Complete nucleotide sequence of chikungunya virus and evidence for an internal polyadenylation site
Autor(es): Khan Afjal Hossain, Morita Kouichi, Parquet Md Maria del Carmen, Hasebe Futoshi, Mathenge Edward G M, Igarashi Akira
Resumo: In this study, the complete genomic sequence of chikungunya virus (CHIK; S27 African prototype) was determined - the presence of an internal polyadenylation [I-poly(A)] site was confirmed within the 3' non-translated region (NTR) of this strain. The complete genome was 11805 nucleotides in length, excluding the 5' cap nucleotide, an I-poly(A) tract - the 3' poly(A) tail. It comprised two long open reading frames that encoded the non-structural (2474 amino acids) - structural polyproteins (1244 amino acids). The genetic location of the non-structural - structural proteins was predicted by comparing the deduced amino acid sequences with the known cleavage sites of other alphaviruses, located at the C-terminal region of their virus-encoded proteins. In addition, predicted secondary structures were identified within the 5' NTR - repeated sequence elements (RSEs) within the 3' NTR. Amino acid sequence homologies, phylogenetic analysis of non-structural - structural proteins - characteristic RSEs revealed that although CHIK is closely related to o'nyong-nyong virus, it is in fact a distinct virus. The existence of I-poly(A) fragments with different lengths (e.g. 19, 36, 43, 91, 94 - 106 adenine nucleotides) at identical initiation positions for each clone strongly suggests that the polymerase of the alphaviruses has a capacity to create poly(A) by a template-dependant mechanism such as 'polymerase slippage', as has been reported for vesicular stomatitis virus.
Imprenta: The Journal of General Virology, v. 83, Pt 12, p. 3075-3084, 2002
Identificador do objeto digital: 10.1099/0022-1317-83-12-3075
Descritores: Chikungunya virus - Biosynthesis ; Chikungunya virus - DNA ; Chikungunya virus - Genome ; Chikungunya virus - Molecular structure ; Chikungunya virus - Pathogenesis ; Chikungunya virus - Proteins ; Chikungunya virus - RNA ; Chikungunya Virus - Virus
Data de publicação: 2002
