泉水鱼的细胞遗传学分析

Cytogenetic Analysis of Pseudogyrinocheilus prochilus

以泉水鱼(Pseudogyrinocheilus prochilus)的肾为材料,采用体内注射植物血球凝集素(PHA)和秋水仙素、肾组织细胞短期培养、常规空气干燥法制备泉水鱼染色体标本,对其核型进行分析。以泉水鱼外周血细胞为样本,鸡(Gallus gallus)血细胞DNA含量(2.50 pg/2c,2c指二倍体)为标准,用流式细胞仪测定了泉水鱼的DNA含量。结果表明:(1)泉水鱼的染色体数量为2n=50,核型公式为12m+14sm+14st+10t,总臂数NF=76,未发现性别相关的异型染色体;(2)泉水鱼的DNA含量为鸡血对照的(1.05±0.04)倍,其绝对DNA含量为(2.62±0.10)pg/2c。泉水鱼的染色体数目和DNA含量显示出二倍体的特征。

The chromosome number and karyotype of Pseudogyrinocheilus prochilus were analyzed using a routine method including intraperitoneal injection of phyohemagglutinin（PHA） and colchicine, cultivation invivo, and slides preparation with air-drying. Erythrocyte nuclear DNA content of P. prochilus was determined by using a flow cytometer（Beckman Coulter Inc., USA） with the chicken（Gallus gallus） erythrocytes（their DNA content is 2.50 pg/2c） serving as reference cells. The results showed that the diploid chromosome number of P. prochilus was 2n = 50, and the karyotype of this species was 2n = 12 m ＋ 14 sm ＋ 14 st ＋ 10 t, NF = 76（Fig. 1 and Table 1）. The heterosomes were not observed. The diploid cellular DNA content of P. prochilus was 2.62 ± 0.10 pg/2c（n = 20）, which was 1.05 ± 0.04 times of that of the chicken erythrocytes（Fig. 2）. The result of karyotype and DNA contents of P. prochilus indicate that P. prochilus is diploid.