花背蟾蜍早期发育中内胚层细胞核的分化

Early Endodermal Nuclear Differentiation of Bufo Raddei Strauch

以细胞核移植的方法,探讨花背蟾蜍早期发育中内胚层细胞核的分化。实验按供体胚胎的不同发育时期分7组,并以囊胚期动物极区细胞核的移植作对照。结果表明:原肠晚期以前的内胚层细胞核与囊胚期动物极区细胞核一样,是尚未分化的,它们仍具有发育的全能性。从神经胚期开始,细胞核有了明显的分化,但这种分化是渐进的,至摄食期的蝌蚪仍有部分细胞核保持着促使卵子发育的功能。

In this paper, the early differentiation of the endoderm nuclei of Bufo raddei strauch during development has been studied by nuclear transplantation. According to the ages of the donor embryos,the experiments are classified into seven groups. The transplantation of blastula nuclei which are taken from the animal hemisphere into enucleated eggs is used for control. The experimental result shows that the developmental capacity of endodermal nuclei of late gastrula is about the same as that of the control.Their differentiation begins at the neurula stage but up to the swimming tadpole, a part of the endodermal nuclei still posses the capacity of development.