Evidence for cell surface association between CXCR4 and ganglioside GM3 after gp120 binding in SupT1 lymphoblastoid cells.
CXCR4 (fusin) is a chemokine receptor which is involved as a coreceptor in gp120 binding to the cell surface. In this study we provide evidence that binding of gp120 triggers CXCR4 recruitment to glycosphingolipid-enriched microdomains. Scanning confocal microscopy showed a nearly complete localization of CXCR4 within GM3-enriched plasma membrane domains of SupT1 cells and coimmunoprecipitation experiments revealed that CXCR4 was immunoprecipitated by IgG anti-GM3 after gp120 pretreatment. These findings reveal that gp120 binding induces a strict association between CXCR4 and ganglioside GM3, supporting the view that GM3 and CXCR4 are components of a functional multimolecular complex critical for HIV-1 entry.
Sorice
M
M
Dipartimento di Medicina Sperimentale e Patologia, Università de Roma La Sapienza, Italy.
Garofalo
T
T
Misasi
R
R
Longo
A
A
Mattei
V
V
Sale
P
P
Dolo
V
V
Gradini
R
R
Pavan
A
A
D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002855:Chromatography, Thin Layer; D005679:G(M3) Ganglioside / Q000378:metabolism*; D015699:HIV Envelope Protein gp120 / Q000378:metabolism; D006801:Humans; D011233:Precipitin Tests; D011485:Protein Binding; D019718:Receptors, CXCR4 / Q000378:metabolism*
D005679:G(M3) Ganglioside; D015699:HIV Envelope Protein gp120; D019718:Receptors, CXCR4