Septin ring formation and chitin-containing septum formation are aberrant in filaments formed in response to staurosporine. Septin ring formation and chitin-containing septum formation are aberrant in filaments formed in response to staurosporine. (A) Strains were subcultured to log phase in YPD at 30°C, YPD plus 0.5 μg/ml staurosporine at 30°C, or YPD plus 10% serum at 37°C. Shown are representative fluorescence microscopy images of SN95 wild-type cells expressing native levels of GFP-tagged Cdc10 to visualize septin (left panels) and RFP-tagged Hhf1 to visualize DNA (middle panels). The scale bar represents 10 μm. The fluorescence microscopy images were merged with DIC images (right panels). (B) Strains were subcultured to log phase in YPD at 30°C in the presence or absence of 0.5 μg/ml staurosporine. Shown are representative fluorescence microscopy images of SN95 wild-type cells expressing native levels of GFP-tagged Nop1 to visualize nuclei (middle panels) and stained with calcofluor white to visualize chitin (left panels). The scale bar represents 10 μm. The fluorescence microscopy images were merged with DIC images (right panels). Jinglin L. Xie et al. mSphere 2017; doi:10.1128/mSphere.00056-17