Fig. 3.

Sterol supplementation partially suppresses erg4Δ shmooing and cell fusion defects. (A) erg4Δ cells were grown in anaerobic conditions in the presence of ergosterol and cholesterol. Cells were then harvested and treated with α-factor for 3 h, fixed, and observed under the microscope for shmoo formation quantification. Error bars indicate SEs. (B–D) Cell fusion assay carried out with erg4Δ cells grown anaerobically either in the presence or absence of ergosterol and then mated with wild-type MATα cells bearing cytoplasmic GFP. Total cell fusion scores are shown in B. Different classes of mating pairs were classified depending on either the presence (Class I) or absence (Class II) of proper shmoo morphology in the erg4Δ partner, as shown in C. A breakdown of cell fusion scores for each class of mating pair, genotype, and growing conditions is shown in D. Error bars indicate standard errors.