Updated project metadata. Chloroplast biogenesis is indispensable for proper plant development. In a screen for photosynthesis affected mutants, we have identified the pp7l (serine/threonine-protein phosphatase7-like) mutant in which chloroplast development is delayed in cotyledons and young leaves. PP7L constitutes together with PP7 and PP7-long the type 7 subfamily of serine/threonine-specific phosphoprotein phosphatases (PPPs). Here we performed shotgun proteomic experiment in order to profile the changes in protein levels in the pp7l mutants in comparison to the wild-type (Col-0).