家蚕W染色体上类copia反转录转座元件Yokozuna的分子结构

Molecular structure of the copia-like retrotransposable element Yokozuna on the W chromosome of the silkworm, Bombyx mori.

作者信息

Ohbayashi F, Shimada T, Sugasaki T, Kawai S, Mita K, Oshiki T, Abe H

机构信息

Department of Biological Production, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Japan.

出版信息

Genes Genet Syst. 1998 Dec;73(6):345-52. doi: 10.1266/ggs.73.345.

DOI:10.1266/ggs.73.345

PMID:10333565

Abstract

We discovered a novel retrotransposable element, designated Yokozuna, on the W chromosome of Bombyx mori. The size of this element is 4738 bp, including a 208-bp long terminal repeat (LTR) on one side and a 183-bp LTR on the other. This retrotransposable element is flanked by a 5-bp target site duplication, TAATT. Yokozuna contains a single long open reading frame (ORF) and the whole deduced amino acid sequence of ORF reveals strong homology with copia of Drosophila. Moreover, an alignment analysis of the reverse transcriptase (RT) sequences suggested that the Yokozuna element is the first Bombyx retrotransposable element belonging to the Ty1-copia group. The number of Yokozuna per haploid genome is approximately four copies. Although Yokozuna was discovered on the W chromosome, it is not specific for the W chromosome.

摘要

我们在家蚕的W染色体上发现了一种新型反转录转座元件，命名为横纲（Yokozuna）。该元件大小为4738 bp，一侧有一个208 bp的长末端重复序列（LTR），另一侧有一个183 bp的LTR。这种反转录转座元件两侧有一个5 bp的靶位点重复序列TAATT。横纲包含一个单一的长开放阅读框（ORF），ORF推导的完整氨基酸序列与果蝇的copia显示出很强的同源性。此外，反转录酶（RT）序列的比对分析表明，横纲元件是家蚕中第一个属于Ty1-copia组的反转录转座元件。每个单倍体基因组中横纲的数量约为4个拷贝。虽然横纲是在W染色体上发现的，但它并非W染色体所特有。