FIG 3.
Effect of endocytosis-impairing mutations on the localization of PalH-GFP. (A) Wild-type strain carrying a single-copy integration of a transgene driving the expression of PalH-GFP under the control of the moderately strong gpdAmini promoter (30). The boxed inset is shown at double magnification to better illustrate the faint GFP staining of the plasma membrane. Internal structures are endosomes and vacuoles. (B) sagAΔ strain expressing PalH-GFP; note the faint yet consistently greater staining of the plasma membrane compared to that of the wild-type control. (C) arfBΔ strain expressing PalH-GFP. Note the heterogeneous population consisting of cells with strong and moderate labeling of the plasma membrane, in both cases uniformly. The boxed hypha shows a cell of the moderate labeling and “more hyphal” class. (D) fimAΔ strain expressing PalH-GFP. Note the heterogeneous population, as in the case of the arfBΔ mutant. Fields in panels C and D are shown at half the magnification of those in panels A and B to illustrate population heterogeneity. As the gpdAmini::palH-gfp transgene was, in all cases, a single-copy integration of the construct targeted to the pyroA locus, levels of PalH-GFP expression are equivalent in all cases.