RESUMO
Bovine gammaherpesvirus 4 (BoGHV4) is a member of the Gammaherspivirinae subfamily, Rhadinovirus genus. Its natural host is the bovine, and it is prevalent among the global cattle population. Although the complete genome of BoGHV4 has been successfully sequenced, the functions of most of its genes remain unknown. Currently, only six strains of BoGHV4, all belonging to Genotype 1, have been sequenced. This is the first report of the nearly complete genome of Argentinean BoGHV4 strains isolated from clinical cases of abortion, representing the first BoGHV4 Genotype 2 and 3 genomes described in the literature. Both Argentinean isolates presented the highest nt p-distance values, indicating a greater level of divergence. Overall, the considerable diversity observed in the complete genomes and open reading frames underscores the distinctiveness of both Argentinean isolates compared to the existing BoGHV4 genomes. These findings support previous studies that categorized the Argentinean BoGHV4 strains 07-435 and 10-154 as Genotypes 3 and 2, respectively. The inclusion of these sequences represents a significant expansion to the currently limited pool of BoGHV4 genomes while providing an important basis to increase the knowledge of local isolates.
Assuntos
Aborto Animal , Doenças dos Bovinos , Genoma Viral , Infecções por Herpesviridae , Herpesvirus Bovino 4 , Sequenciamento Completo do Genoma , Animais , Bovinos , Feminino , Gravidez , Aborto Animal/virologia , Argentina , Doenças dos Bovinos/virologia , DNA Viral/genética , Variação Genética , Genótipo , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Herpesvirus Bovino 4/genética , Herpesvirus Bovino 4/isolamento & purificação , Fases de Leitura Aberta , FilogeniaRESUMO
Some viruses encode inhibitory factors of apoptosis during infection to prolong cell viability and then to achieve a higher production of viral progeny or facilitate persistent infections. There is evidence that some gammaherpesviruses, including BoHV-4, carry genes that can both inhibit or induce apoptosis. BoHV-4 possesses two genes (ORF16 and ORF71) that code for proteins with anti-apoptotic functions, such as v-Bcl2 and v-Flip, respectively. Thus, it is relevant to study BoHV-4 in relation to the modulation of apoptosis in infected cells as a strategy for persistence in the host. The objective of this work was to analyze whether variations in v-Flip and v- Bcl2 of six phylogenetically divergent Argentinean isolates of BoHV-4 can influence the capacity of these strains to induce apoptosis in cell cultures. In this study, variations were mainly detected in the v-Flip gene and protein of the BoHV-4 strains belonging to genotype 3. Thus, it is possible to infer that sequence variations could be associated with some BoHV-4 genotype. Induction of apoptosis was not a significant event for any of the genetically distinct local isolates of BoHV-4 and there was not an evident relationship between the variability of both genes with the apoptotic effect of the phylogenetically distinct strains.
Assuntos
Apoptose/genética , Herpesvirus Bovino 4/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Argentina , Sequência de Bases , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Bovinos , Doenças dos Bovinos/virologia , Linhagem Celular Tumoral , Genótipo , Células HeLa , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 4/isolamento & purificação , Humanos , Alinhamento de SequênciaRESUMO
Bovine herpevsirus 4 (BoHV-4) is a gammaherpesvirus that has been associated with different clinical conditions in cattle. In Argentina, BoHV-4 was detected in diverse bovine samples. The aim of this study was to analyze the genetic relationship of 48 field BoHV-4 strains isolated from cattle in Argentina. According to thymidine kinase (tk) gene sequences, BoHV-4 isolates belong to genotypes 1, 2 and 3. Phylogenetic analyses confirmed the presence of the three previously described viral genotypes. However, some of the studied isolates presented conflicting phylogenetic signals between the studied markers. This suggests a complex evolutionary background, that is a history of recombination, incomplete lineage sorting (deep coalescence) or a combination of these, which requires further study. These potential events make difficult the diagnosis of BoHV-4 from clinical samples of cattle and may pose a significant problem for the control of the virus in the herds.