When glucose-starved cells are replenished with glucose, the key gluconeogenic enzyme, fructose-1,6-bisphosphatase (FBPase), is selectively targeted from the cytosol to the yeast lysosome (vacuole) for degradation. The glucose-induced targeting of FBPase to the vacuole for degradation occurs in cells grown under a variety of metabolic conditions. Immunoelectron microscopic studies demonstrate that the uptake of FBPase by the vacuole is mediated in part by an autophagic process. FBPase can be found on the vacuolar membrane and also at the sites of membrane invaginations. Furthermore, FBPase is associated with different forms of vesicles, which are induced to accumulate inside the vacuole. We have identified peroxisomes as the organelles that are delivered to the vacuole for degradation when cells are replenished with glucose. Ultrastructural studies indicate that peroxisomes are engulfed by the vacuole by an autophagic process, leading to the destruction of whole organelles in the vacuole. Furthermore, the galactose transporter (Gal2p) is also delivered from the plasma membrane to the vacuole for degradation in response to glucose. Gal2p is delivered to the vacuole through the endocytic pathway, as mutants defective in receptor-mediated endocytosis fail to degrade Gal2p in response to glucose.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				J. Pan, X. Pan, N. Wang, M. Ghazizadeh, and A. Yeldandi Characterization of the degradation of recombinant rat urate oxidase in tetracycline controlled gene expression cells J. Electron Microsc. (Tokyo), August 1, 2005; 54(4): 385 - 392. [Abstract] [Full Text] [PDF]

				G.-C. Hung, C. R. Brown, A. B. Wolfe, J. Liu, and H.-L. Chiang Degradation of the Gluconeogenic Enzymes Fructose-1,6-bisphosphatase and Malate Dehydrogenase Is Mediated by Distinct Proteolytic Pathways and Signaling Events J. Biol. Chem., November 19, 2004; 279(47): 49138 - 49150. [Abstract] [Full Text] [PDF]

				C. R. Brown, J. Liu, G.-C. Hung, D. Carter, D. Cui, and H.-L. Chiang The Vid Vesicle to Vacuole Trafficking Event Requires Components of the SNARE Membrane Fusion Machinery J. Biol. Chem., July 3, 2003; 278(28): 25688 - 25699. [Abstract] [Full Text] [PDF]

				F. Reggiori, C.-W. Wang, P. E. Stromhaug, T. Shintani, and D. J. Klionsky Vps51 Is Part of the Yeast Vps Fifty-three Tethering Complex Essential for Retrograde Traffic from the Early Endosome and Cvt Vesicle Completion J. Biol. Chem., February 7, 2003; 278(7): 5009 - 5020. [Abstract] [Full Text] [PDF]

				J. Horak, J. Regelmann, and D. H. Wolf Two Distinct Proteolytic Systems Responsible for Glucose-induced Degradation of Fructose-1,6-bisphosphatase and the Gal2p Transporter in the Yeast Saccharomyces cerevisiae Share the Same Protein Components of the Glucose Signaling Pathway J. Biol. Chem., March 1, 2002; 277(10): 8248 - 8254. [Abstract] [Full Text] [PDF]

				F. Reggiori and D. J. Klionsky Autophagy in the Eukaryotic Cell Eukaryot. Cell, February 1, 2002; 1(1): 11 - 21. [Full Text] [PDF]

				C. R. Brown, J. A. McCann, G. G.-C. Hung, C. P. Elco, and H.-L. Chiang Vid22p, a novel plasma membrane protein, is required for the fructose-1,6-bisphosphatase degradation pathway J. Cell Sci., January 2, 2002; 115(3): 655 - 666. [Abstract] [Full Text] [PDF]

				C. R. Brown, D.-Y. Cui, G. G.-C. Hung, and H.-L. Chiang Cyclophilin A Mediates Vid22p Function in the Import of Fructose-1,6-bisphosphatase into Vid Vesicles J. Biol. Chem., December 14, 2001; 276(51): 48017 - 48026. [Abstract] [Full Text] [PDF]

				J. Horak and D. H. Wolf Glucose-Induced Monoubiquitination of the Saccharomyces cerevisiae Galactose Transporter Is Sufficient To Signal Its Internalization J. Bacteriol., May 15, 2001; 183(10): 3083 - 3088. [Abstract] [Full Text]

				J. Kim, Y. Kamada, P. E. Stromhaug, J. Guan, A. Hefner-Gravink, M. Baba, S. V. Scott, Y. Ohsumi, W. A. Dunn , Jr., and D. J. Klionsky Cvt9/Gsa9 Functions in Sequestering Selective Cytosolic Cargo Destined for the Vacuole J. Cell Biol., April 16, 2001; 153(2): 381 - 396. [Abstract] [Full Text] [PDF]

				C. R. Brown, J. A. McCann, and H.-L. Chiang The Heat Shock Protein Ssa2p Is Required for Import of Fructose-1,6-Bisphosphatase into Vid Vesicles J. Cell Biol., July 11, 2000; 150(1): 65 - 76. [Abstract] [Full Text] [PDF]

