TY - JOUR
T1 - Fibronectin self-association is mediated by complementary sites within the amino-terminal one-third of the molecule
AU - Aguirre, Karen M.
AU - McCormick, Richard J.
AU - Schwarzbauer, Jean E.
PY - 1994/11/11
Y1 - 1994/11/11
N2 - The formation of a fibrillar fibronectin (FN) extracellular matrix requires self-association of FN dimers. In this report, we show that the major sites for self-association are the amino-terminal repeats I1-5 and the first type III repeats. Recombinant FNs and fragments were generated by baculovirus expression of cysteine-rich domains and by bacterial expression of type III repeats as fusion proteins with maltose binding protein. When recombinant polypeptides were immobilized on microtiter wells, FN bound to 70-kDa amino-terminal fragment and to fusion proteins containing repeats III1-2 and III1-6 but not to other type III repeats. Similar results were obtained with a gel overlay assay. Binding was concentration-dependent and saturable. The amino-terminal binding site for III1-2 was further localized to repeats I1-5. Therefore, at least two different sites for FN- FN interaction reside near the amino terminus of the molecule. A model for the regulation of FN matrix assembly is proposed based on intramolecular interactions between these amino-terminal sites.
AB - The formation of a fibrillar fibronectin (FN) extracellular matrix requires self-association of FN dimers. In this report, we show that the major sites for self-association are the amino-terminal repeats I1-5 and the first type III repeats. Recombinant FNs and fragments were generated by baculovirus expression of cysteine-rich domains and by bacterial expression of type III repeats as fusion proteins with maltose binding protein. When recombinant polypeptides were immobilized on microtiter wells, FN bound to 70-kDa amino-terminal fragment and to fusion proteins containing repeats III1-2 and III1-6 but not to other type III repeats. Similar results were obtained with a gel overlay assay. Binding was concentration-dependent and saturable. The amino-terminal binding site for III1-2 was further localized to repeats I1-5. Therefore, at least two different sites for FN- FN interaction reside near the amino terminus of the molecule. A model for the regulation of FN matrix assembly is proposed based on intramolecular interactions between these amino-terminal sites.
UR - http://www.scopus.com/inward/record.url?scp=0028043949&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028043949&partnerID=8YFLogxK
M3 - Article
C2 - 7961716
AN - SCOPUS:0028043949
SN - 0021-9258
VL - 269
SP - 27863
EP - 27868
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 45
ER -