MACPFmembrane-attack complex / perforin
|SMART accession number:||SM00457|
|Interpro abstract (IPR020864):|
The membrane attack complex/perforin (MACPF) domain is conserved in bacteria, fungi, mammals and plants. It was originally identified and named as being common to five complement components (C6, C7, C8-alpha, C8-beta, and C9) and perforin. These molecules perform critical functions in innate and adaptive immunity. The MAC family proteins and perforin are known to participate in lytic pore formation. In response to pathogen infection, a sequential and highly specific interaction between the constituent elements occurs to form transmembrane channels which are known as the membrane-attack complex (MAC).Only a few other MACPF proteins have been characterised and several are thought to form pores for invasion or protection [(PUBMED:16900325), (PUBMED:17717151), (PUBMED:18440555)]. Examples are proteins from malarial parasites [(PUBMED:15659064)], the cytolytic toxins from sea anemones [(PUBMED:17368498)], and proteins that provide plant immunity [(PUBMED:16900325), (PUBMED:15799997)]. Functionally uncharacterised MACPF proteins are also evident in pathogenic bacteria such as Chlamydia spp [(PUBMED:10608922)] and Photorhabdus luminescens (Xenorhabdus luminescens) [(PUBMED:17717151)].
The MACPF domain is commonly found to be associated with other N- and C-terminal domains, such as TSP1 LDLRA EGF-like,Sushi/CCP/SCR FIMAC or C2. They probably control or target MACPF function [(PUBMED:17717151), (PUBMED:17872444)]. The MACPF domain oligomerizes, undergoes conformational change, and is required for lytic activity.
The MACPF domain consists of a central kinked four-stranded antiparallel beta sheet surrounded by alpha helices and beta strands, forming two structural segments. Overall, the MACPF domain has a thin L-shaped appearance. MACPF domains exhibit limited sequence similarity but contain a signature [YW]-G-[TS]-H-[FY]-x(6)-G-G motif [(PUBMED:17717151), (PUBMED:18440555), (PUBMED:17872444)].
Some proteins known to contain a MACPF domain are listed below:
Click on the following links for more information.
- Evolution (species in which this domain is found)
- Literature (relevant references for this domain)
- Disease (disease genes where sequence variants are found in this domain)
- Metabolism (metabolic pathways involving proteins which contain this domain)
- Structure (3D structures containing this domain)
- Links (links to other resources describing this domain)