A mutagenesis genetic screen to identify zebrafish embryos with defects in vasculature development

MARIANA MELANI; MISATO FUJITA; DANIEL CASTRANOVA; ANDREW DAVIS; ANIKET V. GORE; MATTHEW SWIFT; YOUNG RYUN-CHA; BRIGID D. LO; BRANT M. WEINSTEIN

San Francisco, California, USA

Congreso; Society for Developmental Biology 68th Annual Meeting; 2009

Society for Developmental Biology

The zebrafish Danio reiro is a powerful vertebrate model system to study developmentally regulated processes, such as the formation of the vascular tree. The vascular system of the zebrafish embryo forms by a combination of vasculogenic and angiogenic processes, mirroring the early vascular development of humans. Moreover, most of the genes currently known to act during embryonic vascular development are highly conserved in vertebrates. Zebrafish embryos develop externally, are optically transparent, and are produced in large clutches. All these advantages can be exploited to carry out genetic screens to look for mutants with defects in early stages of vascular development. We conducted an ENU mutagenesis to identify vascular-specific mutants in an F3 genetic screen. To facilitate the screening process, we used a stable germline transgenic, fli1-EGFPy1, that expresses enhanced green fluorescent protein in endothelial cells in vivo under the control of the fli1 promoter. The robust expression of EGFP in the vascular endothelium enabled us to screen visually for blood vessel patterning defects and changes in vasculogenesis at 4 days post-fertilization. We have found many new mutants with phenotypes that include vascular patterning defects, ectopic vessels, missing vessels, and vascular shunts. Genetic mapping and identification of the genes responsible for the mutant phenotypes will lead to increased understanding of the formation of the human vasculature as well as on the pathogenesis of numerous cardiovascular diseases.