Dnmt1^tm2Jrc

Three point mutations were introduced changing the initiation codon in exon 1s into an EcoRV site. The Pgk1-neo selection cassette was removed by transient Cre-mediated recombination in the ES cells. The point mutations resulted in transcripts initiated from exon 1s being translated into the splice form Dnmt1o rather than Dnmt1. In spleens from heterozygous mice the wild-type and mutant transcripts are expressed at equal levels. However, methyltransferase activity in the spleen is increased about 2.7- and 4.5-fold (compared to wild-type mice) in heterozygous and homozygous mice, respectively. (J:126389)