Redox cofactors are essential for the metabolic reactions that support cell proliferation. NADPH is important both to combat oxidative stress and to facilitate reductive reactions in biosynthesis. In this issue, Tran et al. find that the enzyme that produces mitochondrial NADPH is critical in enabling proline synthesis to support cell proliferation when environmental proline is limited.
- Frances F. Diehl
- Matthew G. Vander Heiden
