Human immunodeficiency virus type 1 envelope glycoprotein 120 C5 domain (HIV-1 gp120 C5)

The HIV-1 gp120 C5 domain is the fifth conserved, C-terminal region of the surface envelope glycoprotein gp120. It plays a vital structural role by mediating the non-covalent interaction between gp120 and the transmembrane subunit gp41, which is essential for maintaining the stability of the functional envelope trimer on the viral surface. During the infection process, gp120 facilitates viral attachment to host CD4 receptors and co-receptors, while the C5 domain ensures the integrity of the envelope complex required for subsequent gp41-mediated membrane fusion. In therapeutic research, the C5 domain is a significant target for vaccine development and monoclonal antibody therapy, as antibodies directed against this region can interfere with the gp120-gp41 interface or mediate antibody-dependent cellular cytotoxicity (ADCC). However, the domain is often occluded within the native pre-fusion trimer, presenting a challenge for the development of broadly neutralizing antibodies.

Other names

gp120 C5 regionC5 domain of gp120HIV-1 gp120 C-terminusEnvelope glycoprotein gp120 constant domain 5

Inhibition of gp120-gp41 association, induction of antibody-dependent cellular cytotoxicity (ADCC), and viral neutralization through interference with envelope stability.