Endothelial and hematopoietic-“specific” gene expression profiles of fractioned 9.5-dpc yolk sac and BM cells. RT-PCR analysis revealed the gene expression profile of cells sorted from 9.5-dpc yolk sac and adult BM. The 9.5-dpc Tie2-GFP⁺ and Tie2-GFP+Flk1+CD41+ yolk sac cells express both endothelial and hematopoietic-“specific” gene transcripts. The Tie2-GFP⁺Flk1+CD41-yolk sac cells express endothelial-“specific” gene products, whereas BM Sca-1⁺ckit+lin-cells express hematopoietic-“specific” genes only. These data are representative of 3 independent analyses.