The Rad27 (Fen-1) nuclease inhibits Ty1 mobility in Saccharomyces cerevisiae.
The Rad27 (Fen-1) nuclease inhibits Ty1 mobility in Saccharomyces cerevisiae.
复制标题
Rad27 (Fen-1) 核酸酶抑制酿酒酵母中的 Ty1 迁移性。
DOI：
10.1093/genetics/163.1.55
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发表时间：
2003
期刊：
影响因子：
3.3
通讯作者：
Garfinkel,DavidJ
中科院分区：
文献类型：
--
作者：
Sundararajan,Anuradha;Lee,Bum-Soo;Garfinkel,DavidJ
虽然酵母菌中的大多数Ty1元件都能进行反转录转座，但宿主防御基因可以抑制Ty1生命周期的不同步骤。在这里，我们证明，Rad27，一种结构特异性核酸酶，在DNA复制和基因组稳定性中起着重要作用，抑制Ty1在翻译后水平。我们研究了不同rad27突变对Ty1元件反转录转座和cDNA重组的影响，称为Ty1迁移率。点突变rad 27-G67 S、rad 27-G240 D和rad 27-E158 D在体外引起某些酶活性的缺陷，导致Ty1迁移率的可变增加，范围从4到22倍。C-末端移码突变rad27 - 324赋予Ty1迁移率的最大增加（198倍）、未掺入的cDNA和在优选靶位点的插入。无效突变与其他27个等位基因的不同之处在于增加了多聚体Ty1插入和与基因组元件的cDNA重组的频率。Therad27突变体不显著改变Ty1 RNA或TyA1-gag蛋白的水平。然而，在rad27 - 324和无效突变体中，未掺入的Ty1 cDNA的稳定性增加。我们的研究结果表明，Rad27抑制Ty1流动性不稳定未纳入Ty1 cDNA和防止形成Ty1多聚体。
Although most Ty1 elements inSaccharomyces cerevisiaeare competent for retrotransposition, host defense genes can inhibit different steps of the Ty1 life cycle. Here, we demonstrate that Rad27, a structure-specific nuclease that plays an important role in DNA replication and genome stability, inhibits Ty1 at a posttranslational level. We have examined the effects of variousrad27mutations on Ty1 element retrotransposition and cDNA recombination, termed Ty1 mobility. The point mutationsrad27-G67S, rad27-G240D, andrad27-E158Dthat cause defects in certain enzymatic activitiesin vitroresult in variable increases in Ty1 mobility, ranging from 4- to 22-fold. The C-terminal frameshift mutationrad27-324confers the maximum increase in Ty1 mobility (198-fold), unincorporated cDNA, and insertion at preferred target sites. The null mutation differs from the otherrad27alleles by increasing the frequency of multimeric Ty1 insertions and cDNA recombination with a genomic element. Therad27mutants do not markedly alter the levels of Ty1 RNA or the TyA1-gag protein. However, there is an increase in the stability of unincorporated Ty1 cDNA inrad27-324and the null mutant. Our results suggest that Rad27 inhibits Ty1 mobility by destabilizing unincorporated Ty1 cDNA and preventing the formation of Ty1 multimers.