- Tytuł:
- Viroids: unusual small pathogenic RNAs.
- Autorzy:
- Góra-Sochacka, Anna
- Powiązania:
- https://bibliotekanauki.pl/articles/1041535.pdf
- Data publikacji:
- 2004
- Wydawca:
- Polskie Towarzystwo Biochemiczne
- Tematy:
-
central conserved region
viroid
Avsunviroidae family
Pospiviroidae family
hammerhead ribozyme
rod-like structure - Opis:
- Viroids are small (about 300 nucleotides), single-stranded, circular, non-encapsidated pathogenic RNA molecules. They do not code for proteins and thus depend on plant host enzymes for their replication and other functions. They induce plant diseases by direct interaction with host factors but the mechanism of pathogenicity is still unknown. They can alter the expression of selected plant genes important for growth and development. Viroids belong to two families, the Avsunviroidae and the Pospiviroidae. Viroids of the Avsunviroidae family adopt a branched or quasi rod-like secondary structure in their native state. Members of the Pospiviroidae family adopt a rod-like secondary structure. In such native structures five structural/functional domains have been identified: central (C), pathogenicity, variable and two terminal domains. The central conserved region (CCR) within the C domain characterizes viroids of the Pospiviroidae. Specific secondary structures of this region play an important role in viroid replication and processing. Viroids of the Avsunviroidae family lack a CCR but possess self-cleaving properties by forming hammerhead ribozyme structures; they accumulate and replicate in chloroplasts, whereas members of the Pospiviroidae family have a nuclear localization. Viroid replication occurs via a rolling circle mechanism using either a symmetric or asymmetric pathway in three steps, RNA transcription, processing and ligation.
- Źródło:
-
Acta Biochimica Polonica; 2004, 51, 3; 587-607
0001-527X - Pojawia się w:
- Acta Biochimica Polonica
- Dostawca treści:
- Biblioteka Nauki