TY - JOUR
T1 - The cartilage-specific fibronectin isoform has a high affinity binding site for the small proteoglycan decorin
AU - Gendelman, Rina
AU - Burton-Wurster, Nancy I.
AU - MacLeod, James N.
AU - Lust, George
PY - 2003/3/28
Y1 - 2003/3/28
N2 - Binding of fibronectin to the small proteoglycan decorin plays an important role in cell differentiation and cell migration. The cartilage-specific (V+C)- fibronectin isoform, in which nucleotides that normally encode the protein segments V, III15, and I10 are spliced out, is one of the major splice variants present in cartilage matrices. Full-length and truncated cDNA constructs were used to express recombinant versions of fibronectin. Results demonstrated that the (V+C)- isoform has a higher affinity for decorin. Dissociation constants for decorin and fibronectin interaction were calculated to be 93 nM for the V+C+ isoform and 24 nM and 223 nM for (V+C)- fibronectin. Because heparin competed with decorin competitively, binding of decorin to fibronectin likely occurs at a heparin-binding region. We propose that alternative splicing of the V and C regions changes the global conformation of fibronectin in such a way that it opens an additional decorin-binding site. This conformational change is responsible for the higher affinity of the (V+C)- fibronectin isoform for decorin.
AB - Binding of fibronectin to the small proteoglycan decorin plays an important role in cell differentiation and cell migration. The cartilage-specific (V+C)- fibronectin isoform, in which nucleotides that normally encode the protein segments V, III15, and I10 are spliced out, is one of the major splice variants present in cartilage matrices. Full-length and truncated cDNA constructs were used to express recombinant versions of fibronectin. Results demonstrated that the (V+C)- isoform has a higher affinity for decorin. Dissociation constants for decorin and fibronectin interaction were calculated to be 93 nM for the V+C+ isoform and 24 nM and 223 nM for (V+C)- fibronectin. Because heparin competed with decorin competitively, binding of decorin to fibronectin likely occurs at a heparin-binding region. We propose that alternative splicing of the V and C regions changes the global conformation of fibronectin in such a way that it opens an additional decorin-binding site. This conformational change is responsible for the higher affinity of the (V+C)- fibronectin isoform for decorin.
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U2 - 10.1074/jbc.M211799200
DO - 10.1074/jbc.M211799200
M3 - Article
C2 - 12482864
AN - SCOPUS:0038515331
SN - 0021-9258
VL - 278
SP - 11175
EP - 11181
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 13
ER -