Instituto de Estudos Costeiros, Universidade Federal do Pará, Bragança, Pará, Brazil.
Universidade Federal Rural da Amazônia, Parauapebas, Pará, Brazil.
PeerJ. 2024 Mar 20;12:e16924. doi: 10.7717/peerj.16924. eCollection 2024.
The main cytogenetic studies of the Characidae family comprise the genera and involving the use of repetitive DNA probes. However, for the microsatellite classes, studies are still scarce and the function of these sequences in the genome of these individuals is still not understood. Thus, we aimed to analyze and compare the distribution of microsatellite sequences in the species and .
We collected biopsies from the fins of and to perform cell culture, followed by chromosome extraction, and mapped the distribution of 14 microsatellites by FISH in both species.
The diploid number observed for both species was 2n = 50, with an acrocentric B microchromosome in and a metacentric B chromosome in . Regarding FISH, 11 probes hybridized in the karyotype of mainly in centromeric regions, and 13 probes hybridized in , mainly in telomeric regions, in addition to a large accumulation of microsatellite hybridization on its B chromosome.
Comparative FISH mapping of 14 microsatellite motifs revealed different patterns of distribution both in autosomes and supernumerary chromosomes of and , suggesting independent evolutionary processes in each of these species, representing excellent data on chromosome rearrangements and cytotaxonomy.
关于慈鲷科鱼类的主要细胞遗传学研究涉及使用重复 DNA 探针的 和 属。然而，对于微卫星类，研究仍然很少，这些序列在这些个体基因组中的功能仍不清楚。因此，我们旨在分析和比较 和 物种中微卫星序列的分布。
我们从 和 鳍中采集活检样本进行细胞培养，然后提取染色体，并通过 FISH 在这两个物种中定位 14 个微卫星。
两个物种的二倍体数均为 2n = 50， 在 中具有近端着丝粒 B 微染色体， 在 中具有着丝粒 B 染色体。关于 FISH，11 个探针在 的染色体组型中主要在着丝粒区域杂交，而 13 个探针主要在端粒区域杂交，此外，其 B 染色体上还存在大量微卫星杂交。
14 个微卫星基序的比较 FISH 图谱显示， 在常染色体和超数染色体中的分布模式不同，这表明这两个物种都经历了独立的进化过程，为染色体重排和细胞分类学提供了极好的数据。
