Sequence and translation of the murine coronavirus 5'-end genomic RNA reveals the N-terminal structure of the putative RNA polymerase.
AUTOR(ES)
Soe, L H
RESUMO
A 28-kilodalton protein has been suggested to be the amino-terminal protein cleavage product of the putative coronavirus RNA polymerase (gene A) (M.R. Denison and S. Perlman, Virology 157:565-568, 1987). To elucidate the structure and mechanism of synthesis of this protein, the nucleotide sequence of the 5' 2.0 kilobases of the coronavirus mouse hepatitis virus strain JHM genome was determined. This sequence contains a single, long open reading frame and predicts a highly basic amino-terminal region. Cell-free translation of RNAs transcribed in vitro from DNAs containing gene A sequences in pT7 vectors yielded proteins initiated from the 5'-most optimal initiation codon at position 215 from the 5' end of the genome. The sequence preceding this initiation codon predicts the presence of a stable hairpin loop structure. The presence of an RNA secondary structure at the 5' end of the RNA genome is supported by the observation that gene A sequences were more efficiently translated in vitro when upstream noncoding sequences were removed. By comparing the translation products of virion genomic RNA and in vitro transcribed RNAs, we established that our clones encompassing the 5'-end mouse hepatitis virus genomic RNA encode the 28-kilodalton N-terminal cleavage product of the gene A protein. Possible cleavage sites for this protein are proposed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=256017Documentos Relacionados
- Requirement of the 5'-end genomic sequence as an upstream cis-acting element for coronavirus subgenomic mRNA transcription.
- trans-Complementation Analysis of the Flavivirus Kunjin ns5 Gene Reveals an Essential Role for Translation of Its N-Terminal Half in RNA Replication†
- NMR solution structure of a dsRNA binding domain from Drosophila staufen protein reveals homology to the N-terminal domain of ribosomal protein S5.
- NMR solution structure of a double-stranded RNA-binding domain from Drosophila staufen protein reveals homology to the N-terminal domain of ribosomal protein S5
- Crystal structure of the Sec18p N-terminal domain