Deletion of myoE alters hyphal morphology and SynA distribution but not the localization of endocytic patches.

Abstract

<p>Panel A shows a <i>myoE</i>⁺ strain and panel B shows a <i>myoE</i>Δ strain. Both are stained with 10 µg/ml calcofluor. Hyphae in the <i>myoE</i>Δ strain are thicker, vary more in thickness and exhibit more branching near the tip. The amount of chitin staining at the hyphal tip varied from hypha to hypha in wild-type strains as well as <i>myoB</i> and <i>myoE</i> deletion strains. The difference in staining between A and B is not specific to myoEΔ. Panel C shows GFP-SynA in a <i>myoE</i>⁺ strain. SynA is concentrated into the Spitzenkörper at the hyphal tip (arrow) and is also present at the membrane near the tip. Panel D shows GFP-SynA in a <i>myoE</i>Δ strain. SynA is present at the membrane and in puncta in the cytoplasm but is not obviously organized into a Spitzenkörper. Panel E shows the localization of AbpA-mRFP and GFP-SynA in a <i>myoE</i>Δ strain. The image is a single focal plane from a deconvolved Z-series stack. AbpA-containing endocytic patches (arrow) localize to the cortex behind the growing tip and in three dimensions form a collar behind the growing tip. Panel F shows a control <i>myoE</i>⁺ strain (LO1548) also expressing GFP-SynA and AbpA-mRFP. The image is a single focal plane from a deconvolved Z-series stack. The ApbA-containing patches (arrow) appear to be organized into a tighter array and the Spitzenkörper is visible (arrowhead). Note that <i>myoE</i>⁺ hyphae are more consistent in diameter along their length than <i>myoE</i>Δ hyphae (compare A and B) and that the apices in <i>myoE</i>Δ hyphae appear rounder than in <i>myoE</i>⁺ hyphae. A and B are the same magnification as are C and D. Panel G shows branching ahead of the first septum (septum designated with an arrow).</p