Creb1^tm4Gsc

A serine to alanine substitution at amino acid 142 (S142A) was introduced to exon 8 and a floxed TK-neo cassette was inserted into the upstream intron via homologous recombination. Removal of the TK-neo cassette was achieved by transient expression of cre recombinase in correctly targeted ES cells. The presence of the S142A mutation was verified by sequencing of RT-PCR products from heterozygous animals. Immunohistochemistry of brain sections from homozygous mutant animals demonstrates the absence of phosphorylation at serine 142. The gene expression pattern of homozygous mutants is similar to that of wild-type animals. (J:75993)