Figure 1

Hypothetical model of the HTLV receptor complex and HTLV entry: 1- HSPG interaction with the SU allow the initial attachment and concentration of the virions at the cell surface. 2- HSPG facilitates the recruitment of the SU to NRP-1. 3- Using molecular mimicry of VEGFA₁₆₅, the SU region 90-94 interacts with the b domain of NRP-1, an interaction that is stabilized by HSPG. 4- SU-NRP-1 interaction triggers a conformational change within the SU, allowing exposure of the tyrosine 114 that is critical for binding to GLUT1. Interaction between GLUT1 and the SU triggers a conformational change allowing the unmasking of the TM fusion peptide (not depicted). The small adaptor protein GLUT1CBP might form a link between NRP1 and GLUT1 and stabilize the receptor complex.