利用 FISH 和 Southern 杂交技术对扁形动物和棘头动物的端粒进行分析。

Telomere analysis of platyhelminths and acanthocephalans by FISH and Southern hybridization.

机构信息

Parasitological Institute, Slovak Academy of Sciences, Hlinkova 3, 04001 Kosice, Slovakia.

出版信息

Genome. 2009 Nov;52(11):897-903. doi: 10.1139/g09-063.

PMID:19935913

Abstract

We examined the composition of telomeres in chromosomes of parasitic worms, representatives of the flatworm groups Monogenea and Cestoda (Platyhelminthes), and thorny-headed worms (Syndermata: Acanthocephala) by fluorescence in situ hybridization (FISH) with different telomeric repeat probes. Our results show that the (TTAGGG)n sequence, supposed to be the ancestral telomeric repeat motif of Metazoa, is conserved in Monogenea (Paradiplozoon homoion) and Cestoda (Caryophyllaeus laticeps, Caryophyllaeides fennica, and Nippotaenia mogurndae) but not in Acanthocephala (Pomphorhynchus laevis and Pomphorhynchus tereticollis). In the Pomphorhynchus species, no hybridization signals were obtained with the "nematode" (TTAGGC)n, "arthropod" (TTAGG)n, and bdelloid (TGTGGG)n telomeric probes using FISH with their chromosomes and Southern hybridization with P. laevis DNA. Therefore, we suggest that parasitic Acanthocephala have evolved yet unknown telomeric repeat motifs or different mechanisms of telomere maintenance.

摘要

我们通过荧光原位杂交（FISH）用不同的端粒重复探针检查了寄生蠕虫（扁形动物门的单殖吸虫纲和绦虫纲）和棘头虫（Syndermata：棘头动物门）染色体中端粒的组成。我们的结果表明，（TTAGGG）n 序列被认为是后生动物的祖先端粒重复基序，在单殖吸虫纲（Paradiplozoon homoion）和绦虫纲（Caryophyllaeus laticeps、Caryophyllaeides fennica 和 Nippotaenia mogurndae）中是保守的，但在棘头动物门中不是（Pomphorhynchus laevis 和 Pomphorhynchus tereticollis）。在 Pomphorhynchus 物种中，用 FISH 与它们的染色体和 Southern 杂交与 P. laevis DNA 进行杂交，用“线虫”（TTAGGC）n、“节肢动物”（TTAGG）n 和蛭形轮虫（TGTGGG）n 端粒探针均未获得杂交信号。因此，我们认为寄生棘头动物已经进化出未知的端粒重复基序或不同的端粒维持机制。