Nasevicius A, Larson J, Ekker S C
Arnold and Mabel Beckman Center for Transposon Research, Department of Genetics, University of Minnesota, 6-160 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, USA.
Yeast. 2000 Dec;17(4):294-301. doi: 10.1002/1097-0061(200012)17:4<294::AID-YEA54>3.0.CO;2-5.
Angiogenesis is a fundamental vertebrate developmental process that requires signalling by the secreted protein vascular endothelial growth factor-A (VEGF-A). VEGF-A functions in the development of embryonic structures, during tissue remodelling and for the growth of tumour-induced vasculature. The study of the role of VEGF-A during normal development has been significantly complicated by the dominant, haplo-insufficient nature of VEGF-A-targeted mutations in mice. We have used morpholino-based targeted gene knock-down technology to generate a zebrafish VEGF-A morphant loss of function model. Zebrafish VEGF-A morphant embryos develop with an enlarged pericardium and with major blood vessel deficiencies. Morphological assessment at 2 days of development indicates a nearly complete absence of both axial and intersegmental vasculature, with no or reduced numbers of circulating red blood cells. Molecular analysis using the endothelial markers fli-1 and flk-1 at 1 day of development demonstrates a fundamental distinction between VEGF-A requirements for axial and intersegmental vascular structure specification. VEGF-A is not required for the initial establishment of axial vasculature patterning, whereas all development of intersegmental vasculature is dependent on VEGF-A signalling. The zebrafish thus serves as a quality model for the study of conserved vertebrate angiogenesis processes during embryonic development.
血管生成是脊椎动物的一个基本发育过程，需要分泌蛋白血管内皮生长因子-A（VEGF-A）发出信号。VEGF-A在胚胎结构发育、组织重塑过程以及肿瘤诱导的脉管系统生长中发挥作用。在小鼠中，VEGF-A靶向突变具有显性、单倍体不足的特性，这使得研究VEGF-A在正常发育过程中的作用变得极为复杂。我们利用基于吗啉代的靶向基因敲低技术构建了斑马鱼VEGF-A功能缺失模型。斑马鱼VEGF-A功能缺失的胚胎发育时心包扩大，主要血管存在缺陷。发育2天时的形态学评估显示，轴向和节间脉管系统几乎完全缺失，循环红细胞数量极少或没有。在发育1天时使用内皮标记物fli-1和flk-1进行分子分析，结果表明VEGF-A在轴向和节间血管结构形成方面的需求存在根本差异。轴向脉管系统模式的初始建立不需要VEGF-A，而节间脉管系统的所有发育都依赖于VEGF-A信号传导。因此，斑马鱼是研究胚胎发育过程中保守的脊椎动物血管生成过程的优质模型。
