Dual proteolytic pathways govern glycolysis and immune competence
- Cell. 2014 Dec 18;159(7):1578-90. doi: 10.1016/j.cell.2014.12.001.
- 1. Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; NIAID Clinical Genomics Program, National Institutes of Health, Bethesda, MD 20892, USA.
- 2. Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; NIAID Clinical Genomics Program, National Institutes of Health, Bethesda, MD 20892, USA.
- 3. Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
- 4. Institute of Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
- 5. Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; Great North Children's Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE1 4LP, UK.
- 6. Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK.
- 7. NIHR BRC Translational Immunology Lab, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK.
- 8. Centre for Cardiovascular Sciences, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
- 9. NIAID Clinical Genomics Program, National Institutes of Health, Bethesda, MD 20892, USA; Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
- 10. Department of Pediatrics, Child & Family Research Institute and BC Children's Hospital, University of British Columbia, Vancouver, BC V5Z 4H4, Canada.
- 11. Paediatric Immunology Department, Birmingham Heartlands Hospital, Birmingham B9 5SS, UK.
- 12. Blood and Cancer Center, Starship Children's Hospital, Auckland 1142, New Zealand.
- 13. Great North Children's Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE1 4LP, UK.
- 14. NIHR BRC Translational Immunology Lab, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; MRC Unit Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK.
- 15. Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; Great North Children's Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE1 4LP, UK. Electronic address: [email protected].
- 16. Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; NIAID Clinical Genomics Program, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address: [email protected].
Proteasomes and lysosomes constitute the major cellular systems that catabolize proteins to recycle free Amino acids for energy and new protein synthesis. Tripeptidyl peptidase II (TPPII) is a large cytosolic proteolytic complex that functions in tandem with the proteasome-ubiquitin protein degradation pathway. We found that autosomal recessive TPP2 mutations cause recurrent infections, autoimmunity, and neurodevelopmental delay in humans. We show that a major function of TPPII in mammalian cells is to maintain amino acid levels and that TPPII-deficient cells compensate by increasing lysosome number and proteolytic activity. However, the overabundant lysosomes derange cellular metabolism by consuming the key glycolytic enzyme hexokinase-2 through chaperone-mediated Autophagy. This reduces glycolysis and impairs the production of effector cytokines, including IFN-γ and IL-1β. Thus, TPPII controls the balance between intracellular amino acid availability, lysosome number, and glycolysis, which is vital for adaptive and innate immunity and neurodevelopmental health.