. . . . . . "The chemokine receptor CCR5 is posttranslationally modified by sulfation of its N-terminal tyrosines; sulfated tyrosines contribute to the binding of CCR5 to MIP-1 alpha, MIP-1 beta, and HIV-1 gp120/CD4 complexes and to the ability of HIV-1 to enter cells" . "Sulfation of CCR5 by tyrosylprotein sulfotranferase-2 is crucial for mediating interaction with HIV-1 gp120. The pattern and the rate of sulfation for CCR5 depend on the number of amino acids N-terminal of Tyr-3" . "interacts with" .