Silencing of retrotransposons in Dictyostelium by DNA methylation and RNAi.
Silencing of retrotransposons in Dictyostelium by DNA methylation and RNAi.
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DOI：
10.1093/nar/gki952
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发表时间：
2005
影响因子：
14.9
通讯作者：
Nellen W
中科院分区：
文献类型：
--
作者：
Kuhlmann M;Borisova BE;Kaller M;Larsson P;Stach D;Na J;Eichinger L;Lyko F;Ambros V;Söderbom F;Hammann C;Nellen W
我们已经确定了Dnmt 2家族的DNA甲基转移酶在DnmA命名的网骨藻。dnmA基因的表达在发育周期中下调。在网骨藻中，总的DNA甲基化是胞嘧啶残基的约0.2%，这表明其局限于有限的一组基因组位点。亚硫酸氢盐测序的特定位点显示，DnmA是负责的逆转录转座子DIRS-1和Skipper中的大多数不对称的C-残基的甲基化。该基因的破坏导致甲基化的丧失和Skipper的转录和动员增加。Skipper转录也在RNA干扰途径的编码基因被破坏的菌株中上调。与此相反，DIRS-1的表达不受DnmA的损失，但强烈增加的菌株，有RNA指导的RNA聚合酶基因rrpC破坏。大量的siRNA被发现对应于DIRS-1序列，这表明通过RNAi和DNA修饰协同调节DIRS-1表达。没有发现与标准Skipper元件相对应的siRNA。数据表明，DNA甲基化在网柄藻的表观遗传基因沉默中起着至关重要的作用，但不同的，部分重叠的机制控制转座子沉默。
We have identified a DNA methyltransferase of the Dnmt2 family in Dictyostelium that was denominated DnmA. Expression of the dnmA gene is downregulated during the developmental cycle. Overall DNA methylation in Dictyostelium is ∼0.2% of the cytosine residues, which indicates its restriction to a limited set of genomic loci. Bisulfite sequencing of specific sites revealed that DnmA is responsible for methylation of mostly asymmetric C-residues in the retrotransposons DIRS-1 and Skipper. Disruption of the gene resulted in a loss of methylation and in increased transcription and mobilization of Skipper. Skipper transcription was also upregulated in strains that had genes encoding components of the RNA interference pathway disrupted. In contrast, DIRS-1 expression was not affected by a loss of DnmA but was strongly increased in strains that had the RNA-directed RNA polymerase gene rrpC disrupted. A large number of siRNAs were found that corresponded to the DIRS-1 sequence, suggesting concerted regulation of DIRS-1 expression by RNAi and DNA modification. No siRNAs corresponding to the standard Skipper element were found. The data show that DNA methylation plays a crucial role in epigenetic gene silencing in Dictyostelium but that different, partially overlapping mechanisms control transposon silencing.
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影响因子：
64.8
作者：
GRUENBAUM, Y;CEDAR, H;RAZIN, A
通讯作者：
RAZIN, A
影响因子：
14.9
作者：
HOWARD, PK;AHERN, KG;FIRTEL, RA
通讯作者：
FIRTEL, RA
影响因子：
1.6
作者：
Marhold, J;Zbylut, M;Lyko, F
通讯作者：
Lyko, F
影响因子：
30.8
作者：
Kanno, T;Huettel, B;Matzke, AJM
通讯作者：
Matzke, AJM
影响因子：
5.3
作者：
CAPPELLO, J;ZUKER, C;LODISH, HF
通讯作者：
LODISH, HF