FIGURE 6.
Gdh3 protein is stable throughout all growth stages, whereas Gdh1 is subjected to stationary phase-specific degradation. A, immunoblot analysis of the Gdh1 and Gdh3 proteins in yeast cells at different growth stages. Yeast strains (WT, Δgdh1, Δgdh3, Δgdh1Δgdh3/YCp111, Δgdh1Δgdh3/Gdh1, Δgdh1Δgdh3/YCpGdh3) were grown in SCD, and samples were taken after 24 and 48 h of culture. Cell extracts were immunoblotted and probed with anti-Gdh1, anti-Gdh3 and anti-tubulin antibodies. B, immunoblot analysis of the FLAG-tagged Gdh1 and Gdh3 proteins in yeast cells carrying the promoter-swapped derivatives of GDH1 and GDH3 at different growth stages. Yeast strains (Δgdh1Δgdh3/YCpGdh1-FLAG, Δgdh1Δgdh3/YCpGdh3-FLAG, Δgdh1Δgdh3/YCpPGDH1-Gdh3-FLAG, and Δgdh1Δgdh3/YCpPGDH3-Gdh1-FLAG) were grown in SCD and samples were taken after 12, 24, 48, and 72 h of culture. Cell extracts were immunoblotted and probed with anti-FLAG and anti-tubulin antibodies.