Kokalj-Vokac N, Almeida A, Viegas-Péquignot E, Jeanpierre M, Malfoy B, Dutrillaux B
CNRS URA 620, Institut Curie, Section de Biologie, Paris, France.
Cytogenet Cell Genet. 1993;63(1):11-5. doi: 10.1159/000133492.
Azacytidine (ACR) is known to induce uncoiling and somatic association involving the constitutive heterochromatin of human chromosomes 1, 9, 15, and 16 and the Y. These regions are composed of alphoid and classical satellite DNA sequences. Using specific probes for chromosomes 1 and 16, we have performed two-color fluorescence in situ hybridization on human lymphocytes cultured in the presence of ACR. We demonstrate that for these two chromosomes (1) uncoiling and association specifically occur in classical satellite-containing regions at the first cell generation, (2) breakages also affect these regions, and (3) somatic recombinations occur between these regions and lead to translocations at the next cell generation. These results suggest that changes in methylation of repetitive DNA sequences are related to chromosomal instability occurring during cell transformation and tumorigenesis.
已知氮杂胞苷（ACR）可诱导解旋以及涉及人类1号、9号、15号和16号染色体以及Y染色体的组成型异染色质的体细胞关联。这些区域由α卫星DNA序列和经典卫星DNA序列组成。我们使用针对1号和16号染色体的特异性探针，对在ACR存在下培养的人类淋巴细胞进行了双色荧光原位杂交。我们证明，对于这两条染色体，（1）解旋和关联在第一代细胞中特异性地发生在含有经典卫星的区域，（2）断裂也影响这些区域，并且（3）这些区域之间发生体细胞重组并导致下一代细胞发生易位。这些结果表明，重复DNA序列甲基化的变化与细胞转化和肿瘤发生过程中出现的染色体不稳定性有关。
