Chen Z, Telfier P, Gettie A, Reed P, Zhang L, Ho D D, Marx P A
The Aaron Diamond AIDS Research Center, New York 10016, USA.
J Virol. 1996 Jun;70(6):3617-27. doi: 10.1128/JVI.70.6.3617-3627.1996.
It has been proposed that human immunodeficiency virus type 2 (HIV-2) originated from simian immunodeficiency viruses (SIVs) that are natural infections of sooty mangabeys (Cercocebus torquatus atys). To test this hypothesis, SIVs from eight sooty mangabeys, including six new viruses from West Africa, were genetically characterized. gag and env sequences showed that while the viruses of all eight sooty mangabeys belonged to the SIVsm/HIV-2 family, each was widely divergent from SIVs found earlier in captive monkeys at American primate centers. In two SIVs from sooty mangabeys discovered about 100 miles (ca. 161 Km) from each other in rural West Africa, the amino acids of a conserved gag p17-p26 region differed by 19.3%, a divergence greater than that in four of five clades of HIV-2 and in SIVs found in other African monkey species. Analysis of gag region sequences showed that feral mangabeys in one small troop harbored four distinct SIVs. Three of the newly found viruses were genetically divergent, showing as much genetic distance from each other as from the entire SIVsm/HIV-2 family. Sequencing and heteroduplex analysis of one feral animal-derived SIV showed a mosaic genome containing an env gene that was homologous with other feral SIVsm env genes in the troop but having a gag gene from another, distinct SIV. Surprisingly a gag phylogenetic tree based on nucleotide sequences showed that the African relatives closest to all three household-derived SIVs were HIV-2 subtypes D and E from humans in the same West African areas. In one case, the SIV/HIV-2 cluster was from the same village. The findings support the hypothesis that each HIV-2 subtype in West Africans originated from widely divergent SIVsm strains, transmitted by independent cross-species events in the same geographic locations.
有人提出，人类免疫缺陷病毒2型（HIV - 2）起源于自然感染乌黑白眉猴（Cercocebus torquatus atys）的猿猴免疫缺陷病毒（SIVs）。为了验证这一假说，对来自8只乌黑白眉猴的SIVs进行了基因特征分析，其中包括6种来自西非的新病毒。gag和env序列显示，虽然所有8只乌黑白眉猴的病毒都属于SIVsm/HIV - 2家族，但每一种都与此前在美国灵长类动物中心圈养猴子中发现的SIVs有很大差异。在西非农村地区彼此相距约100英里（约161公里）的两只乌黑白眉猴的SIVs中，保守的gag p17 - p26区域的氨基酸差异为19.3%，这种差异大于HIV - 2五个分支中的四个以及在其他非洲猴类物种中发现的SIVs。对gag区域序列的分析表明，一小群野生白眉猴体内携带四种不同的SIVs。新发现的三种病毒在基因上存在差异，彼此之间以及与整个SIVsm/HIV - 2家族的遗传距离都很大。对一种源自野生动物的SIV进行测序和异源双链分析显示，其基因组是嵌合的，包含一个与群体中其他野生SIVsm env基因同源的env基因，但gag基因来自另一种不同的SIV。令人惊讶的是，基于核苷酸序列的gag系统发育树显示，与所有三种源自圈养动物的SIVs亲缘关系最近的非洲亲属是来自同一西非地区人类的HIV - 2 D亚型和E亚型。在一个案例中，SIV/HIV - 2簇来自同一个村庄。这些发现支持了这样一种假说，即西非人的每种HIV - 2亚型都起源于广泛不同的SIVsm毒株，是在同一地理位置通过独立的跨物种传播事件传播而来的。
