Summary
The HIV-1 envelope glycoprotein (Env), a homotrimer of gp120-gp41 heterodimers, mediates viral entry into host cells. The gp120 subunit engages host receptors, while the gp41 subunit contains a fusion peptide (FP) that is inserted into the host membrane to induce host and virus membrane fusion. Prior to its binding to host receptors, the HIV-1 Env is characterized by a closed configuration with gp120 protomers packed against each other and the gp41 subunit, while the highly conserved and immunodominant coreceptor-binding region at the Env trimer apex remains occluded by packing of the first an
