Both Lmo2+ and Gata1+ hematopoietic cells are restricted by BMP signaling. Representative embryos are shown that are either control (A,C,E,G) or derived from fertilized eggs injected with either I(lmo2:δBR)I (B,D) or I(gata1:δBR)I (F,H), and analyzed for gene expression by in situ hybridization. The markers tested are as indicted: (A,B) scl; (C,D) lmo2; (E,F) gata1; (G,H) flk1. Expression of both scl and lmo2 is enhanced by expression of the mutant receptor in Lmo2+ cells (arrowheads in B and D), while gata1 (the hematopoietic marker; arrowheads) but not flk1 (the endothelial marker; arrows) is enhanced when the receptor is expressed in Gata1+ cells (E-H). Views are flat-mounted dorsal, anterior towards the left (A-F) or lateral, anterior towards the left (G,H).
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