Research Topic B - Molecular motors in hyphal growth and pathogenicity of U. maydis
Research articles
Weber, I., Gruber, C, & Steinberg, G. (2003) A class V myosin required for mating, hyphal growth and pathogenicity in the dimorphic plant pathogen Ustilago maydis. Plant Cell, 15, 2826-2842.
Summary - We show here that a class V myosin, Myo5, participates in polarized growth and pathogenicity of U. maydis. Myo5 was indispensable for conjugation tube formation and myo5 mutants were impaired in the perception of pheromones, indicating that this motor is essential for fungal virulence. This is the first report on the role of a molecular motor in a plant pathogen.
Schuchhardt, I., Aßmann, D., Thines, E, Schuberth, C. & Steinberg, G. (2005) Myosin-V, Kinesin-1 and Kinesin-3 cooperate in long-distance transport in hyphal growth of the fungus Ustilago maydis. Mol. Biol. Cell, 16, 5191-5201.
Summary - In this paper we demonstrate that actin- and microtubule-based transport support hyphal growth. Although microtubule plus-ends are directed to the hyphal tip, only kinesin-1 and kinesin-3 are involved in polarized growth, whereas deletion of all other kinesins was without influence on filamentous growth. This is the first systematic study on the role of molecular motor in hyphal growth of fungi.
Weber, I., Aßmann, D., Thines, E., & Steinberg, G. (2006) Polar localizing class V myosin chitin synthases are essential during early plant infection in the plant pathogenic fungus Ustilago maydis. Plant Cell,18, 225-42.
Summary - Here we show that a myosin-chitin synthase, Mcs1, is essential for early plant infection but not in growth ex planta. In contrast, two class IV chitin synthases are required for shaping yeast cells and hyphae outside of the cell. Although the existence of a myosin motor in Mcs1 suggests motor function, motor activity has not yet been demonstrated. This is the first systematic study that analyses all chitin synthases in different developmental stages. It suggests that chitin synthases have development-specific roles, which challenges the dogma that high numbers of chitin synthases indicate redundancy.
Figure 1: Motors in hyphal growth of U. maydis. Note that exo- and endocytosis requires trafficking along the cytoskeleton. The graph was modified from Schuchardt et al. 2005, Mol Biol Cell. 16, 5191.