Two chloroplastic viroids induce the accumulation of small RNAs associated with posttranscriptional gene silencing.
نویسندگان
چکیده
In plants, posttranscriptional gene silencing (PTGS) has been reported for cytoplasmic RNAs from endogenous nuclear genes, transgenes, viruses, and, recently, for a viroid with nuclear replication and accumulation. However, phenomena of this kind have not been described for mitochondrial or chloroplastic RNAs. Here we show that viroids that replicate and accumulate in the chloroplast are also targets of PTGS and this process may control viroid titer.
منابع مشابه
ogenicity, viroid evolution, Citrus exocortis viroid, Potato spindle tuber viroid, Peach latent mosaic viroid, Chrysan- themum chlorotic mottle viroid
Viroids are autonomously replicating, small singlestranded circular RNA molecules that do not code for proteins and may cause disease in infected, susceptible plants. Viroids have the ability to induce both RNA-mediated transcriptional gene silencing (TGS) and posttranscriptional gene silencing (PTGS) in infected plants. Viroid PTGS has also been demonstrated in a wheat germ extract system. A p...
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ورودعنوان ژورنال:
- Journal of virology
دوره 76 24 شماره
صفحات -
تاریخ انتشار 2002