Hematopoietic stem cells (HSCs) are at the helm of the hierarchically organized hematopoietic system that ensures the lifelong production of all blood cells. HSCs depend on metabolic cues to secure their protective quiescent status and to enable rapid activation and replenishment of the blood system in response to stressful situations such as infections, excessive bleeding, or chemotherapy-induced myeloablation (1–3). On pages 1156 and 1152 of this issue, Ito et al. (4) and Taya et al. (5), respectively, uncover important roles for the degradation of defective mitochondria (mitophagy) and the amino acid valine in HSC maintenance and function.
Authors: Pia Sommerkamp, Andreas Trumpp