Mutations in POL1 increase the mitotic instability of tandem inverted repeats in Saccharomyces cerevisiae.
Mutations in POL1 increase the mitotic instability of tandem inverted repeats in Saccharomyces cerevisiae.
复制标题
POL1 的突变增加了酿酒酵母串联反向重复序列的有丝分裂不稳定性。
DOI：
10.1093/genetics/134.1.43
复制
发表时间：
1993
期刊：
影响因子：
3.3
通讯作者：
Fink,GR
中科院分区：
文献类型：
--
作者：
Ruskin,B;Fink,GR
30和80个碱基对单位长度的串联反向重复序列（TIR或发夹）在酵母（酿酒酵母）中是不稳定的。TIR不稳定性是由从染色体上去除部分或全部假定的发夹结构的缺失引起的。至少一个缺失端点总是在发夹的碱基处或附近，并且几乎所有修复的连接都发生在4至9个碱基对的短的直接序列重复内。我们称之为"发夹切除"的这种事件的频率受染色体位置、反向重复序列的长度和重复单元之间的距离的影响;将反向重复序列之间的距离增加到25个碱基对就可以增加它们的染色体稳定性。切除的频率不受代表性rad突变的影响，但受影响DNA合成的某些基因突变的影响。特别是，编码DNA聚合酶I大亚基的基因POL1/CDC 17的突变显著增加了发夹缺失的频率，暗示该蛋白质参与了基因组TIR的正常表达。
Tandem inverted repeats (TIRs or hairpins) of 30 and 80 base-pair unit lengths are unstable mitotically in yeast (Saccharomyces cerevisiae). TIR instability results from deletions that remove part or all of the presumed hairpin structure from the chromosome. At least one deletion endpoint is always at or near the base of the hairpin, and almost all of the repaired junctions occur within short direct sequence repeats of 4 to 9 base pairs. The frequency of this event, which we call "hairpin excision," is influenced by chromosomal position, length of the inverted repeats, and the distance separating the repeat units; increasing the distance between the inverted repeats as little as 25 base pairs increases their chromosomal stability. The frequency of excision is not affected by representative rad mutations, but is influenced by mutations in certain genes affecting DNA synthesis. In particular, mutations in POL1/CDC17, the gene that encodes the large subunit of DNA polymerase I, increase the frequency of hairpin deletions significantly, implicating this protein in the normal maintainance of genomic TIRs.