The Membrane Attack Complex/Perforin (MACPF) superfamily , sometimes referred to as the MACPF/CDC superfamily, is named after a domain that is common to the membrane attack complex (MAC) proteins of the complement system (C6, C7, C8α, C8β and C9 ) and perforin (PF). Members of this protein family are pore-forming toxins (PFTs) . In eukaryotes, MACPF proteins play a role in immunity and development.
22-683: C9 , C09 or C-9 may refer to: Biology, medicine, and chemistry [ edit ] C9 ( Complement component 9 ), a protein ATC code C09 , a subgroup of the Anatomical Therapeutic Chemical Classification System C09, ICD-10 code for malignant neoplasm of tonsil Carbon-9 (C-9 or C), an isotope of carbon Military and weapons [ edit ] Hi-Point Models C9 and C9 Comp handguns C9 LMG , Canadian light machine gun C9, an ID for
44-641: A Le Mans racing car C9 engine, by Caterpillar Inc. C-9 (Cercanías Madrid) , a commuter rail line in Madrid LNER Class C9 , a class of 2 British steam locomotives rebuilt from C7s in 1931 SL C9 , a type of rolling stock used in the Stockholm metro Other uses [ edit ] C9, an ISO 216 standard paper size C9, a holiday light bulb size C9, a sportswear line by Champion See also [ edit ] 9C (disambiguation) [REDACTED] Topics referred to by
66-543: A MACPF protein, however, this molecule appears non-lytic. The X-ray crystal structure of Plu-MACPF, a protein from the insect pathogenic enterobacteria Photorhabdus luminescens has been determined (figure 1). [5] These data reveal that the MACPF domain is homologous to pore forming cholesterol dependent cytolysins (CDC's) from gram-positive pathogenic bacteria such as Clostridium perfringens (which causes gas gangrene ). The amino acid sequence identity between
88-562: A South Korean entertainment company and record label Transportation [ edit ] Cierva C.9 , a 1927 British experimental autogyro HMS C9 , a British submarine Ford C-9 , a US military designation for the Ford Trimotor aircraft McDonnell Douglas C-9 , a US Air Force transport aircraft based on the civilian DC-9 USS Montgomery (C-9) , a US Navy cruiser C9, the IATA code for Cirrus Airlines Sauber C9 ,
110-407: A bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens was determined ( PDB : 2QP2 ). The MACPF domain is structurally similar to pore-forming cholesterol-dependent cytolysins from gram-positive bacteria , suggesting that MACPF proteins create pores and disrupt cell membranes similar to cytolysin. A representative list of proteins belonging to the MACPF family can be found in
132-446: A family of pore forming toxins previously thought to only exist in bacteria. As of early 2016, there are three families belonging to the MACPF superfamily: Proteins containing MACPF domains play key roles in vertebrate immunity, embryonic development, and neural-cell migration. The ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. The crystal structure of
154-629: A large pore that punches a hole in the outer membrane of gram-negative bacteria . Perforin is stored in granules within cytotoxic T-cells and is responsible for killing virally infected and transformed cells. Perforin functions via two distinct mechanisms. Firstly, like C9, high concentrations of perforin can form pores that lyse cells. Secondly, perforin permits delivery of the cytotoxic granzymes A and B into target cells. Once delivered, granzymes are able to induce apoptosis and cause target cell death. The plant protein CAD1 ( TC# 1.C.39.11.3 ) functions in
176-628: Is a stub . You can help Misplaced Pages by expanding it . MACPF Archetypal members of the family are complement C9 and perforin , both of which function in human immunity . C9 functions by punching holes in the membranes of Gram-negative bacteria. Perforin is released by cytotoxic T cells and lyses virally infected and transformed cells. In addition, perforin permits delivery of cytotoxic proteases called granzymes that cause cell death . Deficiency of either protein can result in human disease. Structural studies reveal that MACPF domains are related to cholesterol-dependent cytolysins (CDCs),
198-427: Is different from Wikidata All article disambiguation pages All disambiguation pages Complement component 9 5FMW 735 12279 ENSG00000113600 ENSMUSG00000022149 P02748 P06683 NM_001737 NM_013485 NM_001368420 NM_001368421 NP_001728 NP_038513 NP_001355349 NP_001355350 Complement component 9 ( C9 ) is a MACPF protein involved in
220-546: Is involved in sea urchin ( Heliocidaris erythrogramma ) development. Drosophila Torso-like protein ( TC# 1.C.39.15.1 ), which controls embryonic patterning, also contains a MACPF domain. Its function is implicated in a receptor tyrosine kinase signaling pathway that specifies differentiation and terminal cell fate. Functionally uncharacterised MACPF proteins are sporadically distributed in bacteria. Several species of Chlamydia contain MACPF proteins. The insect pathogenic bacteria Photorhabdus luminescens also contains
