Microtubule-Dependent Confinement of a Cell Signaling and Actin Polymerization Control Module Regulates Polarized Cell Growth
Microtubule-Dependent Confinement of a Cell Signaling and Actin Polymerization Control Module Regulates Polarized Cell Growth
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DOI：
10.1016/j.cub.2018.05.076
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发表时间：
2018-08
期刊：
影响因子：
9.2
通讯作者：
M. Yanagisawa;J. Alonso;D. Szymanski
中科院分区：
文献类型：
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作者：
M. Yanagisawa;J. Alonso;D. Szymanski
具有广泛变化的形状的细胞类型使用许多相同的信号传导和细胞骨架蛋白来动态地形成其几何形状[1-3]。植物细胞被包裹在坚韧的细胞外壁中，生长模式间接受细胞骨架及其局部指定壁的材料性质的能力控制[4，5]。肌动蛋白和微管的广泛和不重叠的结构域被预测会产生具有独特机械特性的尖锐细胞壁边界[6]，这些特性通常被提出来指导生长模式和细胞形状[1，6，7]。然而，细胞骨架在决定细胞形态的空间和时间尺度上形成图案的机制尚不清楚。在这里，我们使用活细胞成像探针和独特的形态突变体inclusionopsis的组合，以发现如何微管和肌动蛋白系统在空间上协调模式极化生长在叶表皮细胞。DOCK家族鸟嘌呤核苷酸交换因子（GEF）SPIKE 1 [8，9]聚集并激活细胞顶端的保守异聚WAVE/SCAR和ARP 2/3复合物，以产生有组织的肌动蛋白网络，定义一般的细胞质流动模式。皮质微管围栏点状SPIKE 1信号结节和限制肌动蛋白聚合在一个广泛的微管耗尽区在细胞顶端。我们的数据提供了一个有用的模型，细胞形状控制，其中全球环境基金，肌动蛋白丝成核复合物，微管，和细胞壁的功能作为相互作用的系统，动态模式极化生长。
Cell types with wildly varying shapes use many of the same signaling and cytoskeletal proteins to dynamically pattern their geometry [1–3]. Plant cells are encased in a tough outer cell wall, and growth patterns are indirectly controlled by the cytoskeleton and its ability to locally specify the material properties of the wall [4, 5]. Broad and non-overlapping domains of actin and microtubules are predicted to create sharp cell-wall boundaries with distinct mechanical properties [6] that are often proposed to direct growth patterns and cell shape [1, 6, 7]. However, mechanisms by which the cytoskeleton is patterned at the spatial and temporal scales that dictate cell morphology are not known. Here, we used combinations of live-cell imaging probes and unique morphology mutants inArabidopsisto discover how the microtubule and actin systems are spatially coordinated to pattern polarized growth in leaf epidermal cells. The DOCK family guanine nucleotide exchange factor (GEF) SPIKE1 [8, 9] clusters and activates conserved heteromeric WAVE/SCAR and ARP2/3 complexes at the cell apex to generate organized actin networks that define general cytoplasmic flow patterns. Cortical microtubules corral punctate SPIKE1 signaling nodules and restrict actin polymerization within a broad microtubule-depletion zone at the cell apex. Our data provide a useful model for cell-shape control, in which a GEF, actin filament nucleation complexes, microtubules, and the cell wall function as interacting systems that dynamically pattern polarized growth.