Two related glycoproteins (G and GNs ) encoded in the bovine ephemeral fever virus (BEFV) genome were expressed from recombinant vaccinia viruses (rVV). Both proteins were detected in lysates of rVV-infected cells by labelling with D-[6-3H]glucosamine or by immuno-blotting. The recombinant G protein (mol. mass 79 kDa) appeared slightly smaller than the native G protein but reacted with monoclonal antibodies directed against all defined neutralizing antigenic sites (G1, G2, G3a, G3b and G4). The recombinant G~s protein (mol. mass 90 kDa) was identical in size to the native GNs protein and failed to react by immunofluorescence with anti-G protein monoclonal or polyclonal antibodies. Antisera raised in rabbits against rVV-G or rVV-GNs both reacted strongly by immunofluorescence and immuno-electron microscopy with BEFV-infected cells. The G protein was localized intracellularly in the endoplasmic reticulum/Golgi complex and at the cell surface associated with budding and mature virus particles. The GNs protein also localized intracellularly in the endoplasmic reticulum/Golgi complex; however, at the cell surface it was associated with amorphous structures and not with budding or mature virions. Rabbits vaccinated with rVV-G developed high levels of antibodies which neutralized BEFV grown in either mammalian or insect cells. Cattle vaccinated with rVV-G also produced neutralizing antibodies and were protected against experimental BEFV infection. In contrast, rW-GNs vaccinated rabbits and cattle failed to produce neutralizing antibodies and, after challenge, BEFV was isolated from two-thirds of the vaccinated cattle.

The nucleotide sequences of the NS 1 genes from five Thai and three Sri Lankan dengue-2 viruses were determined by sequencing the viral RNA using synthetic oligonucleotide primers. The results were shown to be similar to four published dengue-2 NS 1 sequences and the classification of these genes was compared with the one obtained for the envelope genes of the same viruses. The classification was similar and showed that the Thai isolates could be divided into two separate groups and that the Sri Lankan isolates were distinct. We found no correlation between disease severity, serological response (1 degree or 2 degrees), or year of isolation and various aspects of NS 1 protein sequence variation; and no particular amino acid changes were correlated with virulence. The sequences were combined with those published and classified elsewhere to provide a comprehensive E/NS 1 gene taxonomy of dengue-2 virus isolates.

A comparison of the sequence of the dengue-2 16681 virus with that of the candidate vaccine strain (16681-PDK53) derived from it identified 53 of the 10,723 nucleotides which differed between the strains. Nucleotide changes occurred in genes coding for all virion and nonvirion proteins, and in the 5' and 3' untranslated regions. Twenty-seven of the nucleotide changes resulted in amino acid alterations. The greatest amino acid sequence differences in the virion proteins occurred in prM (2.20%; 2/91 amino acids) followed by the M protein (1.33%; 1/75 amino acids), the C protein (0.88%; 1/114 amino acid), and the E protein (0.61%; 3/495 amino acids). Differences in the amino acid sequence of nonvirion proteins ranged from 1.51% (6/398 amino acids) in NS4 to 0.33% (3/900 amino acids) in NS5. The encoded protein sequences of 16681-PDK53 were also compared with the published sequences of other flaviviruses to obtain a detailed classification of 17 flaviviruses using the neighbor-joining tree method. The analyses of the sequence data produced dendrograms which supported the traditional groupings based on serological evidence, and they suggested that the flaviviruses have evolved by divergent mutational change and there was no evidence of genetic recombination between members of the group. Comparisons of the sequences of the flavivirus polymerase and helicase-like proteins (NS5 and NS3, respectively) with those from other viruses yielded a classification of the flaviviruses indicating that the primary division of the flaviviruses was between those transmitted by mosquitoes and those transmitted by ticks.

The length of the post-partum anoestrous interval affects reproductive efficiency in many tropical beef cattle herds. In this study, results from genome-wide association studies (Experiment 1: GWAS) and gene expression (Experiment 2: microarray) were combined in a systems approach to reveal genetic markers, genes and pathways underlying the physiology of post-partum anoestrus in tropically adapted cattle. The microarray study measured the expression of 13,964 genes in the hypothalamus of Brahman cows. A total of 366 genes were differentially expressed (DE) in the post-partum period, when acyclic cows were compared to cows that had resumed ovarian cycles. Associated markers (P < 0.05) from a high density GWAS pointed to 2,829 genes that were associated with post-partum anoestrous interval we found genes with changed expression in the brain that were also associated with anoestrus traits these 63 genes could have biological significance in post-partum anoestrus in cows these genes could also help select cattle with genetic potential for shorter post-partum anoestrus