Mapping the growth of fungal hyphae:: Orthogonal cell wall expansion during tip growth and the role of turgor
Mapping the growth of fungal hyphae:: Orthogonal cell wall expansion during tip growth and the role of turgor
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DOI：
10.1016/s0006-3495(00)76483-6
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发表时间：
2000-11-01
影响因子：
3.4
通讯作者：
Lu, HS
中科院分区：
文献类型：
--
作者：
Bartnicki-Garcia, S;Bracker, CE;Lu, HS
通过计算机增强的视频显微镜，绘制了真菌菌丝生长过程中细胞内外表面标记物的轨迹，以确定根尖生长过程中细胞壁的扩增模式，并选择碳颗粒（墨汁）作为外源标记物，对茄根丝胞菌菌丝的尖端扩增进行了研究。荆芥生长顶壁的不规则性作为内部标记。在从录像序列中捕获的帧中跟踪标记的运动。外部和内部标记均遵循正交轨迹；即，它们垂直于细胞表面移动，而不管它们在菌丝顶端的初始位置。我们发现没有证据表明尖端旋转在伸长。生长菌丝的细胞壁呈正交扩张的发现在两个方面产生了重大影响：1)它支持了长期以来的观点，即胀压是推动细胞壁扩张的主要力量。2)为完成基于囊泡供应中心概念的菌丝形态发生三维模型的数学推导提供了重要信息。在三维空间中，由囊泡供应中心产生的囊泡梯度不足以解释形状；还需要知道在墙体膨胀过程中现有表面位移的方式。
By computer-enhanced videomicroscopy, we mapped the trajectory of external and internal cell surface markers in growing fungal hyphae to determine the pattern of cell wall expansion during apical growth, Carbon particles (India ink) were chosen as external markers for tip expansion of Rhizoctonia solani hyphae. Irregularities in the growing apical walls of R. solani sewed as internal markers. Marker movement was traced in captured frames from the videotaped sequences. External and internal markers both followed orthogonal trajectories; i.e., they moved perpendicular to the cell surface regardless of their initial position in the hyphal apex. We found no evidence that the tip rotates during elongation. The discovery that the cell wall of a growing hypha expands orthogonally has major repercussions on two fronts: 1) It supports the long-held view that turgor pressure is the main force driving cell wall expansion. 2) It provides crucial information to complete the mathematical derivation of a three-dimensional model of hyphal morphogenesis based on the vesicle supply center concept. In three dimensions, the vesicle gradient generated by the vesicle supply center is insufficient to explain shape; it is also necessary to know the manner in which the existing surface is displaced during wall expansion.