Beta 1 integrins mediate chondrocyte interaction with type I collagen, type II collagen, and fibronectin.
Chondrocytes isolated from the cephalic region of sterna from 14-day-old chick embryos used beta 1 integrins and required either Mg2+ or Mn2+ for attachment to plates coated with type I collagen, type II collagen, and fibronectin. beta 1 integrin was concentrated in adhesion plaques of the chondrocytes plated on type I collagen, type II collagen, and fibronectin substrates. Chondrocytes expressed at least 3 alpha-subunits, including alpha 3, alpha 5, and putative alpha 2. alpha 5, but not alpha 3, had a higher molecular weight in chondrocytes than in fibroblasts. Levels of alpha 3 and alpha 5 were about 25-30% of that in fibroblasts. When the chondrocytes were cultured in the presence of ascorbate in suspension, the cells aggregated into clusters. This aggregation was dependent on beta 1 integrin and type II collagen.
Department of Microbiology, School of Medicine, University of Pennsylvania, Philadelphia 19104-6076.
M
M
Enomoto
P S
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Leboy
A S
AS
Menko
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D
Boettiger
D000595:Amino Acid Sequence; D000818:Animals; D002356:Cartilage / Q000378:metabolism*; D002448:Cell Adhesion; D002642:Chick Embryo; D003094:Collagen / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism*; D066298:In Vitro Techniques; D016023:Integrins / Q000378:metabolism*; D008969:Molecular Sequence Data; D009024:Morphogenesis; D010455:Peptides / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism
D003598:Cytoskeletal Proteins; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D016023:Integrins; D010455:Peptides; D011956:Receptors, Cell Surface; D003094:Collagen