HIV suppression by host restriction factors and viral immune evasion

• Trim5α senses HIV capsid patterns and achieves strong binding by avidity.
• MxB binds to the HIV capsid assembly and may interfere with HIV nuclear import.
• HIV-1 Vif hijacks a host E3 ubiquitin ligase to antagonize APOBEC3 proteins.
• Allosteric GTP and dNTPs together activate the tetrameric SAMHD1 dNTPase.
• HIV-1 Vpu hijacks clathrin AP1 for the mistrafficking of BST2/tetherin.

Antiviral restriction factors are an integral part of the host innate immune system that protects cells from viral pathogens, such as human immunodeficiency virus (HIV). Studies of the interactions between restriction factors and HIV have greatly advanced our understanding of both the viral life cycle and basic cell biology, as well as provided new opportunities for therapeutic intervention of viral infection. Here we review the recent developments towards establishing the structural and biochemical bases of HIV inhibition by, and viral countermeasures of, the restriction factors TRIM5, MxB, APOBEC3, SAMHD1, and BST2/tetherin.