Figure 1. Key findings of this study (IMAGE) Tokyo Medical and Dental University Caption Key findings of this study：Rasip1 is involved in the formation of hematopoietic stem cell-containing hematopoietic cell clusters in midgestation mouse embryo. Hematopoietic stem cells first arise in Sox17-expressing cells in hematopoietic cell clusters formed in the dorsal aorta at midgestation. Sox17 directly interacts with the Rasip1 gene promoter and induces the Rasip1 gene expression. Overexpression of Rasip1 in hematopoietic cluster forming cells led to maintenance of the clusters with high hematopoietic activity, while knockdown of Rasip1 in Sox17-transduced cells impeded the cluster formation and diminished the hematopoietic ability. Credit Department of Stem Cell Regulation, TMDU Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.