Fas Apoptotic Inhibitory Molecule 2 (FAIM2)

Somia et al. (1999) established a genetic screen to search for molecules that inhibit the apoptotic signal from the FAS receptor. They isolated a gene, called LFG ('lifeguard'), and found that it is the human homolog of a rat protein, neuromembrane protein-35 (NMP35), described by Schweitzer et al. (1998). The LFG open reading frame encodes a 316-amino acid protein predicted by hydropathy plots to contain 7 membrane-spanning domains. They found that LFG protects cells uniquely from FAS but not from the mechanistically related tumor necrosis factor-alpha death signal. LFG is widely distributed, but remarkably is highly expressed in the hippocampus. LFG can bind to the FAS receptor, but does not regulate FAS expression or interfere with binding of an agonist antibody. Furthermore, LFG does not inhibit binding of FADD to FAS.