Distinct interaction of versican/PG-M with hyaluronan and link protein.
The proteoglycan aggregate is the major structural component of the cartilage matrix, comprising hyaluronan (HA), link protein (LP), and a large chondroitin sulfate (CS) proteoglycan, aggrecan. Here, we found that another member of aggrecan family, versican, biochemically binds to both HA and LP. Functional analyses of recombinant looped domains (subdomains) A, B, and B' of the N-terminal G1 domain revealed that the B-B' segment of versican is adequate for binding to HA and LP, whereas A and B-B' of aggrecan bound to LP and HA, respectively. BIAcore trade mark analyses showed that the A subdomain of versican G1 enhances HA binding but has a negligible effect on LP binding. Overlay sensorgrams demonstrated that versican G1 or its B-B' segment forms a complex with both HA and LP. We generated a molecular model of the B-B' segment, in which a deletion and an insertion of B' and B are critical for stable structure and HA binding. These results provide important insights into the mechanisms of formation of the proteoglycan aggregate and HA binding of molecules containing the link module.
Matsumoto
Kazu
K
Institute for Molecular Science of Medicine, Aichi Medical University, Nagakute, Aichi 480-1195.
Shionyu
Masafumi
M
Go
Mitiko
M
Shimizu
Katsuji
K
Shinomura
Tamayuki
T
Kimata
Koji
K
Watanabe
Hideto
H
D000595:Amino Acid Sequence; D000818:Animals; D015815:Cell Adhesion Molecules / Q000737:chemistry; D002460:Cell Line; D011508:Chondroitin Sulfate Proteoglycans / Q000737:chemistry / Q000378:metabolism*; D002809:Chondroitin Sulfates / Q000378:metabolism; D005822:Genetic Vectors; D006801:Humans; D018960:Hyaluronan Receptors / Q000737:chemistry; D006820:Hyaluronic Acid / Q000737:chemistry / Q000378:metabolism*; D015151:Immunoblotting; D007700:Kinetics; D037181:Lectins, C-Type; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D020349:Surface Plasmon Resonance; D013997:Time Factors; D053675:Versicans
D015815:Cell Adhesion Molecules; D011508:Chondroitin Sulfate Proteoglycans; D018960:Hyaluronan Receptors; D037181:Lectins, C-Type; D011994:Recombinant Proteins; C072273:TNFAIP6 protein, human; C513057:Tnfaip6 protein, mouse; C508322:VCAN protein, human; C508323:Vcan protein, mouse; D053675:Versicans; D006820:Hyaluronic Acid; D002809:Chondroitin Sulfates