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Structure of human complement C8, a precursor to membrane attack.

ABSTRACT: Complement component C8 plays a pivotal role in the formation of the membrane attack complex (MAC), an important antibacterial immune effector. C8 initiates membrane penetration and coordinates MAC pore formation. High-resolution structures of C8 subunits have provided some insight into the function of the C8 heterotrimer; however, there is no structural information describing how the intersubunit organization facilitates MAC assembly. We have determined the structure of C8 by electron microscopy and fitted the C8?-MACPF (membrane attack complex/perforin)-C8? co-crystal structure and a homology model for C8?-MACPF into the density. Here, we demonstrate that both the C8? protrusion and the C8?-MACPF region that inserts into the membrane upon activation are accessible.

SUBMITTER: Bubeck D

PROVIDER: S-EPMC3021121 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Structure of human complement C8, a precursor to membrane attack.

Bubeck Doryen D Roversi Pietro P Donev Rossen R Morgan B Paul BP Llorca Oscar O Lea Susan M SM

Journal of molecular biology 20101110 2

Complement component C8 plays a pivotal role in the formation of the membrane attack complex (MAC), an important antibacterial immune effector. C8 initiates membrane penetration and coordinates MAC pore formation. High-resolution structures of C8 subunits have provided some insight into the function of the C8 heterotrimer; however, there is no structural information describing how the intersubunit organization facilitates MAC assembly. We have determined the structure of C8 by electron microscop ...[more]

PMID: 21073882

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Structure of human C8 protein provides mechanistic insight into membrane pore formation by complement.

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2024-06-17 | GSE268767 | GEO

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