RNA interference and receptors

@article{nisole_anti-hiv_1999,

title = {The anti-HIV pseudopeptide HB-19 forms a complex with the cell-surface-expressed nucleolin independent of heparan sulfate proteoglycans},

author = {S Nisole and B Krust and C Callebaut and G Guichard and S Muller and J P Briand and A G Hovanessian},

doi = {10.1074/jbc.274.39.27875},

issn = {0021-9258},

year  = {1999},

date = {1999-09-01},

journal = {The Journal of Biological Chemistry},

volume = {274},

number = {39},

pages = {27875--27884},

abstract = {The HB-19 pseudopeptide 5[Kpsi(CH(2)N)PR]-TASP, psi(CH(2)N) for reduced peptide bond, is a specific inhibitor of human immunodeficiency virus (HIV) infection in different CD4(+) cell lines and in primary T-lymphocytes and macrophages. Here, by using an experimental CD4(+) cell model to monitor HIV entry and infection, we demonstrate that HB-19 binds the cell surface and inhibits attachment of HIV particles to permissive cells. At concentrations that inhibit HIV attachment, HB-19 binds cells irreversibly, becomes complexed with the cell-surface-expressed nucleolin, and eventually results in its degradation. Accordingly, by confocal immunofluorescence microscopy, we demonstrate the drastic reduction of the cell-surface-expressed nucleolin following treatment of cells with HB-19. HIV particles can prevent the binding of HB-19 to cells and inhibit complex formation with nucleolin. Such a competition between viral particles and HB-19 is consistent with the implication of nucleolin in the process of HIV attachment to target cells. We show that another inhibitor of HIV infection, the fibroblast growth factor-2 (FGF-2) that uses cell-surface-expressed heparan sulfate proteoglycans as low affinity receptors, binds cells and blocks attachment of HIV to permissive cells. FGF-2 does not prevent the binding of HB-19 to cells and to nucleolin, and similarly HB-19 has no apparent effect on the binding of FGF-2 to the cell surface. The lack of competition between these two anti-HIV agents rules out the potential involvement of heparan sulfate proteoglycans in the mechanism of anti-HIV effect of HB-19, thus pointing out that nucleolin is its main target.},

keywords = {Anti-HIV Agents, Binding Sites, CD4-Positive T-Lymphocytes, Cell Line, Cell Membrane, Confocal, Fibroblast Growth Factor 2, Flow Cytometry, Heparan Sulfate Proteoglycans, HIV-1, Humans, Microscopy, Oligopeptides, Peptides, Phospholipid Ethers, Phosphoproteins, Proteins, RNA-Binding Proteins},

pubstate = {published},

tppubtype = {article}

}