线粒体端粒：六种四膜虫中重复端粒DNA序列的惊人多样性。

Mitochondrial telomeres: surprising diversity of repeated telomeric DNA sequences among six species of Tetrahymena.

作者信息

Morin G B, Cech T R

机构信息

Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215.

出版信息

Cell. 1988 Feb 12;52(3):367-74. doi: 10.1016/s0092-8674(88)80029-1.

DOI:10.1016/s0092-8674(88)80029-1

PMID:3125982

Abstract

The DNA sequences at the ends of the linear mtDNA of 6 species of Tetrahymena encompassing 13 strains were determined. All the strains have variable numbers of a tandemly repeated DNA sequence, 31 bp to 53 bp in size, at their mtDNA termini. Based upon the size and nucleotide sequence of the terminal repeats, the telomeres can be separated into four classes. T. pigmentosa, hyperangularis, and hegewischi have different telomeric repeats on the two ends of their mtDNAs. The only conserved feature of the mtDNA termini is the presence of tandem repeats. The function of the repeats might be to promote unequal crossing over during recombination, thereby overcoming the problem of telomere replication for these linear DNAs.

摘要

测定了包含13个菌株的6种四膜虫线性线粒体DNA（mtDNA）末端的DNA序列。所有菌株的mtDNA末端都有数量可变的串联重复DNA序列，大小在31 bp至53 bp之间。根据末端重复序列的大小和核苷酸序列，端粒可分为四类。色素四膜虫、超角四膜虫和赫格维希四膜虫的mtDNA两端具有不同的端粒重复序列。mtDNA末端唯一保守的特征是存在串联重复序列。这些重复序列的功能可能是在重组过程中促进不等交换，从而克服这些线性DNA的端粒复制问题。