Niehrs C, De Robertis E M
Molecular Biology Institute, University of California, Los Angeles 90024-1737.
EMBO J. 1991 Dec;10(12):3621-9. doi: 10.1002/j.1460-2075.1991.tb04928.x.
We have injected XIHbox 6 mRNA together with the lineage tracer colloidal gold into individual dorso-anterior blastomeres of the 32-cell stage Xenopus embryo and analyzed their cell fate during embryogenesis. While the developing tadpoles appeared entirely normal, the fate of the progeny of the injected blastomere was altered. In the brain injected cells failed to differentiate terminally, as indicated by a loss of labeled cranial nerves. Differentiation of spinal nerves remained unaffected. Fate change in the CNS occurred at about the time of normal XIHbox 6 protein expression. In addition, progeny of injected blastomeres gained head epidermal fate and lost anterior notochord fate as a result of altered cell migrations during gastrulation. The results show that a homeodomain protein is capable of altering cell fate in a position-specific and cell-autonomous manner in Xenopus embryos. The experimental approach used here should be applicable to other molecules specifying cell fate.
我们将XIHbox 6信使核糖核酸与谱系示踪剂胶体金一起注射到32细胞期非洲爪蟾胚胎的单个背侧前体卵裂球中，并在胚胎发育过程中分析它们的细胞命运。虽然发育中的蝌蚪看起来完全正常，但注射了卵裂球的后代的命运发生了改变。在大脑中，注射的细胞未能终末分化，如标记的颅神经缺失所示。脊神经的分化仍未受影响。中枢神经系统中的命运变化大约发生在正常XIHbox 6蛋白表达的时候。此外，由于原肠胚形成过程中细胞迁移的改变，注射卵裂球的后代获得了头部表皮命运并失去了前脊索命运。结果表明，一种同源结构域蛋白能够以位置特异性和细胞自主的方式改变非洲爪蟾胚胎中的细胞命运。这里使用的实验方法应该适用于其他指定细胞命运的分子。
