Evolution of the primate lentiviruses: evidence from vpx and vpr.

AUTOR(ES)

Tristem, M

RESUMO

The genomes of the four primate lentiviral groups are complex and contain several regulatory or accessory genes. Two of these genes, vpr and vpx, are found in various combinations within the four groups and encode proteins whose functions have yet to be elucidated. Comparison of the encoded protein sequences suggests that the vpx gene within the HIV-2 group arose by the duplication of an ancestral vpr gene within this group. Evolutionary distance analysis showed that both genes were well conserved when compared with viral regulatory genes, and indicated that the duplication occurred at approximately the same time as the HIV-2 group and the other primate lentivirus groups diverged from a common ancestor. Furthermore, although the SIVagm vpx proteins are homologous to the HIV-2 group vpx proteins, there are insufficient grounds from sequence analysis for classifying them as vpx proteins. Because of their similarity to the vpr proteins of other groups, we suggest reclassifying the SIVagm vpx gene as a vpr gene. This creates a simpler and more uniform picture of the genomic organization of the primate lentiviruses and allows the genomic organization of their common precursor to be defined; it probably contained five accessory genes: tat, rev, vif, nef and vpr.

Documentos Relacionados

• Interaction with the p6 Domain of the Gag Precursor Mediates Incorporation into Virions of Vpr and Vpx Proteins from Primate Lentiviruses
• Vpr-induced cell cycle arrest is conserved among primate lentiviruses.
• Controlling lentiviruses: Single amino acid changes can determine specificity
• Slow, persistent replication of lentiviruses: role of tissue macrophages and macrophage precursors in bone marrow.
• Progression to AIDS in the absence of a gene for vpr or vpx.