Constituent of the membrane attack complex (MAC) that plays a key role in the innate and adaptive immune response by forming pores in the plasma membrane of target cells. C7 serves as a membrane anchor. Monomer or dimer; as a C5b-7 complex it can also form multimeric rosettes. MAC assembly is initiated by proteolytic cleavage of C5 into C5a and C5b. C5b binds sequentially C6, C7, C8 and multiple copies of the pore-forming subunit C9. C7 has 28 disulfide bridges. C-, N- and O-glycosylated. O-glycosylated with core 1 or possibly core 8 glycans. Disease susceptibility is associated with variants affecting the gene represented in this entry. Belongs to the complement C6/C7/C8/C9 family. C7 mutation db