THE NON-ENV TROPISM OF HIV SIV (REVIEW)

The tropism of human and simian immunodeficiency viruses (HIV and SIV) determined by sequences other than env has been studied. The restrict ion of HIV-1 replication in monkey cells was demonstrated to be regula ted by viral non-env sequence. Likewise, the gag-pol region of SIVagm (virus of the African green monkey) genome was found to be responsible for growth restriction in human cells of the virus; No viral DNA synt hesis was detected in cells nonpermissive for the viruses. In addition , a number of HIV-1 gag gene mutants, which have an early defect in vi ral replication cycle and direct no viral DNA synthesis in some cells, exhibited a phenotype of host range mutant. Taken together, it can be concluded that the viral tropism associated with the uncoating/revers e transcription process does exist in HIV/SIV replication. Furthermore , many of the accessory gene mutants of HIV/SIV exhibit host cell-depe ndent replication property. In this review, we summarize these example s of non-env tropism of HIV/SIV.