Ppm1d^tm2.1Ble

A loxP site was inserted into intron 5 and a second loxP site, three copies of SV40 poly(A) signal sequences, an FRT site flanked neomycin resistance gene cassette, followed by a third loxP site, the 3' end of intron 5 and a modified copy of exon 6 were inserted into the 3' UTR of the endogenous exon 6. The modification involves changing threonine codon 476 (ACT) to a stop codon (TGA) (p.T476*) and inserting sequence TTAATTAA downstream for stop codons in the other two reading frames. The neo cassette was removed through subsequent Flp-mediated recombination. Cre recombinase-mediated excision of the floxed endogenous exon 6 enables expression of the modified exon that is analogous to the somatic modifications commonly observed in humans. (J:343530)