Characterization of genotype II Rubella virus strains

Abstract

Two genotypes of Rubella virus have been described that differ by 8-9% at the nucleotide level in the E1 glycoprotein gene. Of these, genotype II (RGII) was only recently reported and in this study two RGII viruses, the BRDII vaccine strain and BR1 wild type strain, were characterized. Monoclonal antibodies against each of the virion proteins (capsid [C], glycoproteins E1 and E2) and polyclonal anti-rubella virus sera reacted similarly with purified virions from the RGII and reference RGI strains on Western gels, with the exception of one anti-E2 Mab, and thus the two genotypes are closely related antigenically. The genomic sequences of two genotype II (RGII) rubella virus strains were determined and compared with the six previously reported RGI sequences. The genomes of these viruses all contained 9762 nts and the lengths of the three untranslated regions (UTRs) and two open reading frames (ORF's) were identical. The overall difference between the RGI and RGII sequences at the nt level was approximately 8% and this difference was maintained across most of the genome. At the amino acid level, the RGI and RGII sequences differed overall by approximately 4%, however this difference was not uniform across the ORF's as the N-terminal third of P150 and the entirety of P90, both replicase proteins, were more conserved (<1% difference) while the C-terminal two thirds of P150 exhibited greater variation ( approximately 8% difference), including a hypervariable region between residues 771-801 within which divergence as great as 20-30% was detected. The parent wt virus of the BRDII vaccine was not available and its sequence was compared with the BR1 sequence to identify potential attenuating mutations. The BRDII and BR1 sequences varied at 252 residues (2.59%), including twelve in the UTRs and thirty coding differences in the ORF's. None of these differences in the BRDII sequence was vaccine-specific when compared with RGI wt and vaccine sequences and, therefore, there appeared to be no common pathway in the generation of live, attenuated rubella vaccines.

Phylogenetic Analysis of Envelope Glycoprotein (E1) Gene of Rubella Viruses Prevalent in Japan in 2004

“…Several molecular epidemiologic studies of the RV, including homology analysis of nucleotide and deduced amino acid sequences and phylogenetic analysis based on nucleotide sequences of partial E1 gene, have been reported (4,5,7,(19)(20)(21). The E1 protein is a major antigen of the RV (3, 15).…”

Molecular epidemiology of African swine fever in East Africa

“…Genome regions that are variable to hyper variable have proven useful in the endeavors of scientists to determine close relationships or further resolve within genotype or serotype relationships (Bornkamm et al, 1980;Sidagis et al, 1997;Duffy et al, 2002;Gao et al, 2003;Gonz′alez-Candelas et al, 2003;Zheng et al, 2003). A considerable number of these regions are sequence repeats, usually in the form of long terminal repeats (LTR) (Rohn et al, 1998;Chen et al, 1999;Yamashita et al, 1999) or short tandem repeats (STR) (Foster and Trimarchi, 1994;Rosenberg et al, 1994;Tautz and Schlotterer, 1994;Wills 1996, 1998 Duke et al, 1990;Garcia -Barreno et al, 1994;Yamada et al, 1996;Barr et al, 1997;Perdue et al, 1997).…”

Structural Basis of Severe Acute Respiratory Syndrome Coronavirus ADP-Ribose-1″-Phosphate Dephosphorylation by a Conserved Domain of nsP3

“…Orthologs of SARS ADRP are found embedded in nonstructural proteins of many related ssRNA viruses, especially in alphaviruses of togaviridae (group II of Figure 1B). These include, among others, nsP2 of Sindbis virus (Strauss et al, 1984), nsP3 of O'nyong-nyong virus (Lanciotti et al, 1998), nsP3 of Ross River virus (Shirako and Yamaguchi, 2000), P150 of the lone nsP in Rubella virus (Zheng et al, 2003), nsP3 of Mayaro virus (Anderson et al, 1954), and nsP3 of Semliki Forest virus (Tuittila et al, 2000). Many of these viruses have a greatly reduced genome size (w10 kb), with only about 4-5 ORFs.…”