Figure 1.

Mep2 forms a multimeric complex and is membrane localized in cells undergoing pseudohyphal growth. (A) Membrane fractions from haploid mep2Δ cells containing a plasmid expressing Mep-N4Q-FLAG or a control vector that had been grown in low-ammonium medium (SLAD) were resolved under native conditions, and the FLAG epitope was detected by Western analysis. (B) Mep2-FLAG was immunoprecipitated from control cells and cells expressing an Mep2-GFP fusion protein that had been grown in SLAD medium. Diploid MLY108a/α cells (mep2Δ/mep2Δ) expressing Mep2-GFP were grown on low-ammonium medium (SLAD) plates for 6 d. The Mep2 fusion protein was localized by direct epifluorescence microscopy in cells at the center of the colony (C), within cells that had formed pseudohyphae (D), and at the edge of the colony (E).