5cis
The CUB1-EGF-CUB2 domains of rat MBL-associated serine protease-2 (MASP-2) bound to Ca2+The CUB1-EGF-CUB2 domains of rat MBL-associated serine protease-2 (MASP-2) bound to Ca2+
Structural highlights
FunctionMASP2_RAT Serum protease that plays an important role in the activation of the complement system via mannose-binding lectin. After activation by auto-catalytic cleavage it cleaves C2 and C4, leading to their activation and to the formation of C3 convertase. Publication Abstract from PubMedThe lectin pathway of complement is activated by complexes comprising a recognition component (mannose-binding lectin, serum ficolins, collectin-LK or collectin-K1) and a serine protease (MASP-1 or MASP-2). MASP-1 activates MASP-2, and MASP-2 cleaves C4 and C4b-bound C2. To clarify activation, new crystal structures of Ca2+-bound MASP dimers were determined, together with their solution structures from X-ray scattering, analytical ultracentrifugation, and atomistic modeling. Solution structures of the CUB1-EGF-CUB2 dimer of each MASP indicate that the two CUB2 domains were tilted by as much as 90 degrees compared with the crystal structures, indicating considerable flexibility at the EGF-CUB2 junction. Solution structures of the full-length MASP dimers in their zymogen and activated forms revealed similar structures that were much more bent than anticipated from crystal structures. We conclude that MASP-1 and MASP-2 are flexible at multiple sites and that this flexibility may permit both intra- and inter-complex activation. Flexibility in Mannan-Binding Lectin-Associated Serine Proteases-1 and -2 Provides Insight on Lectin Pathway Activation.,Nan R, Furze CM, Wright DW, Gor J, Wallis R, Perkins SJ Structure. 2017 Jan 18. pii: S0969-2126(16)30404-X. doi:, 10.1016/j.str.2016.12.014. PMID:28111019[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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