Purine Salvaging in Hematopoietic Stem Cells

Given that metabolism controls stem cell function and that purine metabolism represents a critical component of cellular metabolism, researchers from the laboratory of Hartmut Geiger (Universität Ulm, Germany) set out to discover a potential link. In their new STEM CELLS study, Vogel et al. report that the reduced activity of the purine salvaging enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) in hematopoietic stem cells results in reduced fitness, an altered cell cycle profile, and the modulation of mitochondrial function. Overall, the authors suggest that the phenotype of HPRT low hematopoietic stem cells derives from elevated levels of purine degradation rather than a lack of purine recycling, implying a significant role for HPRT-mediated purine salvaging for hematopoietic stem cells function.