Mitochondria use actin filaments as rails for fast translocation in Arabidopsis and tobacco cells
Mitochondria use actin filaments as rails for fast translocation in Arabidopsis and tobacco cells
复制标题
DOI：
10.5511/plantbiotechnology.24.441
复制
发表时间：
2007-12-01
影响因子：
1.6
通讯作者：
Tsutsumi, Nobuhiro
中科院分区：
文献类型：
--
作者：
Doniwa, Yoko;Arimura, Shin-ichi;Tsutsumi, Nobuhiro
虽然已知线粒体在植物细胞中活跃移动，但对它们如何移动知之甚少。据报道，在高等植物中，肌动蛋白丝参与细胞器的运动，如叶绿体、过氧化物酶体、内质网和高尔基体。利用与线粒体靶向信号融合的荧光蛋白，在活的拟南芥植物中观察线粒体。为了比较线粒体的运动和另一种细胞器的运动，我们还研究了过氧化物酶体，因为它们的大小相似。虽然两个细胞器的平均速度相似，但通过延时激光扫描显微镜测量的单个线粒体和过氧化物酶体的速度却有所不同。肌动蛋白解聚药物Latrunculin B阻止线粒体和过氧化物酶体的运动，表明这些细胞器的运动依赖于肌动蛋白丝。另一方面，微管解聚药物丙酰胺不影响线粒体和过氧化物酶体的运动。在活的拟南芥植物中，红色荧光蛋白显示线粒体或过氧化物酶体，绿色荧光蛋白同时显示细胞骨架元件，两个细胞器都使用肌动蛋白丝作为轨道移动。相反，它们的运动与微管阵列无关。我们还研究了烟草培养细胞的线粒体运动，同时观察线粒体和细胞骨架元件。线粒体常沿肌动蛋白丝运动，但不沿微管运动。这些发现表明，在高等植物中，线粒体沿着肌动蛋白丝快速而长距离地移动。
Although mitochondria are known to move actively in plant cells, little is known about how they move. In higher plants, actin filaments have been reported to be involved in the movement of organelles, such as chloroplasts, peroxisomes, endoplasmic reticulum and Golgi apparatus. Mitochondria were visualized in living Arabidopsis thaliana plants using fluorescent proteins fused to a mitochondria targeting signal. To compare the movement of mitochondria to the movements of another organelle, we also examined peroxisomes because of their similarity in size. Velocities of individual mitochondria and peroxisomes, as measured by time-lapse laser scanning microscopy, varied, although the average velocities of the two organelles were similar. Latrunculin B, an actin-depolymerizing drug, stopped movement of mitochondria and peroxisomes, demonstrating that movement of these organelles depends on actin filaments. On the other hand, propyzamide, a microtubule-depolymerizing drug, did not affect the movement of mitochondria and peroxisomes. In living Arabidopsis plants in which mitochondria or peroxisomes are visualized by red fluorescent protein and cytoskeletal elements are simultaneously visualized by green fluorescent protein, both organelles moved using actin filaments as rails. In contrast, their movement was not related to arrays of microtubules. We also examined mitochondrial movement in tobacco cultured cells visualizing mitochondria and cytoskeletal element simultaneously. Mitochondrial movement was often seen along actin filaments but not along microtubules. These findings suggest that mitochondria move along actin filaments rapidly and over long distances in higher plants.