The transcriptome analysis of controls and Mesp1 null embryos at gastrulation stage in mice

MESP1 and MESP2 are transcriptional factors involved in mesoderm specification, somite boundary formation, and somite polarity regulation. We established Mesp1 KO mice using genome editing techniques without introducing selection markers commonly used before. The Mesp1 KO did not display any phenotype, including heart formation defects, which were reported previously. We noted up-regulation of Mesp2 in the Mesp1 KO embryos. We further conducted the transcriptome analysis using controls and Mesp1 KO embryos at early bud and late bud stage embryos, and found only a few genes including Mesp2 were up-regulated in the Mesp1 KO embryos. These data suggested that it is likely that MESP2 rescues the loss of MESP1 in mesoderm specification.