Esr1^tm1Ksk

Insertion of a PGK-neomycin resistance cassette into exon 2 disrupted the reading frame downstream of the ATG start site. ELISA studies using antibodies to the carboxy terminus detected low concentrations of endogenous protein in uterine tissue from homozygous mutant mice. RT-PCR analysis detected two truncated mutant transcripts in uterine tissue from homozygous mice. Western blot analysis detected a 61 kDa protein in uterine tissue from homozygotes. Transient transfection assays confirmed that this protein retains some transactivation activity in the presence of estradiol. (J:16338, J:105821, J:112080)