Structured-Tree Topology and Adaptive Evolution of the Simian Immunodeficiency Virus SIVsm Envelope during Serial Passage in Rhesus Macaques According to Likelihood Mapping and Quartet Puzzling

AUTOR(ES)

Spencer Valli, P. J.

FONTE

American Society for Microbiology

RESUMO

Species-specific strains of simian immunodeficiency virus (SIV) are nonpathogenic in African primates. The SIV strain most closely related to human immunodeficiency virus type 2 (HIV-2) is SIVsm, the strain specific to the sooty mangabey (Cercocebus atys). Infection of Asian primates with SIV causes AIDS and allows the study of the adaptive evolution of a lentivirus to replicate efficiently in a new host, providing a useful animal model of HIV infection and AIDS in humans. Serial passage of SIVsm from sooty mangabeys in rhesus macaques drastically shortened the time of disease progression from 1.5 years to 1 month as the retrovirus adapted to these Asian hosts. In the present study we analyzed the quasispecies nature of the SIVsm envelope gene (env) during serial population passage in rhesus macaques. We asked ourselves if phylogenetic evidence could be provided for the structured topology of the SIVsm env tree and subsequently for the adaptive evolution of SIVsm env. Likelihood mapping showed that phylogenetic reconstruction of the passage was possible because a high percentage of the sequence data had a “tree-like” form. Subsequently, quartet puzzling was used and produced a phylogeny with a structure parallel to the known infection history. The adaptation of SIVsm to Asian rhesus macaques appears to be an ordered process in which the env evolves in a tree-like manner, particularly in its constant regions.

Documentos Relacionados

• Shortening of the Symptom-Free Period in Rhesus Macaques Is Associated with Decreasing Nonsynonymous Variation in the env Variable Regions of Simian Immunodeficiency Virus SIVsm during Passage
• Alterations in potential sites for glycosylation predominate during evolution of the simian immunodeficiency virus envelope gene in macaques.
• Evolution of the human immunodeficiency virus type 2 envelope gene in preimmunized and persistently infected rhesus macaques.
• Experimental Coinfection of Rhesus Macaques with Rhesus Cytomegalovirus and Simian Immunodeficiency Virus: Pathogenesis
• Reassortment of Simian Virus 40 DNA During Serial Undiluted Passage