Laboratory of Plant Cell Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
Plant Cell Physiol. 2011 Oct;52(10):1844-55. doi: 10.1093/pcp/pcr122. Epub 2011 Sep 4.
The actin cytoskeleton is involved in the transport and positioning of Golgi bodies, but the actin-based processes that determine the positioning and motility behavior of Golgi bodies are not well understood. In this work, we have studied the relationship between Golgi body motility behavior and actin organization in intercalary growing root epidermal cells during different developmental stages. We show that in these cells two distinct actin configurations are present, depending on the developmental stage. In small cells of the early root elongation zone, fine filamentous actin (F-actin) occupies the whole cell, including the cortex. In larger cells in the late elongation zone that have almost completed cell elongation, actin filament bundles are interspersed with areas containing this fine F-actin and areas without F-actin. Golgi bodies in areas with the fine F-actin exhibit a non-directional, wiggling type of motility. Golgi bodies in areas containing actin filament bundles move up to 7 μm s⁻¹. Since the motility of Golgi bodies changes when they enter an area with a different actin configuration, we conclude that the type of movement depends on the actin organization and not on the individual organelle. Our results show that the positioning of Golgi bodies depends on the local actin organization.
肌动蛋白细胞骨架参与高尔基体的运输和定位，但决定高尔基体定位和运动行为的基于肌动蛋白的过程还不是很清楚。在这项工作中，我们研究了在不同发育阶段的居间生长根表皮细胞中，高尔基体运动行为与肌动蛋白组织之间的关系。我们表明，在这些细胞中，存在两种不同的肌动蛋白构象，这取决于发育阶段。在早期根伸长区的小细胞中，细的丝状肌动蛋白（F-肌动蛋白）占据整个细胞，包括皮层。在伸长区后期的较大细胞中，细胞伸长几乎完成，肌动蛋白丝束与含有这种细 F-肌动蛋白的区域和不含 F-肌动蛋白的区域交错。在含有细 F-肌动蛋白的区域中，高尔基体表现出非定向的、扭动的运动类型。含有肌动蛋白丝束的高尔基体的运动速度可达 7 μm s⁻¹。由于高尔基体进入不同肌动蛋白构象的区域时其运动方式发生变化，我们得出结论，运动类型取决于肌动蛋白组织，而不是单个细胞器。我们的结果表明，高尔基体的定位取决于局部肌动蛋白组织。
