FIGURE 1.

Characterization of fission yeast strains expressing human profilin-I. Wild-type fission yeast cells transformed with either an empty pREP3X plasmid or a pREP3X plasmid containing wild-type or mutant Hs profilin-I cDNAs were grown in medium without thiamine to induce expression of Hs profilin-I. A, differential interference contrast and fluorescence micrographs of control cells and cells expressing wild-type Hs profilin-I or Hs profilin-I mutants Y6D R88E. Cells were grown at 25 °C for 26 or 36 h in minimal (Earle's minimal medium) liquid media before staining with Hoechst dye to show nuclei and B, distribution of phenotypes over time of expression of profilin-I variants. Symbols: open squares, cells with normal septa; open triangles, cells with abnormal septa; open circles, cells with multiple septa; filled circles, lysed cells.