Maintenance of residential proteins at their respective organelles is essential to ensure function integrity and cellular survival. However, I identified three groups of proteins in budding yeast that show redistribution in a nutrient-dependent manner. Kre2CT-mNeon and mNeon-Rer1p are redistributed from Golgi to ER in cells incubated in nutrient-limited medium. Supplementation of inositol is sufficient for cells to traffic Kre2CT-mNeon back to Golgi but not mNeon-Rer1p. In contrast, supplementation of leucine does the exact opposite. tco89Δ cells showed delayed ER-redistribution of Kre2CT-mNeon which can be partially recovered by wildtype TCO89 allele. The ER staining of Kre2CT-mNeon and mNeon-Rer1p are abolished in ret1-1 mutants under non-permissive temperate. These results su...[ Read more ]

Maintenance of residential proteins at their respective organelles is essential to ensure function integrity and cellular survival. However, I identified three groups of proteins in budding yeast that show redistribution in a nutrient-dependent manner. Kre2CT-mNeon and mNeon-Rer1p are redistributed from Golgi to ER in cells incubated in nutrient-limited medium. Supplementation of inositol is sufficient for cells to traffic Kre2CT-mNeon back to Golgi but not mNeon-Rer1p. In contrast, supplementation of leucine does the exact opposite. tco89Δ cells showed delayed ER-redistribution of Kre2CT-mNeon which can be partially recovered by wildtype TCO89 allele. The ER staining of Kre2CT-mNeon and mNeon-Rer1p are abolished in ret1-1 mutants under non-permissive temperate. These results suggested that Kre2CT-mNeon and mNeon-Rer1p may serve as reporter proteins to study nutrient-dependent protein retrograde trafficking in yeast. In addition, I identified GFP-tagged COPII-subunits that show concentrated punctate structure in cells incubated in YEPD, suggesting that cells may also regulate COPII-mediate anterograde transport to adapt to different nutritional environment.