Fig. 1.

Ezh2 is required in mesoderm for lung development. (A) Ezh2^mesoderm-KO mutant mice are cyanotic shortly after birth. (B) Lungs from Ezh2^mesoderm-KO mice at P0 are not buoyant in PBS (n=3), whereas control lungs float (n=4). (C,D) Ventral (C) and dorsal (D) views of Ezh2^mesoderm-KO show reduced lung size at E18.5. (E) IHC for BrdU at E18.5 reveals decreased BrdU incorporation in the GFP⁺ mesoderm of mutants. (F) BrdU incorporation quantified by litter, showing an average 50% reduction in Ezh2^mesoderm-KO mutants relative to their siblings (P=0.0018). (G) IHC for Cdkn2a (green) reveals increased expression in mutants at E18.5; the red channel distinguishes autofluorescent blood cells (BC) from specific signal. (H) qPCR for Cdkn2a expression shows ectopic expression in the mutants at E14.5 and E18.5, whereas signal was not detected in controls. (I) ChIP-qPCR for H3K27me3 in isolated lung mesoderm at E18.5 (n=4). The Cdkn2a promoter is enriched relative to non-repressed control loci. Error bars indicate s.e.m. Scale bars: 50 µm.