Cpa3^tm2Hrr

The endogenous gene has been mutated by homologous recombination to contain two point mutations in exon 11, A1073T and A1139C (per NCBI Entrez mRNA NM_007753), and thus to encode a protein harboring the amino-acid substitutions Tyr356Leu and Glu378Ala, respectively. A single loxP site remains in intron 10. Although western blot analysis of lysates of peritoneal mast cells demonstrates that mast cells from homozygous mutant mice express ~80% as much protein as those from normal mice, the lysates contain no detectable carboxypeptidase activity against the test substrate N-[4-methoxyphenylazoformyl]-Phe-OH. (J:125964)