Replicating Potato spindle tuber viroid mediates de novo methylation of an intronic viroid sequence but no cleavage of the corresponding pre-mRNA
Replicating Potato spindle tuber viroid mediates de novo methylation of an intronic viroid sequence but no cleavage of the corresponding pre-mRNA
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DOI：
10.1080/15476286.2015.1017216
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发表时间：
2015-03-01
期刊：
影响因子：
4.1
通讯作者：
Wassenegger, Michael
中科院分区：
文献类型：
--
作者：
Dalakouras, Athanasios;Dadami, Elena;Wassenegger, Michael
在植物中，马铃薯纺锤块茎类病毒（PSTVd）复制分别触发同源RNA和DNA序列的转录后基因沉默（PTGS）和RNA指导的DNA甲基化（RdDM）。PTGS主要发生在细胞质中，但也有核PTGS的报道。在这项研究中，我们研究了核复制PSTVd是否能够触发核PTGS。携带细胞质和核PTGS传感器构建体的转基因烟草植物被PSTVd感染，导致产生丰富的PSTVd衍生的小干扰RNA（vd-siRNA）。北方印迹分析显示，与细胞质传感器相反，核传感器转录物不靶向RNA降解。亚硫酸氢盐测序分析表明，核PTGS传感器转基因是有效地针对RdDM。我们的数据表明，PSTVd未能触发核PTGS，RdDM和核PTGS不一定耦合。
In plants, Potato spindle tuber viroid (PSTVd) replication triggers post-transcriptional gene silencing (PTGS) and RNA-directed DNA methylation (RdDM) of homologous RNA and DNA sequences, respectively. PTGS predominantly occurs in the cytoplasm, but nuclear PTGS has been also reported. In this study, we investigated whether the nuclear replicating PSTVd is able to trigger nuclear PTGS. Transgenic tobacco plants carrying cytoplasmic and nuclear PTGS sensor constructs were PSTVd-infected resulting in the generation of abundant PSTVd-derived small interfering RNAs (vd-siRNAs). Northern blot analysis revealed that, in contrast to the cytoplasmic sensor, the nuclear sensor transcript was not targeted for RNA degradation. Bisulfite sequencing analysis showed that the nuclear PTGS sensor transgene was efficiently targeted for RdDM. Our data suggest that PSTVd fails to trigger nuclear PTGS, and that RdDM and nuclear PTGS are not necessarily coupled.