Chromosome spreading of associated transposable elements and ribosomal DNA in the fish Erythrinus erythrinus. Implications for genome change and karyoevolution in fish.
Chromosome spreading of associated transposable elements and ribosomal DNA in the fish Erythrinus erythrinus. Implications for genome change and karyoevolution in fish.
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DOI：
10.1186/1471-2148-10-271
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发表时间：
2010-09-06
影响因子：
3.4
通讯作者：
Bertollo LA
中科院分区：
文献类型：
--
作者：
Cioffi MB;Martins C;Bertollo LA
该鱼，Erythrinus corrinus，表现出种群间的多样性，有四个karyomorphs不同的染色体数目，染色体形态和异形性染色体。核型A的二倍体数为2n = 54，没有分化的性染色体。核型D在雌性中具有2n = 52条染色体，在雄性中具有2n = 51条染色体，并且它最可能通过多X1 X2 Y性染色体系统的分化而从核型A衍生。在这项研究中，我们分析了核型A和D的细胞遗传学方法来评估他们的进化关系。5S rDNA和Rex 3 non-LTR反转录转座子的分布在两种核型之间存在明显差异，而异染色质和18 S rDNA模式在它们之间没有发现变化。Rex 3在大多数染色体上呈分散分布。在核型A中，它只在两条端着丝粒染色体的着丝粒区室化分布。相比之下，在核型D中，Rex 3在女性的22条端着丝粒染色体和男性的21条中被发现。所有5S rDNA位点与Rex 3共定位，表明这些位点在基因组中相关。此外，起源的大型中部着丝粒Y染色体在核型D的中心融合突出的存在下，内部端粒位点和5S rDNA/Rex 3的网站在这条染色体上。我们证明了一些重复DNA（5SrDNA、Rex 3逆转录元件和（TTAGGG）n端粒重复序列）在大肠杆菌内部的进化分化中起着关键作用。阿奎里纳斯这些元素与该物种的核形态进化密切相关。我们的研究结果表明，染色体重排和基因组修饰是显着的事件，在这个鱼的进化过程中。我们检测到着丝粒融合，与多性染色体的分化在核型D，以及一个令人惊讶的增加相关的5S rDNA/Rex 3基因座，相反，核型A。在这个意义上，E。鱼是一个很好的模型系统，可以更好地理解鱼类巨大的基因组多样性背后的进化机制。这种生物体也有助于理解整个脊椎动物基因组的进化。
The fish, Erythrinus erythrinus, shows an interpopulation diversity, with four karyomorphs differing by chromosomal number, chromosomal morphology and heteromorphic sex chromosomes. Karyomorph A has a diploid number of 2n = 54 and does not have differentiated sex chromosomes. Karyomorph D has 2n = 52 chromosomes in females and 2n = 51 in males, and it is most likely derived from karyomorph A by the differentiation of a multiple X1X2Y sex chromosome system. In this study, we analyzed karyomorphs A and D by means of cytogenetic approaches to evaluate their evolutionary relationship. Conspicuous differences in the distribution of the 5S rDNA and Rex3 non-LTR retrotransposon were found between the two karyomorphs, while no changes in the heterochromatin and 18S rDNA patterns were found between them. Rex3 was interstitially dispersed in most chromosomes. It had a compartmentalized distribution in the centromeric regions of only two acrocentric chromosomes in karyomorph A. In comparison, in karyomorph D, Rex3 was found in 22 acrocentric chromosomes in females and 21 in males. All 5S rDNA sites co-localized with Rex3, suggesting that these are associated in the genome. In addition, the origin of the large metacentric Y chromosome in karyomorph D by centric fusion was highlighted by the presence of internal telomeric sites and 5S rDNA/Rex3 sites on this chromosome. We demonstrated that some repetitive DNAs (5S rDNA, Rex3 retroelement and (TTAGGG)n telomeric repeats) were crucial for the evolutionary divergence inside E. erythrinus. These elements were strongly associated with the karyomorphic evolution of this species. Our results indicate that chromosomal rearrangements and genomic modifications were significant events during the course of evolution of this fish. We detected centric fusions that were associated with the differentiation of the multiple sex chromosomes in karyomorph D, as well as a surprising increase of associated 5S rDNA/Rex3 loci, in contrast to karyomorph A. In this sense, E. erythrinus emerges as an excellent model system for better understanding the evolutionary mechanisms underlying the huge genome diversity in fish. This organism can also contribute to understanding vertebrate genome evolution as a whole.
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影响因子：
1.7
作者：
Jurka, J;Kapitonov, VV;Walichiewicz, J
通讯作者：
Walichiewicz, J
影响因子：
1.6
作者：
Chew, JSK;Oliveira, C;Dobson, MJ
通讯作者：
Dobson, MJ
影响因子：
1.7
作者：
Gross, M. C.;Schneider, C. H.;Feldberg, E.
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Feldberg, E.
影响因子：
3.8
作者：
Bertollo, LAC;Oliveira, C;Fenocchio, AS
通讯作者：
Fenocchio, AS
影响因子：
4
作者：
Barske, Lindsey A.;Capel, Blanche
通讯作者：
Capel, Blanche