小山蛙和中国雨蛙的核型及其C-带和银染的研究

Study on karyotypes C-banding and Ag-NORs of Rana minimus and Hyla chinensis from Fuzhou

采用骨骼细胞直接制备染色体标本法和BSG及Ag-NORs显带技术,研究了小山蛙(Rana minimus)和中国雨蛙(Hyla chinensis)的常规核型、C-带和Ag-NORs。小山蛙2n=26,有5对大型和8对小型染色体。第6对染色体短臂近着丝点处具次缢痕,并为C-带染色阳性,银带显示此次缢痕处,即是标准NORs。C-带显现于几乎所有染色体的着丝点区,插入型C-带少且弱,无端位带。中国雨蛙2n=24,有6对大型和6对小型染色体。次缢痕在第10对染色体长臂上,亦为C-带染色阳性,并与银染显示的标准NORs相一致。C-带分析表明,亦以着丝点C-带为主,插入型C-带少,无端位带。本文初步讨论了蛙科和雨蛙科的核学特征以及它们间的演化关系。

Using bone marrow preparing chromosome method.BSG technique and a quick Ag-stained NORs method,the conventional,C-banded and Ag-stained karyotypes of Rana minimus Ting et Ts'ai and Hyla ckinensis Guenther were studied.The diploid number of R.minimus is 2n=26,consisting of 5 pairs of large and 8 pairsof small chromosomes.A secondary constriction is observed at a position near the centromere on the short arm of chromosome No.6 and it is also the position of the 'standard NORs' Chromosome C-banding shows that the heteroch.romations of R.minimimus are located in the centromeric and pericentrorneric regions,with comparatively few lightly-stained interstitial C-bands and no telomeric ones.And the secondary constriction is C-banding positively stained.H.chinensis has 24 chromosomes which divide into a group of 6 large pairs and a group of 6 small pairs.A secondary constriction appears at a position on the long arm of chromosome No.10.It is also the position of the 'standard NORs' and C-banding positively stained.The C-banding pattern is mainly composed of centiomeric C-bands with few interstitial ones and no telomeric ones.The karyotypic characters of Ranidae and Hylidae and the relationship to the evolution are also discussed.