Lee R K, Stainier D Y, Weinstein B M, Fishman M C
Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, 02129.
Development. 1994 Dec;120(12):3361-6. doi: 10.1242/dev.120.12.3361.
We have examined the zebrafish embryo to ascertain the location of endocardial and myocardial progenitors prior to gastrulation, in an attempt to define the earliest stages of cardiac patterning. Currently there is uncertainty as to the spatial and lineage relationship of the progenitors for these two phenotypically distinct cell types that form the two concentric layers of the primitive heart tube. By single-cell injection and tracking, we distinguish a region in the early and midblastula which has the properties of a heart field, in that it defines a zone of cardiac progenitors within which there is a spatial gradient of propensity to generate heart cells, and which regulates, in the sense of adapting to the transplantation of pluripotential cells. This zone extends from the future ventral axis dorsally along the margin, with cardiogenic propensity tapering off laterally and dorsally. Myocardial progenitors are spread throughout this region, but endocardial precursors are restricted to the ventral marginal region. The cardiovascular progeny of the ventral cells include, in addition to endocardium and myocardium, cells in the endothelium and blood.
我们研究了斑马鱼胚胎，以确定原肠胚形成之前心内膜和心肌祖细胞的位置，试图明确心脏模式形成的最早阶段。目前，对于形成原始心管两个同心层的这两种表型不同的细胞类型的祖细胞的空间和谱系关系尚不确定。通过单细胞注射和追踪，我们在囊胚早期和中期区分出一个具有心脏场特性的区域，即它定义了一个心脏祖细胞区域，在该区域内存在产生心脏细胞倾向的空间梯度，并且从适应多能细胞移植的意义上来说，它具有调节作用。这个区域从未来的腹轴向背侧沿着边缘延伸，心脏发生倾向在侧面和背侧逐渐减弱。心肌祖细胞分布在整个这个区域，但心内膜前体仅限于腹侧边缘区域。腹侧细胞的心血管后代除了心内膜和心肌外，还包括内皮细胞和血液中的细胞。
