Figure 9.

The mesA1 mutation alters the distribution of sterol-rich membrane domains. Wild-type (GR5) and mesA1 (ACP21) hyphae were grown in YGV at 28°C for 14 h. They were subsequently stained with filipin (25 μg/ml) for 5 min. (A and B) Sterol-rich membrane domains localize to a ring structure at septation sites (A) and to a patch at the tips (B) of wild-type hyphae. (C–F) Sterol-rich membrane domains fail to form a discrete patch at the tips of mesA1 hyphae. Instead, they appear randomly distributed around the surface of hyphal tips cells, with occasional bright spots (arrows) observed at both apical and subapical sites. Localization to septation sites is not affected. Bars, 5 μm.