				M. Horst, E. C. Knecht, and P. V. Schu Import into and Degradation of Cytosolic Proteins by Isolated Yeast Vacuoles Mol. Biol. Cell, September 1, 1999; 10(9): 2879 - 2889. [Abstract] [Full Text]

				W. Yuan, P. E. Strømhaug, and W. A. Dunn Jr. Glucose-induced Autophagy of Peroxisomes in Pichia pastoris Requires a Unique E1-like Protein Mol. Biol. Cell, May 1, 1999; 10(5): 1353 - 1366. [Abstract] [Full Text]

				M. Hutchins, M Veenhuis, and D. Klionsky Peroxisome degradation in Saccharomyces cerevisiae is dependent on machinery of macroautophagy and the Cvt pathway J. Cell Sci., January 11, 1999; 112(22): 4079 - 4087. [Abstract] [PDF]

				R. S. Gitan, H. Luo, J. Rodgers, M. Broderius, and D. Eide Zinc-induced Inactivation of the Yeast ZRT1 Zinc Transporter Occurs through Endocytosis and Vacuolar Degradation J. Biol. Chem., October 30, 1998; 273(44): 28617 - 28624. [Abstract] [Full Text] [PDF]

				Y. Sakai, A. Koller, L. K. Rangell, G. A. Keller, and S. Subramani Peroxisome Degradation by Microautophagy in Pichia pastoris: Identification of Specific Steps and Morphological Intermediates J. Cell Biol., May 4, 1998; 141(3): 625 - 636. [Abstract] [Full Text] [PDF]

				M.-C. Chiang and H.-L. Chiang Vid24p, a Novel Protein Localized to the Fructose-1,6-bisphosphatase-containing Vesicles, Regulates Targeting of Fructose-1,6-bisphosphatase from the Vesicles to the Vacuole for Degradation J. Cell Biol., March 23, 1998; 140(6): 1347 - 1356. [Abstract] [Full Text] [PDF]

				N. J. Bryant and T. H. Stevens Vacuole Biogenesis in Saccharomyces cerevisiae: Protein Transport Pathways to the Yeast Vacuole Microbiol. Mol. Biol. Rev., March 1, 1998; 62(1): 230 - 247. [Abstract] [Full Text] [PDF]

				H.-L. Shieh and H.-L. Chiang In Vitro Reconstitution of Glucose-induced Targeting of Fructose-1,6-bisphosphatase into the Vacuole in Semi-intact Yeast Cells J. Biol. Chem., February 6, 1998; 273(6): 3381 - 3387. [Abstract] [Full Text] [PDF]

				C. Campbell and P. Thorsness Escape of mitochondrial DNA to the nucleus in yme1 yeast is mediated by vacuolar-dependent turnover of abnormal mitochondrial compartments J. Cell Sci., January 8, 1998; 111(16): 2455 - 2464. [Abstract] [PDF]

				M. Baba, M. Osumi, S. V. Scott, D. J. Klionsky, and Y. Ohsumi Two Distinct Pathways for Targeting Proteins from the Cytoplasm to the Vacuole/Lysosome J. Cell Biol., December 29, 1997; 139(7): 1687 - 1695. [Abstract] [Full Text] [PDF]

				D. A. Pearce and F. Sherman Differential Ubiquitin-dependent Degradation of the Yeast Apo-cytochrome c Isozymes J. Biol. Chem., December 12, 1997; 272(50): 31829 - 31836. [Abstract] [Full Text] [PDF]

				P.-H. Huang and H.-L. Chiang Identification of Novel Vesicles in the Cytosol to Vacuole Protein Degradation Pathway J. Cell Biol., February 24, 1997; 136(4): 803 - 810. [Abstract] [Full Text] [PDF]

				W Yuan, D. Tuttle, Y. Shi, G. Ralph, and W. Dunn Glucose-induced microautophagy in Pichia pastoris requires the alpha-subunit of phosphofructokinase J. Cell Sci., January 8, 1997; 110(16): 1935 - 1945. [Abstract] [PDF]

				H.-L. Shieh, Y. Chen, C. R. Brown, and H.-L. Chiang Biochemical Analysis of Fructose-1,6-bisphosphatase Import into Vacuole Import and Degradation Vesicles Reveals a Role for UBC1 in Vesicle Biogenesis J. Biol. Chem., March 23, 2001; 276(13): 10398 - 10406. [Abstract] [Full Text] [PDF]

				A. Graschopf, J. A. Stadler, M. K. Hoellerer, S. Eder, M. Sieghardt, S. D. Kohlwein, and R. J. Schweyen The Yeast Plasma Membrane Protein Alr1 Controls Mg2+ Homeostasis and Is Subject to Mg2+-dependent Control of Its Synthesis and Degradation J. Biol. Chem., May 4, 2001; 276(19): 16216 - 16222. [Abstract] [Full Text] [PDF]