242-644: Is the site where the majority of complement components are produced and expressed, but C9 can also be found in other tissues. It is a single-chain glycoprotein with a four domain structure arranged in a globular bundle. MAC formation starts with the assembly of a tetrameric complex with the complement components C6, C7, C8, and C5b. The final step of MAC on target cell surfaces involves the polymerization of C9 molecules bound to C5b8 forming C5b-9. C9 molecules allow cylindrical, asymmetrical transmembrane pores to form. The overall complex belongs to MAC/perforin-like (MACPF)/CDC superfamily. Pore formation involves binding
SECTION 10
#1732772321118264-596: The Transporter Classification Database . Many proteins belonging to the MACPF superfamily play key roles in plant and animal immunity. Complement proteins C6-C9 all contain a MACPF domain and assemble into the membrane attack complex. C6, C7 and C8β appear to be non-lytic and function as scaffold proteins within the MAC. In contrast both C8α and C9 are capable of lysing cells. The final stage of MAC formation involves polymerisation of C9 into
286-412: The complement system , which is part of the innate immune system . Once activated, about 12-18 molecules of C9 polymerize to form pores in target cell membranes , causing lysis and cell death. C9 is one member of the complement membrane attack complex (MAC), which also includes complement components C5b , C6 , C7 and C8 . The formation of the MAC occurs through three distinct pathways:
308-411: The lipocalin family and interacts with C8α. The binding site on C8α is known, however, the precise role of C8γ in the MAC remains to be understood. Deficiency of C9, or other components of the MAC results in an increased susceptibility to diseases caused by gram-negative bacteria such as meningococcal meningitis . Overactivity of MACPF proteins can also cause disease. Most notably, deficiency of
330-550: The membrane of the target cell. Like CDC's MACPF proteins are thus β-pore forming toxins that act like a molecular hole punch. Other crystal structures for members of the MACPF superfamily can be found in RCSB: i.e., 3KK7 , 3QOS , 3QQH , 3RD7 , 3OJY Complement regulatory proteins such as CD59 function as MAC inhibitors and prevent inappropriate activity of complement against self cells (Figure 3). Biochemical studies have revealed
352-551: The C9 molecules to the target membrane, membrane molecules forming a pre-pore shape, and conformational change in the TMH1, the first transmembrane region, and TMH2, the second transmembrane region. The formations of pores leads to the killing of foreign pathogens and infected host cells. C9 was found to be the most strongly under expressed serum protein in men who achieved longevity, compared to men who did not. This immunology article
374-579: The German Nachtjagdgeschwader 5 air squadron in World War II Music [ edit ] C9, a note five octaves above Middle C C9, a C ninth chord Organizations [ edit ] Cloud9 , an American esports organization C9 League , an association of Chinese universities The Council of Cardinal Advisers , an advisory body to the pope, originally comprising nine members C9 Entertainment ,
396-405: The classical, alternative, and lectin pathways. Pore formation by C9 is an important way that bacterial cells are killed during an infection, and the target cell is often covered in multiple MACs. The clinical impact of a deficiency in C9 is an infection with the gram-negative bacterium Neisseria meningitidis . C9 genes include 11 exons and 10 introns when found in fish. In fish, the liver
418-466: The peptide sequences in C8α and C9 that bind to CD59. Analysis of the MACPF domain structures reveals that these sequences map to the second cluster of helices that unfurl to span the membrane. It is therefore suggested that CD59 directly inhibits the MAC by interfering with conformational change in one of the membrane spanning regions. Other proteins that bind to the MAC include C8γ. This protein belongs to
440-521: The plant immune response to bacterial infection. The sea anemone Actineria villosa uses a MACPF (AvTX-60A; TC# 1.C.39.10.1 )protein as a lethal toxin. MACPF proteins are also important for the invasion of the Malarial parasite into the mosquito host and the liver. Not all MACPF proteins function in defence or attack. For example, astrotactin-1 ( TC# 9.B.87.3.1 ) is involved in neural cell migration in mammals and apextrin ( TC# 1.C.39.7.4 )
462-447: The same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=C9&oldid=1191365329 " Category : Letter–number combination disambiguation pages Hidden categories: Short description
SECTION 20
#1732772321118484-480: The two families is extremely low, and the relationship is not detectable using conventional sequence based data mining techniques. It is suggested that MACPF proteins and CDCs form pores in the same way (figure 1). Specifically it is hypothesised that MACPF proteins oligomerise to form a large circular pore (figure 2). A concerted conformational change within each monomer then results in two α-helical regions unwinding to form four amphipathic β-strands that span
#117882