Fig. 4 Positive and negative cis-acting elements regulating hematopoietic expression of GATA-1. Transgenic zebrafish expressing green fluorescent protein from the GATA-1 promoter were generated by microinjection of GATA-1?GFP constructs and selection of transgenic founder lines. 18-somite-stage progeny are shown. In (A), the transgene contains the full-length GATA-1 promoter . GFP expression is confined to hematopoietic progenitors. In (B), deletion of a negative cis-acting element leads to ectopic GFP expression in notochord (arrow); hematopoietic expression is not affected. (Courtesy of Dr. Shuo Lin.)
Reprinted from Developmental Biology, 216(1), Amatruda, J.F. and Zon, L.I., Dissecting hematopoiesis and disease using the zebrafish, 1-15, Copyright (1999) with permission from Elsevier. Full text @ Dev. Biol.