CD46 (membrane cofactor protein) associates with multiple beta1 integrins and tetraspans.
The tetraspans associate with a large number of surface molecules, including a subset of beta1 integrins and, indirectly through CD19, with the complement receptor CD21. To further characterize the tetraspan complexes we have raised and selected monoclonal antibodies (mAb) for their ability to immunoprecipitate a molecule associated with CD9. A unique mAb was identified which recognizes the complement regulator CD46 (membrane cofactor protein). CD46 associated in part with several tetranspans and with all beta1 integrins that were tested (CD29/CD49a, CD29/CD49b, CD29/CD49c, CD29/CD49e, CD29/CD49f) but not with beta4 integrins. These data, together with cross-linking experiments showing the existence in living cells of CD46/integrin complexes, suggest that CD46 associates directly with beta1 integrins and indirectly with tetraspans. CD46 also acts as a receptor for measles virus; however, mAb to various integrins and tetraspans did not modify the virus fusion entry step.
Lozahic
S
S
INSERM U268, Hôpital Paul Brousse, Villejuif, France.
Christiansen
D
D
Manié
S
S
Gerlier
D
D
Billard
M
M
Boucheix
C
C
Rubinstein
E
E
D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000737:chemistry / Q000378:metabolism*; D000954:Antigens, Surface / Q000378:metabolism*; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D003432:Cross-Linking Reagents; D006367:HeLa Cells; D006801:Humans; D039161:Integrin alpha6beta4; D019012:Integrin beta1 / Q000737:chemistry / Q000378:metabolism*; D016023:Integrins / Q000378:metabolism; D008459:Measles virus / Q000472:pathogenicity; D051916:Membrane Cofactor Protein; D008561:Membrane Fusion; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D011485:Protein Binding; D060245:Tetraspanin 29
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000954:Antigens, Surface; C497857:CD46 protein, human; C554869:CD9 protein, human; C554870:Cd9 protein, mouse; D003432:Cross-Linking Reagents; D039161:Integrin alpha6beta4; D019012:Integrin beta1; D016023:Integrins; C497859:Mcp protein, mouse; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins; D060245:Tetraspanin 29