The HIV-TSG101 interface: recent advances in a budding field.

Efficient budding of HIV from the plasma membrane requires a small peptide motif, Pro-Thr/Ser-Ala-Pro (PTAP), located near the amino terminus of the p6 Gag protein. Studies from several laboratories have demonstrated that the ability of p6 to stimulate HIV budding requires a direct interaction between the PTAP motif and the host endosomal sorting protein TSG101. The structure of the PTAP-TSG101 binding site has recently been solved, providing valuable insights into this crucial protein-protein interaction.