HIV-1 and the host cell: an intimate association

As obligate parasites, viruses must rely heavily on host cell machinery to replicate and spread. Because of their relatively limited coding capacity, viruses with small genomes are particularly dependent on cellular factors. In the case of retroviruses, interactions with host cell machinery are evident at virtually every step in the replication cycle, from binding and entry to particle release. Recent studies on human immunodeficiency virus type 1 (HIV-1) have illustrated the extent to which retroviruses have evolved to usurp host cell processes and counter intracellular antiviral defenses. This review highlights the relationship between HIV-1 and host factors, and focuses on new developments in our understanding of how HIV-1 has evolved to use cellular machinery and avoid antiviral restriction.