5' termini of Pichinde arenavirus S RNAs and mRNAs contain nontemplated nucleotides.

AUTOR(ES)

Polyak, S J

RESUMO

Primer extension of Pichinde arenavirus purified virion RNA suggests that genomes have at least a single nontemplated base at the 5' end which is a G in all cDNA clones having one such single base. On the other hand, the predominant products of primer extension on total virus-infected-cell RNA are at positions -1 and -2. The primer extension product at position -2 is not represented in virion RNA, and neither of these products is proportionally represented in mRNA. mRNA is predominantly 3 or 4 bases longer than genomes and antigenomes, but primer extension products as long as 7 bases were observed. The sequence of nontemplated bases reported here is unambiguous with respect to the 5'-terminal base and supports the view that there is a sequence preference for a G at the 5' termini of mRNAs. Assessment of our sequence data in the context of the sequences of Tacaribe and lymphocytic choriomeningitis viruses suggests that the mechanism of initiation of arenavirus transcription is fundamentally different from that of members of the families Orthomyxoviridae and Bunyaviridae.

Documentos Relacionados

• Concurrent sequence analysis of 5' and 3' RNA termini by intramolecular circularization reveals 5' nontemplated bases and 3' terminal heterogeneity for lymphocytic choriomeningitis virus mRNAs.
• Sequence heterogeneity at the 5' termini of late simian virus 40 19S and 16S mRNAs.
• A highly sensitive method for mapping the 5' termini of mRNAs.
• Nucleotide sequences of the 5′ termini of φX174 mRNAs synthesized in vitro
• mRNAs that mature through trans-splicing in Caenorhabditis elegans have a trimethylguanosine cap at their 5' termini.