Fig. 8. The effect of deletion of SLA1 on receptor-mediated endocytosis. (A,B) KAY316 (SLA1) and KAY391 (sla1) cells were grown to log phase. -factor (2.5 µg/ml) was added and samples taken and processed for immunofluorescence microscopy at the times indicated. (C) Cells were assessed at each time point for whether the Ste2p-myc staining was at the cortex of cells (n200 for each time point).

(D) Uptake of radiolabelled pheromone was monitored in KAY316 and KAY391 strains to further quantify the internalisation defect of sla1 cells. The graph plotted is the ratio of radioactivity associated with the cells at each time point relative to the initial time zero level of labelling.