Abstract:
In filamentous fungi, microtubules are important for polar growth and morphological maintenance and serve as rails for intracellular trafficking. The molecular mechanisms associated with microtubules have been analyzed. However, little is known about when and where tubulin, a component of microtubules, is biosynthesized in multinuclear and multicellular filamentous fungi. In this study, we visualized microtubules based on the enhanced green fluorescence protein (EGFP)-labeled α-tubulin and β-tubulin mRNA tagged by the EGFP-mediated MS2 system in living yellow Koji mold Aspergillus oryzae cells in order to understand the spatiotemporal production mechanism of tubulin. We found that mRNA of btuA, encoding for β-tubulin, localized at dot-like structures through the apical, middle and basal regions of the hyphal cells. In addition, some btuA mRNA dots showed microtubule-dependent motor protein-like dynamics in the cells. Furthermore, it was found that btuA mRNA dots were decreased in the cytoplasm just before mitosis but increased immediately after mitosis, followed by a gradual decrease. In summary, the localization and abundance of β-tubulin mRNA is spatiotemporally regulated in living A. oryzae hyphal cells.
摘要:
在丝状真菌中,微管对于极性生长和形态维持很重要,并且可以作为细胞内运输的轨道。已经分析了与微管相关的分子机制。然而,人们对微管蛋白何时何地知之甚少,微管的一个组成部分,在多核和多细胞丝状真菌中生物合成。在这项研究中,我们基于增强型绿色荧光蛋白(EGFP)标记的α-微管蛋白和β-微管蛋白mRNA在活黄曲霉菌米曲霉细胞中被EGFP介导的MS2系统标记,以了解微管蛋白的时空产生机制。我们发现btuA的mRNA,编码β-微管蛋白,通过顶端定位在点状结构上,菌丝细胞的中部和基底区域。此外,一些btuAmRNA点在细胞中显示微管依赖性运动蛋白样动力学。此外,发现有丝分裂前btuAmRNA点在细胞质中减少,但有丝分裂后立即增加,随后逐渐减少。总之,β-微管蛋白mRNA的定位和丰度在活的米曲霉菌丝细胞中受到时空调控。