Fig. 3. Electron micrographs of the sso1-1 sso2 strain H1239 at permissive and restrictive temperatures. The cells were grown in YPD at 24°C to an A₆₀₀ of 0.3. The cell culture was then split into subcultures grown either at 24°C or 38°C. The cells were fixed after 3 hours of growth and samples were processed for electron microscopy. (a) The sso1-1 sso2 cells accumulate transport vesicles at 38°C. (b) They also have problems with completing cytokinesis and frequently accumulate vesicles at the septum. (c) Cells grown at 24°C do not accumulate vesicles or display incomplete septum formation, but occasionally have wider bud necks than wild-type cells. Bars, 500 nm (a); 200 nm (b); 1 µm (c).