Unstable F-actin specifies the area and microtubule direction of cell expansion in Arabidopsis root hairs
Unstable F-actin specifies the area and microtubule direction of cell expansion in Arabidopsis root hairs
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DOI：
10.1105/tpc.007039
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发表时间：
2003-01-01
期刊：
影响因子：
11.6
通讯作者：
Emons, AMC
中科院分区：
文献类型：
--
作者：
Ketelaar, T;de Ruijter, NCA;Emons, AMC
植物细胞通过吐出高尔基体小泡中所含的壁材来扩张。我们研究了肌动蛋白细胞骨架的局部不稳定性在确定拟南芥根毛胞吞作用部位中的作用。在根毛生长过程中，细胞的近顶端存在一种特殊的肌动蛋白细胞骨架构型，它由细束的肌动蛋白细丝组成，这些细丝向顶端变得越来越细，在顶端可能不存在。脉冲应用低浓度的肌动蛋白解聚药物细胞松弛素D和乳头状菌素A可使正在生长的根毛尖端变宽(即它们增加了细胞扩张的面积)。有趣的是，细胞松弛素D的恢复导致了原生长方向的新生长，而在微管解聚药物oryzalin的存在下，这个方向被改变了。在相同浓度下，单独使用oryzalin对根毛伸长没有影响。这些结果代表了理解根毛生长的空间和方向调节的重要一步。
Plant cells expand by exocytosis of wall material contained in Golgi-derived vesicles. We examined the role of local instability of the actin cytoskeleton in specifying the exocytosis site in Arabidopsis root hairs. During root hair growth, a specific actin cytoskeleton configuration is present in the cell's subapex, which consists of fine bundles of actin filaments that become more and more fine toward the apex, where they may be absent. Pulse application of low concentrations of the actin-depolymerizing drugs cytochalasin D and latrunculin A broadened growing root hair tips (i.e., they increased the area of cell expansion). Interestingly, recovery from cytochalasin D led to new growth in the original growth direction, whereas in the presence of oryzalin, a microtubule-depolymerizing drug, this direction was altered. Oryzalin alone, at the same concentration, had no influence on root hair elongation. These results represent an important step toward understanding the spatial and directional regulation of root hair growth.