Full-length genome analyses of two new simian immunodeficiency virus (SIV) strains from mustached monkeys (C. Cephus) in Gabon illustrate a complex evolutionary history among the SIVmus/mon/gsn lineage.

Florian Liégeois,François Rouet,Eric Delaporte,Martine Peeters,Eric Leroy,Paul Ngari,Fatima Mouacha,Fabian Schmidt,Vanina Boué,Bertrand Ondo,Christelle Butel,Jonathan Heeney

doi:10.3390/v6072880

Abstract

The Simian Immunodeficiency Virus (SIV) mus/mon/gsn lineage is a descendant of one of the precursor viruses to the HIV-1/SIVcpz/gor viral lineage. SIVmus and SIVgsn were sequenced from mustached and greater spot nosed monkeys in Cameroon and SIVmon from mona monkeys in Cameroon and Nigeria. In order to further document the genetic diversity of SIVmus, we analyzed two full-length genomes of new strains identified in Gabon. The whole genomes obtained showed the expected reading frames for gag, pol, vif, vpr, tat, rev, env, nef, and also for a vpu gene. Analyses showed that the Gabonese SIVmus strains were closely related and formed a monophyletic clade within the SIVmus/mon/gsn lineage. Nonetheless, within this lineage, the position of both new SIVmus differed according to the gene analyzed. In pol and nef gene, phylogenetic topologies suggested different evolutions for each of the two new SIVmus strains whereas in the other nucleic fragments studied, their positions fluctuated between SIVmon, SIVmus-1, and SIVgsn. In addition, in C1 domain of env, we identified an insertion of seven amino acids characteristic for the SIVmus/mon/gsn and HIV‑1/SIVcpz/SIVgor lineages. Our results show a high genetic diversity of SIVmus in mustached monkeys and suggest cross-species transmission events and recombination within SIVmus/mon/gsn lineage. Additionally, in Central Africa, hunters continue to be exposed to these simian viruses, and this represents a potential threat to humans.

Highlights

IntroductionViruses (SIV) infecting apes from West Central Africa and sooty mangabeys from West Africa, respectively [1]
Human Immunodeficiency Viruses Type 1 and 2 (HIV-1 & -2) stem from Simian ImmunodeficiencyViruses (SIV) infecting apes from West Central Africa and sooty mangabeys from West Africa, respectively [1]
For this sample and two (Pts02, OIF02) of 46 additional DNA samples extracted from lymph nodes, an Simian Immunodeficiency Virus (SIV) pol PCR fragment (300 bp) was successfully amplified and compared to representative SIV lineages known to date (Figure S1)

Summary

Introduction

Viruses (SIV) infecting apes from West Central Africa and sooty mangabeys from West Africa, respectively [1]. Beyond these well-described SIVs, a plethora of non-human primates (NHPs) in sub-Saharan Africa are SIV carriers [2]. SIV, i.e., multiple strains from the same host species form a monophyletic clade. A single NHP species can be infected by two different. A divergent SIVmus strain was partially identified in mustached monkeys (C. cephus cephus) inhabiting Gabon [8]. Mustached monkeys were the first monkey species known to date to carry three different SIV lineages [8]

Methods

Results

Discussion

Conclusion