da Silva Marcelo J, de Araújo Vieira Ana P, Galvão Cipriano Flávia M, Dos Santos Cândido Maria R, de Oliveira Edivaldo H C, Gimenez Pinheiro Tamaris, da Silva Edson L
Cytogenet Genome Res. 2020;160(2):94-99. doi: 10.1159/000506140. Epub 2020 Feb 15.
In this study, we analyzed the karyotype of Salvator merianae (Teiidae) from the Brazilian semiarid region using different cytogenetic markers. Chromosomes were examined by classical (Giemsa and AgNOR staining) and molecular (FISH with ribosomal, telomeric, and microsatellite probes) cytogenetic approaches. S. merianae showed a diploid chromosome number of 2n = 38 (10 biarmed macrochromosomes + 28 microchromosomes). No sex-linked chromosome heteromorphisms were observed. Clusters of 18S/28S rDNA were localized in the terminal region of the long arm of pair 2. In addition to the typical telomeric signals, (TTAGGG)n repeats were detected in the pericentromeric region of some macrochromosome pairs, which might indicate the occurrence of chromosomal rearrangements via chromosome fusions. Hybridization signals of the microsatellite probes (GA)n, (GAA)n, and (GAG)n were uniformly distributed across all chromosomes, while (CA)n, (CAA)n, and (CAC)n produced brighter signals in the telomeric and pericentromeric regions of specific chromosome pairs. The comparison with previous studies demonstrates that, despite the wide distribution of S. merianae, the macrostructure organization of the karyotype remained unchanged, showing stability in diploid number and chromosome morphology.
在本研究中，我们使用不同的细胞遗传学标记分析了来自巴西半干旱地区的中美鞭尾蜥（鞭尾蜥科）的核型。通过经典（吉姆萨和银染核仁组织区染色）和分子（用核糖体、端粒和微卫星探针进行荧光原位杂交）细胞遗传学方法对染色体进行了检查。中美鞭尾蜥的二倍体染色体数为2n = 38（10条双臂大染色体 + 28条小染色体）。未观察到性连锁染色体多态性。18S/28S rDNA簇定位于第2对染色体长臂的末端区域。除了典型的端粒信号外，在一些大染色体对的着丝粒周围区域检测到了（TTAGGG）n重复序列，这可能表明通过染色体融合发生了染色体重排。微卫星探针（GA）n、（GAA）n和（GAG）n的杂交信号均匀分布在所有染色体上，而（CA）n、（CAA）n和（CAC）n在特定染色体对的端粒和着丝粒周围区域产生更亮的信号。与先前研究的比较表明，尽管中美鞭尾蜥分布广泛，但其核型的宏观结构组织保持不变，在二倍体数目和染色体形态上表现出稳定性。
