纤毛类低等无脊椎动物莱氏半眉虫多线染色体内部端粒重复序列的组织形式

The organization of internal telomeric repeats in the polytene chromosomes of the hypotrichous ciliate Stylonychia lemnae.

作者信息

Stoll S, Zirlik T, Maercker C, Lipps H J

机构信息

Medizinisch-Naturwissenschaftliches Forschungszentrum, Universität Tübingen, Germany.

出版信息

Nucleic Acids Res. 1993 Apr 25;21(8):1783-8. doi: 10.1093/nar/21.8.1783.

DOI:10.1093/nar/21.8.1783

PMID:8493097

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC309415/

Abstract

There exist about 1000-1500 internal telomeric sequences per haploid genome in the polytene chromosomes of the hypotrichous ciliate Stylonychia lemnae. All these telomeric repeats are contained in a very conserved element. This element consists of two 2 kb direct repeats flanking a 2.6 kb sequence. Immediately adjacent to one of the repeats a 18mer C4A4C4A4C2 telomeric sequence is localized. Sequences homologous to macronuclear DNA follow 180 bp downstream of the C4A4-bloc. These macronuclear homologous sequences are flanked by the second direct repeat. The possible origin and function of these telomere containing elements is discussed.

摘要

在纤毛虫纲的绿草履虫的多线染色体中，单倍体基因组每条染色体大约存在1000 - 1500个内部端粒序列。所有这些端粒重复序列都包含在一个非常保守的元件中。该元件由两个2kb的正向重复序列组成，中间夹着一个2.6kb的序列。紧邻其中一个重复序列定位着一个18聚体C4A4C4A4C2端粒序列。与大核DNA同源的序列位于C4A4片段下游180bp处。这些大核同源序列两侧是第二个正向重复序列。本文讨论了这些含端粒元件的可能起源和功能。