The C domain of HIV-1 gp41 binds the putative cellular receptor protein P62.
OBJECTIVE
To characterize the binding of gp41 with the putative receptor protein P62.


METHODS
HIV-1 gp41 binds several cellular proteins by two binding sites, one of which has been shown to bind to a putative receptor protein P45 (45 kDa). Based on this, an attempt was made to determine the relationship between the two binding sites and P62 (62 kDa).


METHODS
Using surface plasmon resonance (SPR) measurement, the interaction was measured between recombinant soluble gp41 (rsgp41, Env aa539-684) and protein P62. Inhibition of this interaction was attempted by the use of synthetic peptides (P1, aa583-599; P2, aa646-674) corresponding to the two binding sites in gp41. In addition, the direct binding of P62 to peptide P2 was examined in an enzyme-linked immunosorbent assay.


RESULTS
Using SPR measurement, the interaction between P62 and rsgp41 was confirmed, and the interaction was found to be inhibited by only the synthetic peptide P2 sequence that corresponds to the C domain of gp41; neither P1 nor a control peptide inhibited the interaction. Moreover, like rsgp41, P2 was able to bind P62 whereas P1 and another recombinant gp41 (aa567-648 that does not include the C domain) were not.


CONCLUSIONS
P62 bound rsgp41 and the synthetic peptide P2. This interaction could be inhibited only by P2. These results indicate that the C domain of HIV-1 gp41 binds P62.
School of Life Science, Tsinghua University, Beijing, China.
Y H
YH
Chen
Y
Y
Xiao
W
W
Wu
J
J
Yang
S
S
Sui
M P
MP
Dierich
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D004797:Enzyme-Linked Immunosorbent Assay; D015483:HIV Antibodies / Q000276:immunology / Q000378:metabolism; D015700:HIV Envelope Protein gp41 / Q000378:metabolism*; D015497:HIV-1 / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011817:Rabbits; D015728:Receptors, HIV / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D000071456:Sequestosome-1 Protein; D020349:Surface Plasmon Resonance
D048868:Adaptor Proteins, Signal Transducing; D015483:HIV Antibodies; D015700:HIV Envelope Protein gp41; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D010455:Peptides; D015728:Receptors, HIV; D011994:Recombinant Proteins; D000071456:Sequestosome-1 Protein; C101343:Sqstm1 protein, mouse