Evolutionary rate shifts suggest species-specific adaptation events in HIV-1 and SIV

Maoz Gelbart; Adi Stern

Anti Tetherin/BST-2 adaptations. Tetherin/BST-2 is a trans-membrane antiviral 132 restriction factor that disrupts the budding phase of the retroviral lifecycle, thus preventing the 133 infection from spreading [26, 27] . SIVcpz and many more SIV's antagonize Tetherin through 134 interactions of their nef protein with the cytoplasmic tail of Tetherin [28, 29] . Tetherin is a fast 135 evolving protein, and differs between chimpanzee, gorilla and human [30, 31] . In humans, a 136 significant deletion in the cytoplasmic tail of Tetherin rendered it invulnerable to the SIV's Nef-137 based counteraction [29] . Therefore, in order to regain infectivity HIV-1 developed an 138 . CC-BY-NC-ND 4.0 International license is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. It . https://doi.org/10.1101/190769 doi: bioRxiv preprint alternative way to antagonize Tetherin. In groups M and N, Vpu protein adapted to antagonize 139