嗜热四膜虫大核DNA中腺嘌呤甲基化的位置效应

Position effect for adenine methylation in the macronuclear DNA of Tetrahymena.

作者信息

Van Nuland T A, Capowski E E, Karrer K M

机构信息

Department of Biology, Marquette University, Milwaukee, WI 53233, USA.

出版信息

Gene. 1995 May 19;157(1-2):235-7. doi: 10.1016/0378-1119(94)00546-5.

DOI:10.1016/0378-1119(94)00546-5

PMID:7607498

Abstract

The macronucleus of the ciliate Tetrahymena contains about 45 copies of the genome. The fraction of the molecules on which an adenine residue is modified to N6-methyladenine is characteristic of the specific site, and consistent between clones. A fragment of DNA containing a site that is uniformly methylated on the macronuclear chromosome was moved to a new location on the extrachromosomal rDNA. The methylation pattern of the fragment on the rDNA was different from that on the chromosome. The data suggest that DNA sequence is not sufficient to determine the level of methylation.

摘要

纤毛虫四膜虫的大核包含约45个基因组拷贝。腺嘌呤残基被修饰为N6-甲基腺嘌呤的分子比例是特定位点的特征，并且在克隆之间是一致的。一段在大核染色体上被均匀甲基化的DNA片段被转移到染色体外rDNA的一个新位置。该片段在rDNA上的甲基化模式与在染色体上的不同。数据表明DNA序列不足以确定甲基化水平。