Human T-lymphotropic virus type 1 envelope glycoprotein gp46[1][2][7] (gp46[1][2][7])

The Human T-lymphotropic virus type 1 envelope glycoprotein gp46, also known as the surface unit (SU) of the HTLV-1 Env protein, is a key viral glycoprotein responsible for mediating virus attachment to host cells during infection. It binds to heparan sulfate proteoglycans (HSPGs) on target cells such as T cells and dendritic cells, enhancing viral entry, and cooperates with neuropilin-1 (NRP-1) via a conserved KPxR motif that mimics vascular endothelial growth factor (VEGF165) binding.[1][2][5][7] This interaction triggers conformational changes in the transmembrane subunit gp21, facilitating membrane fusion and viral internalization, often in a cell-to-cell transmission manner characteristic of HTLV-1.[2][5] HTLV-1 gp46 is highly conserved among primate T-lymphotropic viruses and plays a central role in the virus's tropism for CD4+ T lymphocytes, contributing to persistent infection.[2][5] In disease contexts, it drives oncogenesis in adult T-cell leukemia/lymphoma (ATLL) and neurological damage in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) by enabling viral spread and immune evasion.[5][6] The protein elicits a strong humoral immune response, with antibodies targeting gp46 used in serological diagnostics like ELISA.[6][8] Although not a host therapeutic target, its receptor interactions suggest potential for antiviral strategies blocking HSPG or NRP-1 engagement, such as polyanions like dextran sulfate.[1][5]

Other names

HTLV-1 surface envelope glycoprotein SUHTLV-1 Env SU[2][5][7]