GSE184548
Mitochondrial pyruvate metabolism and glutaminolysis toggle steady-state and emergency myelopoiesis
RNA-sequencing was performed to look for transcriptional differences between wild-type and Mpc2-deficient granulocyte-macrophage progenitors. Very few genes were dysregulated in knockout cells relative to wild-type. Gls Mpc2 double knockouts were additionally analyzed to examine extent of Gls and Mpc2 deletion relative to single knockouts. Paper abstract: Hematopoietic homeostasis is maintained by stem and progenitor cells in part by extrinsic feedback cues triggered by mature cell loss. We demonstrate a different mechanism by which hematopoietic progenitors intrinsically anticipate and prevent the loss of mature progeny through metabolic switches. We examined hematopoiesis in mice conditionally deficient in long-chain fatty acid oxidation (carnitine palmitoyltransferase 2, Cpt2), glutaminolysis (glutaminase, Gls), or mitochondrial pyruvate import (mitochondrial pyruvate carrier 2, Mpc2). While genetic ablation of Cpt2 or Gls minimally impacted most blood lineages, deletion of Mpc2 led to a sharp decline in mature myeloid cells. However, MPC2-deficient myeloid cells rapidly recovered due to a transient increase in myeloid progenitor proliferation. Competitive bone marrow chimera and stable isotope tracing experiments demonstrated that this proliferative burst was intrinsic to MPC2-deficient progenitors and accompanied by a metabolic switch to glutaminolysis. Thus, hematopoietic progenitors intrinsically adjust to metabolic perturbations independently of feedback from downstream mature cells to maintain homeostasis. Overall design: RNA-sequencing of wild-type, Mpc2 knockout, Gls knockout, and Gls Mpc2 double knockout granulocyte-macrophage progenitors