Endogenous muscle lectin inhibits myoblast adhesion to laminin.
L-14, a dimeric lactose-binding lectin with subunits of 14 kD, is expressed in a wide range of vertebrate tissues. Several functions have been postulated for this lectin, but definitive evidence for a specific biological role has been elusive. In muscle, L-14 is secreted during differentiation and accumulates with laminin in basement membrane surrounding each myofiber. Here we present evidence that laminin is a major glycoprotein ligand for L-14 in differentiating mouse C2C12 muscle cells and that binding of secreted L-14 to polylactosamine oligosaccharides of substrate laminin induces loss of cell-substratum adhesion. These results suggest that one function of L-14 is to regulate myoblast detachment from laminin during differentiation and fusion into tubular myofibers.
Cooper
D N
DN
Department of Psychiatry, University of California, San Francisco 94143.
Massa
S M
SM
Barondes
S H
SH
D000818:Animals; D002448:Cell Adhesion; D002454:Cell Differentiation; D002478:Cells, Cultured; D006023:Glycoproteins / Q000378:metabolism; D007150:Immunohistochemistry; D007797:Laminin / Q000378:metabolism*; D037102:Lectins / Q000502:physiology*; D051379:Mice; D009132:Muscles / Q000166:cytology* / Q000378:metabolism; D011994:Recombinant Proteins / Q000502:physiology; D014162:Transfection
D006023:Glycoproteins; D007797:Laminin; D037102:Lectins; D011994:Recombinant Proteins