Yeast telomeric sequences function as chromosomal anchorage points in vivo
Yeast telomeric sequences function as chromosomal anchorage points in vivo
复制标题
DOI：
10.1093/emboj/16.3.523
复制
发表时间：
1997-02-03
期刊：
影响因子：
11.4
通讯作者：
Gartenberg, MR
中科院分区：
文献类型：
--
作者：
Mirabella, A;Gartenberg, MR
Site-specific recombination in Saccharomyces cerevisiae was used to generate non-replicative DNA rings containing yeast telomeric sequences, In topoisomerase mutants expressing Escherichia coli topoisomerase I, the rings adopted a novel DNA topology consistent with the ability of yeast telomeric DNA to block or retard the axial rotation of DNA, DNA fragments bearing portions of the terminal repeat sequence C-1-3 A/TG(1-3) were both necessary and sufficient to create a barrier to DNA rotation, Synthetic oligonucleotide sequences containing Rap1p binding sites, a well represented motif in naturally occurring C(1-3)A arrays, also conferred immobilization; mutant Rap1p binding sites and telomeric sequences from other organisms were not sufficient, DNA anchoring was diminished by addition of competing telomeric sequences, implicating a role for an as yet unidentified limiting trans-acting factor, Though Rap1p is a likely protein constituent of the DNA anchor, deletion of the non-essential C-terminal domain did not affect the topology of telomeric DNA rings, Similarly, disruption of SIR2, SIR3 and SIR4, genes which influence a variety of telomere functions in yeast, also had no effect, We propose that telomeric DNA supports the formation of a SIR-independent macromolecular protein-DNA assembly that hinders the motion of DNA because of its linkage to an insoluble nuclear structure, Potential roles for DNA anchoring in telomere biology are discussed.
