Pyati Ujwal J, Webb Ashley E, Kimelman David
Department of Biochemistry, University of Washington, Seattle, WA 98195-7350, USA.
Development. 2005 May;132(10):2333-43. doi: 10.1242/dev.01806. Epub 2005 Apr 13.
Bone morphogenetic protein (Bmp) signaling is crucial for the formation and patterning of zebrafish ventral and posterior mesoderm. Mutants defective in the Bmp pathway have expanded trunk muscle, abnormal tails and severely impaired development of ventral mesodermal derivatives such as vasculature, blood and pronephros. As Bmps continue to be expressed in the ventral and posterior mesoderm after gastrulation, it is likely that Bmp signaling continues to play an important developmental role during outgrowth of the posterior body. However, because Bmp signaling plays an essential role during the gastrula stages, it has not been possible with mutants or standard disruption techniques to determine the later functions of the Bmp pathway. To study the role of Bmp signaling in the ventral and posterior mesoderm during trunk and tail outgrowth, we generated a transgenic zebrafish line containing a heatshock-inducible dominant-negative Bmp receptor-GFP fusion. Our data show that Bmps are important for tail organizer formation and for patterning the ventral mesoderm during early gastrulation. However, from mid-gastrulation to the early somitogenesis stages, Bmp signaling is important for ventral tail fin development and for preventing secondary tail formation. We conclude that the role of Bmp signaling in the ventral and posterior mesoderm changes as gastrulation proceeds.
骨形态发生蛋白（Bmp）信号传导对于斑马鱼腹侧和后侧中胚层的形成及模式化至关重要。Bmp信号通路存在缺陷的突变体具有扩展的躯干肌肉、异常的尾巴，并且腹侧中胚层衍生物（如脉管系统、血液和前肾）的发育严重受损。由于原肠胚形成后Bmps仍在腹侧和后侧中胚层中表达，Bmp信号传导在后侧身体生长过程中可能继续发挥重要的发育作用。然而，由于Bmp信号传导在原肠胚阶段发挥着重要作用，利用突变体或标准破坏技术无法确定Bmp信号通路的后期功能。为了研究Bmp信号传导在躯干和尾巴生长过程中在腹侧和后侧中胚层中的作用，我们构建了一个含有热休克诱导型显性负性Bmp受体-GFP融合蛋白的转基因斑马鱼品系。我们的数据表明，Bmps对于尾组织者的形成以及原肠胚早期腹侧中胚层的模式化很重要。然而，从原肠胚中期到早期体节形成阶段，Bmp信号传导对于腹侧尾鳍发育以及防止次生尾的形成很重要。我们得出结论，随着原肠胚形成的进行，Bmp信号传导在腹侧和后侧中胚层中的作用发生了变化。
