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文章对二倍体大鳞副泥鳅♀×四倍体泥鳅♂杂交后代的染色体进行Ag-NORs、CMA3/DA/DAPI及FISH等系列研究。结果表明,①在对照组泥鳅×泥鳅(2n×2n)杂交后代的间期核和中期分裂相中最高银染点数为2个,杂交组2n×4n杂种后代的间期核和中期分裂相中最高银染点数为3个;②在对照组2n×2n杂交后代有丝分裂中期分裂相中,2条中部着丝粒染色体(M)的端部区域显示有明亮的CMA3阳性部位,杂交组2n×4n杂种后代有丝分裂中期分裂相中3条中部着丝粒染色体(M)的端部区域显示明亮的CMA3阳性部位;③应用荧光原位杂交(FISH)技术可以将核糖体5.8S+28S rDNA清楚地定位在杂交后代中期染色体中部着丝粒染色体(M)的端部区域。在对照组2n×2n中期染色体上可以检测到二簇杂交信号,而在杂交组后代中期染色体上可以检测到三簇杂交信号。通过Ag-NORs、CMA3/DA/DAPI荧光显带及核糖体5.8S+28S rDNA的FISH定位在杂交后代得到的NORs位点相吻合,位点数目为3个。该结果为杂种后代提供了直接的三倍体细胞遗传学证据。
In this paper, Ag-NORs, CMA3 / DA / DAPI and FISH were used to study the chromosomes of hybrid diploid loach ♀ × tetraploid loach ♂. The results showed that ① the highest number of silver stains in interphase and metaphase of the hybrid loach × loach (2n × 2n) hybrids was 2 in the control group, and the interphase and metaphase of the 2n × 4n hybrid progenies The highest number of silver stains was 3; ② In the mitotic metaphase of the 2n × 2n hybrids in the control group, the end regions of the two centromere chromosomes (M) showed a bright CMA3-positive site, and the 2n × 4n The end regions of the three centromeric chromosomes (M) in the metaphase mitosis of hybrid progenies showed bright CMA3-positive sites; ③ The ribosomal 5.8S + 28S rDNA was clearly localized by fluorescence in situ hybridization (FISH) Mid-centromeric chromosome centromeric chromosome (M) end region in hybrid progeny. Two clusters of hybridization signals could be detected on the 2n × 2n metaphase chromosome of the control group, while three clusters of hybridization signals could be detected on the metaphase chromosomes of the hybrid group. FISH mapping of Ag-NORs, CMA3 / DA / DAPI fluorescent bands and ribosomal 5.8S + 28S rDNA coincided with the NORs sites of the hybrid progeny with 3 loci. This result provides direct triploid cytogenetic evidence for hybrid offspring.