The sedoheptulose kinase CARKL directs macrophage polarization through control of glucose metabolism

Cell Metab. 2012 Jun 6;15(6):813-26. doi: 10.1016/j.cmet.2012.04.023.

Abstract

Immune cells are somewhat unique in that activation responses can alter quantitative phenotypes upwards of 100,000-fold. To date little is known about the metabolic adaptations necessary to mount such dramatic phenotypic shifts. Screening for novel regulators of macrophage activation, we found nonprotein kinases of glucose metabolism among the most enriched classes of candidate immune modulators. We find that one of these, the carbohydrate kinase-like protein CARKL, is rapidly downregulated in vitro and in vivo upon LPS stimulation in both mice and humans. Interestingly, CARKL catalyzes an orphan reaction in the pentose phosphate pathway, refocusing cellular metabolism to a high-redox state upon physiological or artificial downregulation. We find that CARKL-dependent metabolic reprogramming is required for proper M1- and M2-like macrophage polarization and uncover a rate-limiting requirement for appropriate glucose flux in macrophage polarization.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Carbohydrate Metabolism
  • Cell Line
  • Cell Polarity*
  • Double-Blind Method
  • Down-Regulation
  • Endotoxemia / enzymology
  • Endotoxemia / immunology
  • Energy Metabolism
  • Gene Expression Regulation, Enzymologic
  • Glucose / metabolism*
  • Humans
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Lipopolysaccharides / pharmacology
  • Macrophages / enzymology*
  • Macrophages / immunology
  • Macrophages / metabolism
  • Macrophages / physiology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Models, Molecular
  • Phenotype
  • Phosphotransferases (Alcohol Group Acceptor) / chemistry
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Protein Structure, Tertiary
  • Receptors, Immunologic / genetics
  • Receptors, Immunologic / metabolism
  • Transcription Factors / chemistry
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Interleukin-6
  • Lipopolysaccharides
  • Receptors, Immunologic
  • Transcription Factors
  • Tumor Necrosis Factor-alpha
  • Phosphotransferases (Alcohol Group Acceptor)
  • SHPK protein, human
  • Glucose