Comparative analysis of the chromosomal and genomic organization of Ty1-copia-like retrotransposons in pteridophytes, gymnosperms and angiosperms
Comparative analysis of the chromosomal and genomic organization of Ty1-copia-like retrotransposons in pteridophytes, gymnosperms and angiosperms
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DOI：
10.1023/a:1005797222148
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发表时间：
1997-01-01
影响因子：
5.1
通讯作者：
Schmidt, T
中科院分区：
文献类型：
--
作者：
Brandes, A;HeslopHarrison, JS;Schmidt, T
我们已经调查了物理分布的逆转录酶基因的Ty 1 copia样逆转录转座因子从12种植物属于不同的细分染色体制备原位杂交。Ty 1-copia样元件表现出不同的和非随机的杂交模式。洋葱、甜菜、油菜、甘蓝、白狼尾草、湿地松、卷柏、蚕豆和野豌豆的大部分染色体呈分散分布，在某些区域杂交减少或在其他区域有弱的聚类。减少杂交主要发生在着丝粒区，核仁组织区和已知的主要由串联重复序列组成的区域。在蕨类植物Pteriscretica的逆转录分子显示了一个分散的基因组组织与集群在一些染色体区域和整个染色体显示很少的信号。在拟南芥和鹰嘴豆中，Ty 1-copia样元件被发现在簇中的paracentromeric异染色质，一种新的组织中的重复元件，拟南芥。从A. thaliana和Beta vulgaris。与其他植物Ty 1-copia-like元件的比对结果显示，它们之间的亲缘关系存在较大差异，表明了逆转录酶基因分析在系统发育和生物多样性研究中的价值。
We have investigated the physical distribution of the reverse transcriptase genes of Ty1-copia-like retrotransposable elements from 12 plant species belonging to different subdivisions by hybridization in situ on chromosome preparations. Ty1-copia-like elements showed different and non-random hybridization patterns. A dispersed distribution throughout most of the chromosomes with reduced hybridization at some regions or with some weak clustering al other regions was found in Allium cepa, Beta vulgaris, Brassica campestris, Brassica oleracea, Pennisetum glaucum, Pinus elliottii, Selaginella apoda, Vicia faba and Vicia narbonensis. Reduced hybridization occured mainly at centromeric regions, nucleolus-organizing regions and regions known to be mainly composed of tandemly repeated sequences. In the fern Pteris cretica the retroelements showed a dispersed genomic organization with clustering at some chromosomal regions and whole chromosomes showing little signal. In Arabidopsis thaliana and Cicer arietinum, Ty1-copia-like elements were found in clusters at the paracentromeric heterochromatin, a novel organization for a repetitive element in A, thaliana. New retroelement families were isolated from A. thaliana and from Beta vulgaris. Alignment of the deduced peptide sequences with Ty1-copia-like elements from other plants showed considerable divergence which was used to calculate their relationships, indicating the value of reverse transcriptase gene analysis in phylogenetic and biodiversity studies.