Mapping the Chromatin State Dynamics in Myoblasts. Mus musculus

The chromatin state in developing body parts provides a zip code to cellular populations that direct their cell fates. We used antibodies for H3K4me3, H3K27me3 and Pol2, to identify the chromatin state signature of the Pitx2-null mouse forelimb during mid-gestation, at embryonic day 12. The families of genes marked included those related to transcription, transcriptional regulation, and embryonic organ development. Transcription factors specific for muscle development were characterized by bivalent chromatin, as E12 is a transition time point from embryonic to fetal myogenesis. The identified chromatin state of muscle specific genes was in strong correlation with their observed expression profile. Overall design: Examination of the histone marks H3K4me3, H3k27me3, and Pol2 in whole E12.5 forelimb tissues from Pitx2 null mice using the Illumina HiSeq 2000