Chondroitin sulfate B exerts its inhibitory effect on secondary lymphoid tissue chemokine (SLC) by binding to the C-terminus of SLC.
We previously reported that certain glycosaminoglycans (GAGs) bind secondary lymphoid tissue chemokine (SLC, CCL21) and that the SLC-binding GAGs, including chondroitin sulfate B (CS B), negatively modulate the function of SLC, although the mechanism remains unknown [J. Biol. Chem. 276 (2001) 5228]. To gain insight into the mechanism of inhibition, we used a C-terminally truncated SLC (SLC-T) that lacked clusters of basic amino acid residues that have been implicated in GAG binding. While SLC-T failed to bind any GAGs, it induced prominent intracellular Ca(2+) mobilization in CC chemokine receptor (CCR) 7-expressing cells, as did wild-type SLC. However, the SLC-T-induced Ca(2+) influx was not inhibited by CS B, unlike the SLC-induced Ca(2+) influx. These results demonstrate the requirement of the C-terminus of SLC for the inhibition of chemokine responses by CS B; that is, CS B exerts its inhibitory effect by binding to the C-terminus of SLC, thus defining the mode of action of CS B on certain chemokines.
Hirose
Jun
J
Molecular and Cellular Recognition, Osaka University Graduate School of Medicine C8, 2-2, Yamada-Oka, Suita, Osaka 565-0871, Japan.
Kawashima
Hiroto
H
Swope Willis
Melissa
M
Springer
Timothy A
TA
Hasegawa
Hitoshi
H
Yoshie
Osamu
O
Miyasaka
Masayuki
M
D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D054421:Chemokine CCL21; D019742:Chemokines, CC / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006224:Cricetinae; D003871:Dermatan Sulfate / Q000378:metabolism / Q000494:pharmacology*; D005260:Female; D005434:Flow Cytometry; D006025:Glycosaminoglycans / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010053:Ovary / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D054400:Receptors, CCR7; D019707:Receptors, Chemokine / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D013329:Structure-Activity Relationship
D054421:Chemokine CCL21; D019742:Chemokines, CC; D006025:Glycosaminoglycans; D054400:Receptors, CCR7; D019707:Receptors, Chemokine; D003871:Dermatan Sulfate; D002118:Calcium