Identification of amino acids involved in the binding of hMIP-1 alpha to CC-CKR1, a MIP-1 alpha receptor found on neutrophils.
Human macrophage inflammatory protein-1alpha (hMIP-1alpha) and human macrophage inflammatory protein-1beta (hMIP-1beta) are chemokines involved in a diverse range of immunological effects. Both hMIP-1alpha and hMIP-1beta are involved in the activation of monocytes and THP-1 cells probably through a common receptor(s). However, only hMIP-1alpha can bind to neutrophils with high affinity, presumably through CC-CKR1 (CKR1). Since the structure of these two proteins is highly conserved, non-conserved amino acids must define the disparate binding patterns that these two proteins exhibit. Measurements of binding, chemotaxis and calcium influx conducted with hMIP-1alpha and hMIP-1beta chimeric proteins and mutants show that two amino acids (37K and 43L) are important in the binding and signaling of hMIP-1alpha through CKR1. Furthermore, we also show that mutations of the three charged amino acids at the C-terminus of hMIP-1alpha and hMIP-1beta (amino acids 61, 65 and 67), do not adversely affect the binding to THP-1 cells.
Neurobiotechnology Center, The Ohio State University, Columbus 53210, USA.
J M
JM
Crisman
P J
PJ
Elder
N M
NM
Wilkie
P E
PE
Kolattukudy
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D054407:Chemokine CCL4; D006801:Humans; D020014:K562 Cells; D007930:Leucine / Q000378:metabolism; D008239:Lysine / Q000378:metabolism; D019402:Macrophage Inflammatory Proteins / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000378:metabolism*; D011485:Protein Binding; D019707:Receptors, Chemokine / Q000302:isolation & purification / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D020298:U937 Cells
D000596:Amino Acids; D054407:Chemokine CCL4; D019402:Macrophage Inflammatory Proteins; D019707:Receptors, Chemokine; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; C080633:macrophage inflammatory protein 1alpha receptor; D007930:Leucine; D008239:Lysine; D002118:Calcium