Regulation of polarised growth in fungi
Regulation of polarised growth in fungi
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DOI：
10.1016/j.fbr.2008.07.001
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发表时间：
2008-05-01
影响因子：
6
通讯作者：
Sudbery, Peter E.
中科院分区：
文献类型：
--
作者：
Sudbery, Peter E.
真菌的极化生长是通过将分泌囊泡沿着由细胞骨架元件形成的轨道输送到细胞表面上的特定位点而发生的，在细胞表面上，分泌囊泡在与质膜融合之前与称为外囊的多蛋白结构对接。芽殖酵母，酿酒酵母（Saccharomyces cerevisiae）提供了一个有用的模型来研究所涉及的机制及其控制。皮层标记，提供芽位点选择途径在出芽，隔蛋白环在胞质分裂或刺激的信息素反应受体在交配过程中，通过上游信号传导途径，以本地化Cdc24 p，GEF的rho家族GTdR，Cdc42 p。在其GTP结合形式中，Cdc 42 p激活称为极化体的多蛋白复合物，极化体使肌动蛋白缆沿着成核，分泌囊泡沿所述肌动蛋白缆运输到细胞表面。菌丝可以以比酵母芽的延伸快几个数量级的速率伸长，因此理解菌丝生长将需要对酵母范例进行实质性修改。菌丝的快速生长是由一种叫做Spitzenkorper的结构驱动的，它位于生长尖端的后面，富含分泌囊泡。据认为，分泌囊泡被递送到顶端区域，在那里它们积聚在Spitzenkorper中。Spitzenkorper然后作为囊泡供应中心，它已被假定，囊泡退出Spitzenkorper在所有方向，但由于其接近，尖端接收更大的浓度囊泡每单位面积比subapical区域。没有明显的等价物芽位选择途径，以提供一个空间地标的极化生长菌丝。然而，一个新兴的模式是分裂酵母，裂殖酵母，极化生长的网站，是通过传递kelch重复蛋白，Teal，沿着微管的方式标记。Spitzenkorper与极化体的关系以及促进其形成的机制是当前研究的重点。(C)2008年英国真菌学会。由爱思唯尔有限公司出版。保留所有权利。
Polarised growth in fungi occurs through the delivery of secretory vesicles along tracks formed by cytoskeletal elements to specific sites on the cell surface where they dock with a multiprotein structure called the exocyst before fusing with the plasma membrane. The budding yeast, Saccharomyces cerevisiae has provided a useful model to investigate the mechanisms involved and their control. Cortical markers, provided by bud site selection pathways during budding, the septin ring during cytokinesis or the stimulation of the pheromone response receptors during mating, act through upstream signalling pathways to localise Cdc24p, the GEF for the rho family GTPase, Cdc42p. In its GTP-bound form, Cdc42p activates a multiprotein complex called the polarisome which nucleates actin cables along which the secretory vesicles are transported to the cell surface. Hyphae can elongate at a rate orders of magnitude faster than the extension of a yeast bud, so understanding hyphal growth will require substantial modification of the yeast paradigm. The rapid rate of hyphal growth is driven by a structure called the Spitzenkorper, located just behind the growing tip and which is rich in secretory vesicles. It is thought that secretory vesicles are delivered to the apical region where they accumulate in the Spitzenkorper. The Spitzenkorper then acts as vesicle supply centre, and it has been postulated that vesicles exit the Spitzenkorper in all directions, but because of its proximity, the tip receives a greater concentration of vesicles per unit area than subapical regions. There are no obvious equivalents to the bud site selection pathway to provide a spatial landmark for polarised growth in hyphae. However, an emerging model is the way that the site of polarised growth in the fission yeast, Schizosaccharomyces pombe, is marked by delivery of the kelch repeat protein, Teal, along microtubules. The relationship of the Spitzenkorper to the polarisome and the mechanisms that promote its formation are key questions that form the focus of current research. (C) 2008 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.