Oliveira Sarah G, Cabral-de-Mello Diogo C, Moura Rita C, Martins Cesar
Morphology Department, Biosciences Institute, UNESP - São Paulo State University, Botucatu, SP 18618-970, Brazil.
Mol Cytogenet. 2013 Nov 29;6(1):54. doi: 10.1186/1755-8166-6-54.
With the aim to increase the knowledge on the evolution of coleopteran genomes, we investigated through cytogenetics and nucleotide sequence analysis Mariner transposons in three Scarabaeinae species (Coprophanaeus cyanescens, C. ensifer and Diabroctis mimas).
The cytogenetic mapping revealed an accumulation of Mariner transposon in the pericentromeric repetitive regions characterized as rich in heterochromatin and C0t-1 DNA fraction (DNA enriched with high and moderately repeated sequences). Nucleotide sequence analysis of Mariner revealed the presence of two major groups of Mariner copies in the three investigated coleoptera species.
The Mariner is accumulated in the centromeric area of the coleopteran chromosomes probably as a consequence of the absence of recombination in the heterochromatic regions. Our analysis detected high diversification of Mariner sequences during the evolutionary history of the group. Furthermore, comparisons between the coleopterans sequences with other insects and mammals, suggest that the horizontal transfer (HT) could have acted in the spreading of the Mariner in diverse non-related animal groups.
为了增加对鞘翅目基因组进化的了解，我们通过细胞遗传学和核苷酸序列分析，研究了三种金龟子亚科物种（蓝绿粪金龟、具角粪金龟和米马斯暗黑鳃金龟）中的水手转座子。
细胞遗传学图谱显示，水手转座子在着丝粒周围的重复区域积累，这些区域富含异染色质和C0t-1 DNA组分（富含高度和中度重复序列的DNA）。对水手转座子的核苷酸序列分析表明，在所研究的三种鞘翅目物种中存在两大类水手转座子拷贝。
水手转座子可能由于异染色质区域缺乏重组而积累在鞘翅目染色体的着丝粒区域。我们的分析检测到该类群进化历史中水手转座子序列的高度多样化。此外，鞘翅目序列与其他昆虫和哺乳动物序列的比较表明，水平转移可能在水手转座子在不同无关动物群体中的传播中发挥了作用。
