Ahr^tm4.1Bra

Six nucleotides (GGTACC), coding for amino acids glycine and serine, were inserted between the last residue of the basic domain (arginine-39) and the first residue of the helix-loop-helix domain (aspartate-40). A floxed neo selection cassette was also inserted and the removed via in vivo cre mediated recombination. Western blot analysis confirmed that the level of expression of the mutant protein in livers of homozygotes was similar to expression of the the normal protein in wild-type littermates. When expressed in vitro the mutant protein fails to bind to DNA containing dioxin responsive elements. (J:141978)