Link between primate lentiviral coreceptor usage and Nef function.

ABSTRACT: Simian immunodeficiency virus (SIVsmm) infection of sooty mangabeys (Cercocebus atys) is characterized by stable CD4(+) T cell counts despite high plasma levels of CCR5-tropic viruses. However, in rare instances, SIVsmm acquires CXCR4 coreceptor tropism and causes severe CD4(+) T cell depletion, albeit without clinical signs of immunodeficiency. Here, we show that CXCR4-tropic SIVsmm strains lost their ability to downmodulate TCR-CD3 by evolving unusual Nef mutations that initially reduced (I132V) and subsequently disrupted (I123L and L146F) interaction with the CD3 ζ chain. This coevolution of Env and Nef function suggests that CD3 downmodulation is advantageous for viral replication in activated CCR5(+) memory T cells, but not in resting naive CXCR4(+) T cells that have not yet undergone

SUBMITTER: Schmokel J 

PROVIDER: S-EPMC4133736 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature