The structure and function of mammalian membrane-attack complex/perforin-like proteins

Abstract

The membrane-attack complex (MAC) of complement pathway and perforin (PF) are important tools deployed by the immune system to target pathogens. Both perforin and the C9 component of theMAC contain a common 'MACPF' domain and form pores in the cell membrane as part of their function. The MAC targets gram-negative bacteria and certain pathogenic parasites, while perforin, released by natural killer cells or cytotoxic T lymphocytes (CTLs), targets virus-infected and transformed host cells (1). Remarkably, recent structural studies show that the MACPF domain is homologous to the pore-forming portion of bacterial cholesterol-dependent cytolysins; these data have provided important insight into t..