondria and mitochondrial DNA

粒子轰击已被先前的作者（例如，Svab等）证明是一种强大的细胞器转化方法。Pnas 87:, 8526-8530, 1990)。在这项研究中，我们开发了自己的粒子枪装置，并试图转化高等植物的线粒体。我们还没有成功地改造线粒体。然而，我们获得了一些基本的结果，这些结果将对未来的细胞器转化研究有用。我们开发了由氮气压力和压缩空气压力驱动的粒子枪装置。氮气压力驱动装置的最大加速压力（即用于加速塑料弹丸的压力）为25 kg/cm^2，而气动颗粒枪装置的最大加速压力大于220 kg/cm^2。采用气动颗粒枪时，弹丸最大速度可达440 m/s以上。利用这些装置，我们已经证明质粒DNA可以成功导入，并且引入的外源基因（如GUSgene）可以在完整的组织以及各种植物的培养细胞中成功表达，如烟草、大豆和拟南芥（dicots）以及水稻和小麦（mono子叶）。我们利用这两种粒子枪装置成功地稳定转化了烟草NPTII基因培养细胞。我们还将NPTII基因传递到拟南芥的根细胞和卡那霉素抗性芽中。在卡那霉素的作用下，所选的芽成功地发育成完整的植株（迄今已获得20多株这样的植株）并结实子。

Particle bombardment has been shown to be a powerful method for the transformation of organelles by the previous authors (e. g., Svab et al. PNAS 87 : , 8526-8530, 1990). In this study we developed our own particle gun device and attempted to transform mitochondria of higher plants. We have not yet succeeded in transformation of mitodondria. However, we obtained some fundamental results that will be useful for studies on organeLle transformation in future.1. We have developed particle gun devices that are driven by nitrogen gas pressure and compressed air pressure. Nitrogen-gas-pressure-driven device had a maximum accelerating pressure (i. e. pressure that was used to accelerate plastic projectiles) of 25 kg/cm^2, while pneumatic particle gun device had a maximum accelerating pressure of more than 220 kg/cm^2. With the pneumatic particle gun, the maximum velocity of projectile was more than 440 m/s.2. Using these devices, we have shown that plasmid DNA can successfully be introduced and the introduced foreign genes (e. g. GUSgene) can successfully be expressed in intact tissues as well ascultured cells of various plants such as tobacco, soybean and Arabidopsis (dicots) and rice and wheat (monocots).3. We succeeded in stable transformation of cultured cells of tobacco with NPTII gene by use of these two particle gun devices. We also delivered the NPTII gene into root cells of Arabidopsis and selected kanamycin-resistant shoots. The selected shoots successfully developed into complete plants (more than 20 such plants have so far been obtained) in the presence of kanamycin and set seeds.