summary
Chaperone-mediated autophagy (CMA) is the only type of autophagy in mammalian cells able to selectively degrade cytosolic proteins in lysosomes. CMA is maximally activated in response to stressors such as prolonged starvation, exposure to toxic compounds, or oxidative stress. We have found that CMA activity decreases in aging and in some age-related disorders such as Parkinson’s disease. Impaired CMA under these conditions may be responsible for the accumulation of damaged proteins inside cells and for their higher vulnerability to stressors. In contrast to other forms of autophagy, where substrates are engulfed or sequestered along with other cytosolic components, CMA substrates are translocated one-by-one across the lysosomal membrane. Changes in the levels/activity of the lysosomal components required for substrate translocation can be used to stimulate CMA activity. However, the most unequivocal method to measure CMA is by directly tracking the translocation of substrate proteins into isolated lysosomes.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Massey, A., Zhang, C. and Cuervo, A. (2006) Chaperone-mediated autophagy in aging and disease. Curr. Top. Dev. Biol. 73, 205–235.
Dice, J. (1990) Peptide sequences that target cytosolic proteins for lysosomal proteolysis. Trends Biochem. Sci. 15, 305–309.
Chiang, H., Terlecky, S., Plant, C. and Dice, J. (1989) A role for a 70 kDa heat shock protein in lysosomal degradation of intracellular protein. Science 246, 382–385.
Majeski, A. and Dice, J. (2004) Mechanisms of chaperone-mediated autophagy. Int. J. Biochem. Cell Biol. 36, 2435–2444.
Cuervo, A. and Dice, J. (1996) A receptor for the selective uptake and degradation of proteins by lysosomes. Science 273, 501–503.
Salvador, N., Aguado, C., Horst, M. and Knecht, E. (2000) Import of a cytosolic protein into lysosomes by chaperone-mediated autophagy depends on its folding state. J. Biol. Chem. 275, 27447–27456.
Agarraberes, F., Terlecky, S. and Dice, J. (1997) An intralysosomal hsp70 is required for a selective pathway of lysosomal protein degradation. J. Cell. Biol. 137, 825–834.
Terlecky, S. and Dice, J. (1993) Polypeptide import and degradation by isolated lysosomes. J. Biol. Chem. 268, 23490–23495.
Aniento, F., Papavassiliou, A. G., Knecht, E. and Roche, E. (1996) Selective uptake and degradation of c-fos and v-fos by rat liver lysosomes. FEBS Lett. 390, 47–49.
Wing, S., Chiang, H. L., Goldberg, A. L. and Dice, J. F. (1991) Proteins containing peptide sequences related to KFERQ are selectively depleted in liver and heart, but not skeletal muscle, of fasted rats. Biochem. J. 275, 165–169.
Cuervo, A., Knecht, E., Terlecky, S. and Dice, J. (1995) Activation of a selective pathway of lysosomal proteolysis in rat liver by prolonged starvation. Am. J. Physiol. 269, C1200–C1208.
Kiffin, R., Christian, C., Knecht, E. and Cuervo, A. (2004) Activation of chaperone-mediated autophagy during oxidative stress. Mol. Biol. Cell. 15, 4829–4840.
Cuervo, A., Hildebrand, H., Bomhard, E. and Dice, J. (1999) Direct lysosomal uptake of alpha2-microglobulin contributes to chemically induced nephropathy. Kidney Int. 55, 529–545.
Cuervo, A. M., Stefanis, L., Fredenburg, R., Lansbury, P. T. and Sulzer, D. (2004) Impaired degradation of mutant alpha-synuclein by chaperone-mediated autophagy. Science 305, 1292–1295.
Cuervo, A. M. and Dice, J. F. (2000) Age-related decline in chaperone-mediated autophagy. J. Biol. Chem. 275, 31505–31513.
Cuervo, A. M., Dice, J. F. and Knecht, E. (1997) A population of rat liver lysosomes responsible for the selective uptake and degradation of cytosolic proteins. J. Biol. Chem. 272, 5606–5615.
Cuervo, A., Terlecky, S., Dice, J. and Knecht, E. (1994) Selective binding and uptake of ribonuclease A and glyceraldehyde-3-phosphate dehydrogenase by isolated rat liver lysosomes. J. Biol. Chem. 269, 26374–26380.
Aniento, F., Roche, E., Cuervo, A. M. and Knecht, E. (1993) Uptake and degradation of glyceraldehyde-3-phosphate dehydrogenase by rat liver lysosomes. J. Biol. Chem. 268, 10463–10470.
Dworniczak, B. and Mirault, M. (1987) Structure and expression of a human gene coding for a 71 kd heat shock ‘cognate’ protein. Nucl. Acids Res. 15, 5181–5197.
Auteri, J., Okada, A., Bochaki, V. and Dice, J. (1983) Regulation of intracellular protein degradation in IMR- 90 human diploid fibroblasts. J. Cell Physiol. 115, 159–166.
Finn, P. F. and Dice, J. F. (2005) Ketone bodies stimulate chaperone-mediated autophagy. J. Biol. Chem. 280, 25864–25870.
Fuertes, G., Martin De Llano, J.,Villarroya, A., Rivett, A. and Knecht, E. (2003) Changes in the proteolytic activities of proteasomes and lysosomes in human fibroblasts produced by serum withdrawal, amino-acid deprivation and confluent conditions. Biochem. J. 375, 75–86.
Massey, A. C., Kaushik, S., Sovak, G., Kiffin, R. and Cuervo, A. M. (2006) Consequences of the selective blockage of chaperone-mediated autophagy. Proc. Natl. Acad. Sci. USA 103, 5905–5910.
Cuervo, A. and Dice, J. (2000) Unique properties of lamp2a compared to other lamp2 isoforms. J. Cell Sci. 113, 4441–4450.
Cuervo, A. and Dice, J. (2000) Regulation of lamp2a levels in the lysosomal membrane. Traffic 1, 570–583.
Lowry, O., Rosebrough, N., Farr, A. and Randall, R. (1951) Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193, 265–275.
Laemmli, U. (1970) Cleavage of structural proteins during the assembly of the head of the bacteriophage T4. Nature 227, 680–685.
Storrie, B. and Madden, E. (1990) Isolation of subcellular organelles. Methods Enzymol. 182, 203–225.
Acknowledgments
We would like to gratefully acknowledge the members of our laboratory for their valuable suggestions. Research in our laboratory is supported by National Institutes of Health/National Institute of Aging grants AG021904 and AG19834 and an Ellison Medical Foundation Award.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2008 Humana Press, a part of Springer Science+Business Media, LLC
About this protocol
Cite this protocol
Kaushik, S., Cuervo, A.M. (2008). Chaperone-Mediated Autophagy. In: Deretic, V. (eds) Autophagosome and Phagosome. Methods in Molecular Biology™, vol 445. Humana Press. https://doi.org/10.1007/978-1-59745-157-4_15
Download citation
DOI: https://doi.org/10.1007/978-1-59745-157-4_15
Publisher Name: Humana Press
Print ISBN: 978-1-58829-853-9
Online ISBN: 978-1-59745-157-4
eBook Packages: Springer Protocols