Insm1^tm1Cbm

An NLS-lacZ gene followed by a self-excising protamine-cre neomycin selection cassette was fused in-frame to the initiation codon of the gene. Following passage through the male germline of the founder chimeric mouse, the neomycin selection cassette was deleted, leaving the lacZ gene and a single loxP site in place. Beta-galactosidase is expressed from this allele under the control of the endogenous promoter. (J:112173)