Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México.
FEMS Yeast Res. 2012 Aug;12(5):547-56. doi: 10.1111/j.1567-1364.2012.00805.x. Epub 2012 Apr 23.
One of the most important physicochemical factors that affect cell growth and development is pH, and living organisms have developed specific mechanisms to adapt to media with variable pH values. Most fungi posses a specific mechanism for such adaptation: the Pal/Rim pathway. To analyze the different metabolic processes regulated by this pathway, and its possible relationships with other physiological regulatory mechanisms, we analyzed the phenotype of a mutant in the PALB/RIM13 gene of the phytopathogenic fungus Ustilago maydis. The mutant displayed important alterations in the synthesis and organization of the cell wall and was affected in its response to stress, revealing its relationship with the MAPKC pathway involved in maintaining the integrity of the cell wall, and the stress response pathway, but not with the HOG pathway. An important observation was that the mutant, in contrast to the wild-type strain, was unable to maintain a constant intracellular pH, suggesting that probably the main function of the Pal/Rim pathway, in collaboration with other regulatory mechanisms, is to maintain a constant intracellular pH, despite the changes occurring in the environment.
影响细胞生长和发育的最重要的理化因素之一是 pH 值，生物体已经发展出特定的机制来适应 pH 值变化的介质。大多数真菌都具有这种适应的特定机制：Pal/Rim 途径。为了分析该途径调节的不同代谢过程及其与其他生理调节机制的可能关系，我们分析了植物病原菌玉米黑粉菌 PALB/RIM13 基因突变体的表型。该突变体在细胞壁的合成和组织方面表现出重要的改变，并且对胁迫的反应受到影响，这揭示了它与 MAPKC 途径（涉及维持细胞壁完整性和应激反应途径）的关系，但与 HOG 途径无关。一个重要的观察结果是，突变体与野生型菌株相比，无法维持恒定的细胞内 pH 值，这表明 Pal/Rim 途径的主要功能（与其他调节机制一起）可能是在环境发生变化时，维持恒定的细胞内 pH 值。
