Aspergillus nidulans swo Mutants Show Defects in Polarity Establishment, Polarity Maintenance and Hyphal Morphogenesis

Aspergillus nidulans swo mutants show defects in polarity establishment, polarity maintenance and hyphal morphogenesis.

When the spores of filamentous fungi break dormancy, they grow isotropically, adding cell wall material uniformly in every direction. Later they switch to polarized growth, with new material added to the tip of an emerging germ tube. To identify genes involved in the synthesis and localization of cell wall material in filamentous fungi, we screened a collection of temperature-sensitive Aspergil...

Hyphal morphogenesis in Aspergillus nidulans

The formation of hyphae that grow solely by apical extension is a defining feature of filamentous fungi. Hyphal morphogenesis involves several key steps, including the establishment and maintenance of a stable polarity axis, as well as cell division via the deposition of septa. Several filamentous fungi have been employed in attempts to decipher the mechanisms underlying these steps. Amongst th...

Endocytic machinery protein SlaB is dispensable for polarity establishment but necessary for polarity maintenance in hyphal tip cells of Aspergillus nidulans.

The Aspergillus nidulans endocytic internalization protein SlaB is essential, in agreement with the key role in apical extension attributed to endocytosis. We constructed, by gene replacement, a nitrate-inducible, ammonium-repressible slaB1 allele for conditional SlaB expression. Video microscopy showed that repressed slaB1 cells are able to establish but unable to maintain a stable polarity ax...

Ras GTPase-activating protein regulation of actin cytoskeleton and hyphal polarity in Aspergillus nidulans.

Aspergillus nidulans gapA1, a mutation leading to compact, fluffy colonies and delayed polarity establishment, maps to a gene encoding a Ras GTPase-activating protein. Domain organization and phylogenetic analyses strongly indicate that GapA regulates one or more "true" Ras proteins. A gapADelta strain is viable. gapA colonies are more compact than gapA1 colonies and show reduced conidiation. g...

Aspergillus nidulans in of Actin Cytoskeleton and Hyphal Polarity Ras GTPase-Activating Protein Regulation