Amyloplasts and vacuolar membrane dynamics in the living graviperceptive cell of the Arabidopsis inflorescence stem
Amyloplasts and vacuolar membrane dynamics in the living graviperceptive cell of the Arabidopsis inflorescence stem
复制标题
DOI：
10.1105/tpc.104.026138
复制
发表时间：
2005-02-01
期刊：
影响因子：
11.6
通讯作者：
Tasaka, M
中科院分区：
文献类型：
--
作者：
Saito, C;Morita, MT;Tasaka, M
我们开发了一种适当的方法，在体内分析的重力感知细胞（内皮）的拟南芥花序干的细胞器动态，揭示在这些细胞中的淀粉体和液泡膜的行为。内皮层中的淀粉体甚至在重力刺激之前通过重定向显示跳跃运动，并且这些运动被证实为微丝依赖的。从我们在野生型的定量分析，重力定向运动的淀粉体主要发生在0至3分钟后重力刺激重定向，支持我们以前的生理研究结果。即使在微丝断裂后，淀粉体的重力定向运动仍然存在。相比之下，在zig/sgr 4突变体中，其中在液泡生物发生中起作用的SNARE分子被破坏，内皮层中的淀粉体的运动在重力刺激之前和之后通过重定向都受到严重限制。在这里，我们描述了空泡膜行为在这些细胞中的野生型，肌动蛋白破坏，zig/sgr 4突变体和讨论其pusimonary重要功能的感知重力。我们还讨论了在向重力性中可能起重要作用的两种造粉体运动：（1）造粉体的前缘运动和（2）造粉体的整体运动。
We developed an adequate method for the in vivo analysis of organelle dynamics in the gravity-perceptive cell (endodermis) of the Arabidopsis thaliana inflorescence stem, revealing behavior of amyloplasts and vacuolar membranes in those cells. Amyloplasts in the endodermis showed saltatory movements even before gravistimulation by reorientation, and these movements were confirmed as microfilament dependent. From our quantitative analysis in the wild type, the gravity-oriented movement of amyloplasts mainly occurred during 0 to 3 min after gravistimulation by reorientation, supporting findings from our previous physiological study. Even after microfilament disruption, the gravity-oriented movement of amyloplasts remained. By contrast, in zig/sgr4 mutants, where a SNARE molecule functioning in vacuole biogenesis has been disrupted, the movement of amyloplasts in the endodermis is severely restricted both before and after gravistimulation by reorientation. Here, we describe vacuolar membrane behavior in these cells in the wild-type, actin filament-disrupted, and zig/sgr4 mutants and discuss its putatively important features for the perception of gravity. We also discuss the data on the two kinds of movements of amyloplasts that may play an important role in gravitropism: (1) the leading edge amyloplasts and (2) the en mass movement of amyloplasts.