Mizuno T, Yamaha E, Kuroiwa A, Takeda H
Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan.
Mech Dev. 1999 Mar;81(1-2):51-63. doi: 10.1016/s0925-4773(98)00202-0.
To examine the nature of cytoplasm determinants for dorsal specification in zebrafish, we have developed a method in which we remove the vegetal yolk hemisphere of early fertilized eggs (vegetal removed embryos). When the vegetal yolk mass was removed at the 1-cell stage, the embryos frequently exhibited typical ventralized phenotypes: no axial structures developed. The frequency of dorsal defects decreased when the operation was performed at later stages. Furthermore, the yolk cell obtained from the vegetal-removed embryos lost the ability to induce goosecoid in normal blastomeres while the normal yolk cell frequently did so in normal and vegetal-removed embryos. These results suggested that the vegetal yolk cell mass contains the dorsal determinants, and that the dorsal-inducing ability of the yolk cell is dependent on the determinants.
为了研究斑马鱼中用于背侧特化的细胞质决定因子的性质，我们开发了一种方法，即去除早期受精卵的植物性卵黄半球（去除植物性卵黄的胚胎）。当在单细胞阶段去除植物性卵黄团时，胚胎经常表现出典型的腹侧化表型：没有发育出轴向结构。当在后期进行手术时，背侧缺陷的频率降低。此外，从去除植物性卵黄的胚胎中获得的卵黄细胞失去了在正常卵裂球中诱导 goosecoid 的能力，而正常卵黄细胞在正常和去除植物性卵黄的胚胎中经常能诱导。这些结果表明，植物性卵黄细胞团含有背侧决定因子，并且卵黄细胞的背侧诱导能力取决于这些决定因子。
