The N-terminal globular domain of the laminin alpha1 chain binds to alpha1beta1 and alpha2beta1 integrins and to the heparan sulfate-containing domains of perlecan.
The N-terminal domains VI plus V (62 kDa) and V alone (43 kDa) of the laminin alpha1 chain were obtained as recombinant products and shown to be folded into a native form by electron microscopy and immunological assays. Domain VI alone, which corresponds to an LN module, did not represent an autonomously folding unit in mammalian cells, however. Fragment alpha1VI/V, but not fragment alpha1V, bound to purified alpha1beta1 and alpha2beta1 integrins, to heparin, and to heparan sulfate-substituted domains I and V of perlecan. This localized the binding activities to the LN module, which contains two basic sequences suitable for heparin interactions.
Ettner
N
N
Max-Planck-Institut für Biochemie, Martinsried, Germany.
Göhring
W
W
Sasaki
T
T
Mann
K
K
Timpl
R
R
D000818:Animals; D002460:Cell Line; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D039222:Integrin alpha1beta1; D016023:Integrins / Q000378:metabolism*; D007797:Laminin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D008854:Microscopy, Electron; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D017510:Protein Folding; D011509:Proteoglycans / Q000737:chemistry / Q000378:metabolism*; D038981:Receptors, Collagen; D011993:Recombinant Fusion Proteins
D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D039222:Integrin alpha1beta1; D016023:Integrins; D007797:Laminin; D010446:Peptide Fragments; D011509:Proteoglycans; D038981:Receptors, Collagen; D011993:Recombinant Fusion Proteins; C071927:perlecan; C084098:laminin A