Fig. 5. Degradation of Byr4p requires Cdc16p. (A) Protein extracts were prepared from the indicated strains grown exponentially at 25°C or shifted to 36°C for 4 hours before harvesting. Extracts were analysed on a western blot probed with the indicated antibodies. Two lanes to the right of the spg1 sample have been deleted from the image of the gel as they show the effects of a mutant not discussed in this study. (B) Protein extracts were prepared from cdc16::u4+ mob1-R4, in which expression of the indicated fragment of byr4 from the nmt1 promoter had been induced for 20 hours at 25°C in EMM2 medium. Extracts were analysed on a western blot probed with the indicated antibodies. (C) Protein extracts were prepared from leu1::spg1-B8-GFP spg1::u4+ cells in which expression of the indicated fragment of byr4 from the nmt1 promoter had been induced for 16 hours at 25°C in EMM2 medium before shifting to 36°C for 5 hours. Extracts were analysed on a western blot probed with the indicated antibodies.