The targeting vector is designed with, from 5' to 3', a CMV-IE enhancer/chicken beta-actin/rabbit beta-globin hybrid promoter (from pCAGGS), a floxed-STOP neomycin cassette and polyA sequence, a bacterial birA (biotin ligase) gene, an internal ribosome entry site (IRES), and an enhanced green fluorescence protein (EGFP). This targeting vector was inserted into the Gt(ROSA)26Sor locus. (J:240794)