TY - JOUR
T1 - Fibrillin-1 and fibulin-2 interact and are colocalized in some tissues
AU - Reinhardt, Dieter P.
AU - Sasaki, Takako
AU - Dzamba, Bette J.
AU - Keene, Douglas R.
AU - Chu, Mon Li
AU - Göhring, Walter
AU - Timpl, Rupert
AU - Sakai, Lynn Y.
PY - 1996
Y1 - 1996
N2 - Microfibrils 10-12 nm in diameter are found in elastic and non-elastic tissues with fibrillin as a major component. Little is known about the supramolecular structure of these microfibrils and the protein interactions it is based on. To identify protein binding ligands of fibrillin-1, we tested binding of recombinant fibrillin-1 peptides to different extracellular matrix proteins in solid phase assays. Among the proteins tested, only fibulin-2 showed significant binding to rF11, the N-terminal half of fibrillin-1, in a calcium-dependent manner. Surface plasmon resonance demonstrated high affinity binding with a K(d) = 56 nM. With overlapping recombinant fibrillin-1 peptides, the binding site for fibulin- 2 was narrowed down to the N terminus of fibrillin-1 (amino acid positions 45-450). Immunofluorescence in tissues demonstrated colocalization of fibrillin and fibulin-2 in skin, perichondrium, elastic intima of blood vessels, and kidney glomerulus. Fibulin-2 was not present in ocular ciliary zonules, tendon, and the connective tissue around kidney tubules and lung alveoli, which all contain fibrillin. Immunogold labeling of fibulin-2 on microfibrils in skin was found preferentially at the interface between microfibrils and the amorphous elastin core, suggesting that in vivo the interaction between fibrillin-1 and fibulin-2 is regulated by cellular expression and deposition as well as by protein-protein interactions.
AB - Microfibrils 10-12 nm in diameter are found in elastic and non-elastic tissues with fibrillin as a major component. Little is known about the supramolecular structure of these microfibrils and the protein interactions it is based on. To identify protein binding ligands of fibrillin-1, we tested binding of recombinant fibrillin-1 peptides to different extracellular matrix proteins in solid phase assays. Among the proteins tested, only fibulin-2 showed significant binding to rF11, the N-terminal half of fibrillin-1, in a calcium-dependent manner. Surface plasmon resonance demonstrated high affinity binding with a K(d) = 56 nM. With overlapping recombinant fibrillin-1 peptides, the binding site for fibulin- 2 was narrowed down to the N terminus of fibrillin-1 (amino acid positions 45-450). Immunofluorescence in tissues demonstrated colocalization of fibrillin and fibulin-2 in skin, perichondrium, elastic intima of blood vessels, and kidney glomerulus. Fibulin-2 was not present in ocular ciliary zonules, tendon, and the connective tissue around kidney tubules and lung alveoli, which all contain fibrillin. Immunogold labeling of fibulin-2 on microfibrils in skin was found preferentially at the interface between microfibrils and the amorphous elastin core, suggesting that in vivo the interaction between fibrillin-1 and fibulin-2 is regulated by cellular expression and deposition as well as by protein-protein interactions.
UR - http://www.scopus.com/inward/record.url?scp=0029761338&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029761338&partnerID=8YFLogxK
U2 - 10.1074/jbc.271.32.19489
DO - 10.1074/jbc.271.32.19489
M3 - Article
C2 - 8702639
AN - SCOPUS:0029761338
SN - 0021-9258
VL - 271
SP - 19489
EP - 19496
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 32
ER -