Newt satellite 2 transcripts self-cleave by using an extended hammerhead structure.
AUTOR(ES)
Pabón-Peña, L M
RESUMO
Synthetic transcripts of satellite 2 DNA from newts undergo self-catalyzed, site-specific cleavage in vitro. Cleavage occurs within a domain that is similar to the hammerhead domain used by a number of self-cleaving, infectious plant RNAs. The newt hammerhead has a potentially unstable structure due to a stem composed of two base pairs and a 2-nucleotide loop, and unlike other hammerheads that have been studied, it cannot cleave as an isolated unit. Here we show that cleavage by a single newt hammerhead requires additional satellite 2 sequences flanking both ends of the hammerhead domain. We also present a structural model of a truncated satellite 2 transcript which is capable of cleavage. The structure includes an internally looped extension to one of the conserved stems of the hammerhead. By in vitro mutagenesis, the identities of each of the five nucleotides composing one of the internal loops were shown to be critical for cleavage. Additional evidence that the extension stimulates self-cleavage in a manner other than by simply stabilizing the hammerhead is presented.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=361788Documentos Relacionados
- Plus and minus RNAs of peach latent mosaic viroid self-cleave in vitro via hammerhead structures.
- Antigenomic Hepatitis delta virus ribozymes self-cleave in 18 M formamide.
- Alternative modes of self-cleavage by newt satellite 2 transcripts.
- The strands of both polarities of a small circular RNA from carnation self-cleave in vitro through alternative double- and single-hammerhead structures.
- RNA stem stability in the formation of a self-cleaving hammerhead structure.