大熊猫(Ailuropoda melanolenca)显带染色体的研究

STUDY ON THE BANDED CHROMOSOMES OF THE GIANT PANDA(Ailuropoda melanolenca)

大熊猫系我国特产的世界珍稀动物,素有“活化石”和“国宝”之称。限于材料来源,虽有核型的少数报道(邓承宗等,1980;陈文元等,1984;Newnham et al.,1966),但研究尚不够深入。1980年,Wurster-Hill和Bush首先报道了大熊猫(♂)的显带核型,并与杂交熊等比较,探讨了大熊猫的分类地位。本文对四只大熊猫的G带、C带核型和Ag-NORs作了分析,绘制了G带核型模式图,并提出了某些商榷的意见。

The banded chromosomes G-banding,C-banding and Ag-staining technique of the giant panda(Ailuropoda melanolenca)have been studied.The results are as follows.1.The diploid chromosome number is 42 in the giant panda.The distinctive G-banding patterns are clearly discernible in almost every chromosome.The banded idiogram based on the analysis of the banded chromosomes has been determined.2.There is little heterochromatin revealed by C-banding.All the chromosomes have centromeric heterochromatin.The maker chromosomes(No.17)have well-developed C bands showing the most prominent heterochromatin.3.In the karyotype of the giant panda,Ag-NORs is the only the secondary constitution of the maker chromosomes.The number of Ag-NORs varies among the different individuals or mctaphase analyzed.The satellite association has been demonstrated based on the fusion of Ag-NORs.Besides,later separation of centromere was noticed in the maker chromosomes during anaphase of miis.