Cánovas David
Department of Genetics, Faculty of Biology, Universidad de Sevilla, 41012 Sevilla, Spain.
J Fungi (Basel). 2022 Jul 22;8(8):759. doi: 10.3390/jof8080759.
Polarized growth is a defining property of filamentous fungi, which plays an important role in different aspects of their biology, including virulence. However, little information is available about the determinants of cell surface organization and their role in polarized growth. The fungal protein MesA was identified in a genetic screen in and is involved in the stabilization of the polarity axes, but it has no evident role in budding yeast. In this work, I present evidence that in the dimorphic fungal phytopathogen MesA/Mes1 is involved in cell wall stability and polarized growth. mutants were more sensitive to drugs provoking cell wall stress, and they displayed a temperature-sensitive phenotype. Actin cytoskeleton was disorganized in a mutant, suggesting that there is a connection between Mes1, the actin cytoskeleton and polarized morphogenesis. The septin ring was also absent from the bud tip, but not the bud neck. Deletion of provoked defects in endocytosis and vacuolar organization in the cells. Mes1 was essential for strong polarized growth in the hyphal form, but it was dispensable during low or moderate polarized growth in the yeast form in at a permissive temperature. Consistently, mutants showed delayed mating and they were avirulent.
极性生长是丝状真菌的一个决定性特征，在其生物学的不同方面发挥着重要作用，包括毒力。然而，关于细胞表面组织的决定因素及其在极性生长中的作用，目前所知甚少。真菌蛋白MesA于[具体年份]在一次遗传筛选中被鉴定出来，它参与极性轴的稳定，但在芽殖酵母中没有明显作用。在这项研究中，我提供证据表明，在双态真菌植物病原体[具体名称]中，MesA/Mes1参与细胞壁稳定性和极性生长。[具体基因]突变体对引发细胞壁应激的药物更敏感，并且表现出温度敏感型表型。在[具体基因]突变体中，肌动蛋白细胞骨架紊乱，这表明Mes1、肌动蛋白细胞骨架和极性形态发生之间存在联系。芽尖也没有隔膜环，但芽颈处有。[具体基因]的缺失导致细胞内吞作用和液泡组织出现缺陷。Mes1对于菌丝形态的强烈极性生长至关重要，但在允许温度下，在[具体真菌名称]酵母形态的低或中等极性生长过程中它并非必需。一致地，[具体基因]突变体显示交配延迟且无毒力。
