show Abstracthide AbstractRegionalized lineage progenitor cells emerged from the onset of gastrulation would facilitate mouse embryonic patterning and build a blueprint for future development. However, the molecular mechanism especially the epigentic mechanism underlying the formation and development of lineage restricted cells has not been fully unveiled. Here,we present a comprehensive landscape of H3K4me3, H3K4me1, H3K9ac, H3K27ac, H3K27me3 and DNA methylation pattern in mouse embryo from pre-streak stage to late-streak stage, and fully analyze the epigenetic mechansim driving the embryonic patterning of mouse gastrula Overall design: To obtain a comprehensive epigenetic landscape of mouse gastrulation and the corresponding lineage development process, we have dissected mouse gastrula from pre-steak stage (E6.5) to late streak stage (E7.5)19 into extra-embryonic (ExE) and embryonic parts, and embryonic parts of E7.0 and E7.5 embryos will be further divided into sub-regions (A, P, AM) due to the emergence of embryo asymmetry.