RNAi related mechanisms affect both transcriptional and posttranscriptional transgene silencing in Drosophila
RNAi related mechanisms affect both transcriptional and posttranscriptional transgene silencing in Drosophila
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DOI：
10.1016/s1097-2765(02)00440-9
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发表时间：
2002-02-01
期刊：
影响因子：
16
通讯作者：
Birchler, JA
中科院分区：
文献类型：
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作者：
Pal-Bhadra, M;Bhadra, U;Birchler, JA
在乙醇脱氢酶（Adh）转录单元上发现了两种类型的转基因沉默。转录基因沉默（TGS）是Polycomb依赖的，当Adh由白色眼睛颜色基因启动子驱动时发生。全长Adh转基因在高拷贝数或超过阈值的脉冲增加时转录后沉默。转录后基因沉默（PTGS）表现出RNA干扰（RNAi）的典型分子特征，包括产生与被沉默RNA同源的21- 25bp长度的正义RNA和反义RNA。piwi属于RNAi所需成员的基因家族，其突变可阻断PTGS和TGS的一个方面，表明两种沉默类型之间存在联系。
Two types of transgene silencing were found for the Alcohol dehydrogenase (Adh) transcription unit. Transcriptional gene silencing (TGS) is Polycomb dependent and occurs when Adh is driven by the white eye color gene promoter. Full-length Adh transgenes are silenced posttranscriptionally at high copy number or by a pulsed increase over a threshold. The posttranscriptional gene silencing (PTGS) exhibits molecular hallmarks typical of RNA interference (RNAi), including the production of 21-25 bp length sense and antisense RNAs homologous to the silenced RNA. Mutations in piwi, which belongs to a gene family with members required for RNAi, block PTGS and one aspect of TGS, indicating a connection between the two types of silencing.