Title: Perforin
Additional Names: Cytolysin; pore-forming protein; PFP; C9-related protein
Literature References: Complement-like protein produced by cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells; released from cytoplasmic granules during the cytolytic process. Perforates the membrane of target cells by forming transmembrane pores that perturb membrane permeability and result in cell lysis. Pore-formation is mediated by the Ca2+-dependent polymerization of perforin within the target cell membrane. Also thought to act as a conduit for the endocytosis of granzymes, serine proteinases produced by cytotoxic lymphocytes, that initiate nuclear disintegration. Glycoprotein; mol wt 66-70 kDa. Identification of pore-forming tubular complexes produced by NK cells: E. R. Podack, G. Dennert, Nature 302, 442 (1983). Partial purification of protein: E. R. Podack, P. J. Konigsberg, J. Exp. Med. 160, 695 (1984). Cloning and amino acid sequence of human perforin: M. G. Lichtenheld et al., Nature 335, 448 (1988); of murine: D. M. Lowrey et al., Proc. Natl. Acad. Sci. USA 86, 247 (1989). Confirmation of biological activity: D. Kägi et al., Nature 369, 31 (1994). Review of structure and function: E. R. Podack, Curr. Top. Microbiol. Immunol. 178, 175-184 (1992); C-C. Liu et al., Immunol. Today 16, 194-201 (1995). |