Stx3^{Gt(EUCE320f12)1.2Hmgu}

A gene trap cassette flanked by inversely oriented pairs of the heterotypic FRT/F3 and lox511/loxP recombinase target sequences was inserted in intron 1 of the gene. Expression of FLP recombinase inverted the gene trap from its sense (mutagenic) orientation to antisense allowing expression of the gene (floxed allele). Subsequent Cre expression in the germline reinduced and fixed the mutation by the reinversion of gene trap to its sense orientation, generating a knockout allele. (J:275367)