The tip growth apparatus of Aspergillus nidulans.
The tip growth apparatus of Aspergillus nidulans.
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DOI：
10.1091/mbc.e07-05-0464
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发表时间：
2008-04
影响因子：
3.3
通讯作者：
Naimeh Taheri-Talesh;T. Horio;L. Araújo‐Bazán;Xiaowei Dou;E. Espeso;M. Peñalva;S. Osmani;B. Oakley
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文献类型：
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作者：
Naimeh Taheri-Talesh;T. Horio;L. Araújo‐Bazán;Xiaowei Dou;E. Espeso;M. Peñalva;S. Osmani;B. Oakley
真菌中的菌丝尖端生长是重要的，因为真菌的经济和医学重要性，并且因为它可能是其他生物中极化生长的有用模型。我们已经调查的核心问题的细胞骨架元素的作用和精确的网站的胞吐和胞吞作用在生长菌丝顶端使用的模式真菌构巢曲霉。荧光融合蛋白的延时成像揭示了一个显着的动态，但高度结构化，尖端生长装置。SYNA（一种突触泡蛋白同源物）和SECC（一种外囊组分）的实时成像显示，囊泡积聚在Spitzenkörper（顶端体）中，并与菌丝顶端的质膜融合。SYNA通过在菌丝顶端后1-2 μ m的内吞斑领处的内吞作用从质膜回收，该内吞斑领随着顶端生长而向前移动。因此，胞吐作用和胞吞作用在空间上是耦合的。抑制剂研究，结合荧光融合蛋白的观察，揭示了肌动蛋白在尖端的胞吐和胞吞以及将尖端生长器保持在一起的功能。微管对于将囊泡递送到尖端区域和将尖端生长装置保持在适当位置是重要的。
Hyphal tip growth in fungi is important because of the economic and medical importance of fungi, and because it may be a useful model for polarized growth in other organisms. We have investigated the central questions of the roles of cytoskeletal elements and of the precise sites of exocytosis and endocytosis at the growing hyphal tip by using the model fungus Aspergillus nidulans. Time-lapse imaging of fluorescent fusion proteins reveals a remarkably dynamic, but highly structured, tip growth apparatus. Live imaging of SYNA, a synaptobrevin homologue, and SECC, an exocyst component, reveals that vesicles accumulate in the Spitzenkörper (apical body) and fuse with the plasma membrane at the extreme apex of the hypha. SYNA is recycled from the plasma membrane by endocytosis at a collar of endocytic patches, 1-2 mum behind the apex of the hypha, that moves forward as the tip grows. Exocytosis and endocytosis are thus spatially coupled. Inhibitor studies, in combination with observations of fluorescent fusion proteins, reveal that actin functions in exocytosis and endocytosis at the tip and in holding the tip growth apparatus together. Microtubules are important for delivering vesicles to the tip area and for holding the tip growth apparatus in position.