Posttranscriptional gene silencing is not compromised in the Arabidopsis CARPEL FACTORY (DICER-LIKE1) mutant, a homolog of dicer-1 from Drosophila
Posttranscriptional gene silencing is not compromised in the Arabidopsis CARPEL FACTORY (DICER-LIKE1) mutant, a homolog of dicer-1 from Drosophila
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DOI：
10.1016/s0960-9822(03)00010-1
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发表时间：
2003-02-04
期刊：
影响因子：
9.2
通讯作者：
Waterhouse, PM
中科院分区：
文献类型：
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作者：
Finnegan, EJ;Margis, R;Waterhouse, PM
在植物、线虫、果蝇和可能所有的真核生物中的转录后沉默（PTGS）;通过靶mRNA的序列特异性降解或翻译抑制起作用。这些过程是由RNA介导的。在果蝇和线虫中，双链（ds）RNA或自身互补RNA被Dicer-1加工成约21 nt的片段[1，2]。这些小干扰RNA（siRNA）可作为同源单链（ss）RNA靶向降解的向导[1，3]。在某些情况下，源自内源性不完全自身互补RNA的约21 nt指导片段导致其靶mRNA的翻译抑制，它们与靶mRNA具有实质性但不完全的序列互补性[4-6]。这些小的时间RNA（stRNA）属于一类长度为20-24 nt的非编码microRNA（miRNA），其存在于文件、植物、线虫和哺乳动物中[4，6-12]。在线虫中，Dicer-1酶催化siRNA和stRNA的产生[2，13-15]。拟南芥Dicer-1同源物CARPEL FACTORY（CAF）的突变阻断了miRNA的产生[1，4，16 -18]。在这里，我们报告说，相同的caf突变体不会阻止自互补发夹RNA诱导的PTGS或siRNA的产生。这表明这种突变只会损害miRNA的形成，或者更有趣的是，植物有两种不同的dicer样酶，一种用于miRNA，另一种用于siRNAi的产生。
Posttranscriptional silencing (PTGS) in plants, nematodes, Drosophila, and perhaps all eukaryotes; operates by sequence-specific degradation or translational inhibition of the target mRNA. These processes are mediated by duplexed RNA. In Drosophila and nematodes, double-stranded (ds)RNA or self-complementary RNA is processed into fragments of approximately 21 nt by Dicer-1 [1, 2]. These small interfering RNAs (siRNAs) serve as guides to target degradation of homologous single-stranded (ss)RNA [1, 3]. In some cases, the approximately 21 nt guide fragments derived from endogenous, imperfectly self-complementary RNAs cause translational inhibition of their target mRNAs, with which they have substantial, but not perfect sequence complementarity [4-6]. These small temporal RNAs (stRNAs) belong to a class of noncoding microRNAs (miRNAs), 20-24 nt in length, that are found in files, plants, nematodes, and mammals [4, 6-12]. In nematodes, the Dicer-1 enzyme catalyzes the production of both siRNA and stRNA [2, 13-15]. Mutation of the Arabidopsis Dicer-1 homolog, CARPEL FACTORY (CAF), blocks miRNA production [1, 4,16-18]. Here, we report that the same caf mutant does not block either PTGS or siRNA production induced by self-complementary hairpin RNA. This suggests dither that this mutation only impairs miRNA formation or, more interestingly, that plants have two distinct dicer-like enzymes, one for miRNA and another for siRNAi production.