Ferreira Daniela Cristina, Oliveira Claudio, Foresti Fausto
Departamento de Morfologia; Instituto de Biociência; Universidade Estadual Paulista; Botucatu, SP Brazil.
Mob Genet Elements. 2011 Jul;1(2):103-106. doi: 10.4161/mge.1.2.17450. Epub 2011 Jul 1.
Eight restriction enzymes were used in the prospection and isolation of repetitive sequences in the genome of the catfish Hisonotus leucofrenatus, a siluriform fish species that presents a large heterochromatic block in the W chromosome. In the tested enzymes, only the BamHI enzyme revealed a distinct band of 224 bp G+C value of 37%. In comparative analyses with sequences already available in the GenBank, the BamHI fragment sequence showed similarity with part of a Lepidoptera transposon. Fluorescent in situ hybridization (FISH) revealed that this sequence presents a dispersed pattern in the genome of H. leucofrenatus, forming clusters in some chromosome pairs in the pericentromeric region, which frequently are rich in constitutive heterochromatin. Based on the analysis performed, it can be inferred that the HLBam fragment constitutes a genomically dispersed transposon type element. It can be considered that the findings in this study can contribute to a better understanding of the organization and distribution of transposable elements in the genome of teleost fish.
八种限制性内切酶被用于在鲶鱼（Hisonotus leucofrenatus）基因组中探测和分离重复序列，鲶鱼是一种鲇形目鱼类，其W染色体上存在一个大的异染色质块。在测试的酶中，只有BamHI酶显示出一条224 bp的独特条带，G+C值为37%。在与GenBank中已有序列的比较分析中，BamHI片段序列与一种鳞翅目转座子的部分序列相似。荧光原位杂交（FISH）显示，该序列在鲶鱼基因组中呈现分散模式，在一些染色体对的着丝粒区域形成簇，这些区域通常富含组成型异染色质。基于所进行的分析，可以推断HLBam片段构成一种基因组分散的转座子类型元件。可以认为，本研究中的发现有助于更好地理解硬骨鱼类基因组中转座元件的组织和分布。
