HIV-1 capsid stability enables inositol phosphate-independent infection of target cells and promotes integration into genes

The mature HIV-1 capsid is stabilized by host and viral determinants. The capsid protein CA binds to the cellular metabolites inositol hexakisphosphate (IP6) and its precursor inositol (1, 3, 4, 5, 6) pentakisphosphate (IP5) to stabilize the mature capsid. In target cells, capsid destabilization by the antiviral compounds lenacapavir and PF74 reveals an HIV-1 infectivity defect due to IP5/IP6 (IP5/6) depletion.  To test whether intrinsic HIV-1 capsid stability and/ or host factor binding determines HIV-1 insensitivity to IP5/6 depletion, a panel of CA mutants was assayed for infection of IP5/6-depleted T cells and wildtype cells.  Four CA mutants with unstable capsids exhibited dependence on host IP5/6 for infection and reverse transcription (RTN).  Adaptation of one such mutant, Q219A, by spread in culture resulted in Vpu truncation and a capsid three-fold interface mutation, T200I.  T200I increased intrinsic capsid stability as determined by in vitro uncoating of purified cores and pa..., , Please use Microsoft Excel or Open Office equivalent.  All other files can be opened with a text editor.