A floxed and FRT flanked neo cassette was inserted in intron 2 and a third loxP site was inserted 3' of exon 5. Mice carring this floxed allele were then crossed to mice carrying Tg(EIIa-cre)C5379Lmgd to excise exons 3-5 which code for amino acid residues 51-310. This results in the deletion of the interactin domains for TRAF2 and RIP (receptor interacting domain). (J:139031)