Highlights d Deviation from normal cell size interferes with cell function and proliferation d DNA becomes limiting for cell function if cells grow too large d Uncoupling of protein synthesis and volume causes cytoplasm dilution in big cells d Excessive cell growth contributes to functional decline in senescence

A study of acute lung injury reveals the involvement of transcription factor HIF1A in lung protection, where normoxic HIF1A stabilization functions to control alveolar epithelial glucose metabolism.