Santos Sara, Chaves Raquel, Adega Filomena, Bastos Estela, Guedes-Pinto Henrique
Department of Genetics and Biotechnology, Centre of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, P-5001-801 Vila Real, Portugal.
J Hered. 2006 Mar-Apr;97(2):114-8. doi: 10.1093/jhered/esj016. Epub 2006 Feb 9.
Most mammalian chromosomes have satellite DNA sequences located at or near the centromeres, organized in arrays of variable size and higher order structure. The implications of these specific repetitive DNA sequences and their organization for centromere function are still quite cloudy. In contrast to most mammalian species, the domestic cat seems to have the major satellite DNA family (FA-SAT) localized primarily at the telomeres and secondarily at the centromeres of the chromosomes. In the present work, we analyzed chromosome preparations from a fibrosarcoma, in comparison with nontumor cells (epithelial tissue) from the same individual, by in situ hybridization of the FA-SAT cat satellite DNA family. This repetitive sequence was found to be amplified in the cat tumor chromosomes analyzed. The amplification of these satellite DNA sequences in the cat chromosomes with variable number and appearance (marker chromosomes) is discussed and might be related to mitotic instability, which could explain the exhibition of complex patterns of chromosome aberrations detected in the fibrosarcoma analyzed.
大多数哺乳动物的染色体在着丝粒处或其附近含有卫星DNA序列，这些序列以大小可变的阵列和更高阶结构组织起来。这些特定的重复DNA序列及其组织方式对着丝粒功能的影响仍然相当模糊。与大多数哺乳动物物种不同，家猫似乎主要在染色体的端粒处，其次在着丝粒处定位了主要的卫星DNA家族（FA-SAT）。在本研究中，我们通过FA-SAT猫卫星DNA家族的原位杂交，分析了来自纤维肉瘤的染色体标本，并与来自同一个体的非肿瘤细胞（上皮组织）进行了比较。在分析的猫肿瘤染色体中发现了这种重复序列的扩增。讨论了猫染色体中这些卫星DNA序列的扩增，其数量和外观可变（标记染色体），这可能与有丝分裂不稳定性有关，这可以解释在分析的纤维肉瘤中检测到的复杂染色体畸变模式的表现。
