Assembly of C1 and the MBL- and ficolin-MASP complexes: structural insights.
The classical pathway C1 complex, and the MBL-MASP and ficolin-MASP complexes involved in activation of the lectin pathway have several features in common. Both types of complexes are assembled from two subunits: an oligomeric recognition protein (C1q, MBL, L-, H- or M-ficolin), and a protease component, which is either a tetramer (C1s-C1r-C1r-C1s) or a dimer ((MASP)(2)). Recent functional and 3-D structural investigations have revealed that C1r/C1s and the MASPs associate through a common mechanism involving their N-terminal CUB1-EGF region. In contrast, the C1s-C1r-C1r-C1s tetramer and the (MASP)(2) dimers appear to have evolved distinct strategies to associate with their partner proteins. The purpose of this article is to review these recent advances.
Gaboriaud
Christine
C
Laboratoire de Cristallographie et Cristallogénèse des Protéines, France.
Teillet
Florence
F
Gregory
Lynn A
LA
Thielens
Nicole M
NM
Arlaud
Gérard J
GJ
D000818:Animals; D003172:Complement C1 / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D037102:Lectins / Q000737:chemistry / Q000378:metabolism*; D037601:Mannose-Binding Lectin / Q000737:chemistry / Q000378:metabolism*; D050606:Mannose-Binding Protein-Associated Serine Proteases / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D011485:Protein Binding; D000097604:Ficolins
D003172:Complement C1; D037102:Lectins; D037601:Mannose-Binding Lectin; D050606:Mannose-Binding Protein-Associated Serine Proteases; D000097604:Ficolins