Zbtb7b^tm2Litt

Exons 2 and 3 were replaced with enhanced green fluorescent protein (EGFP) coding sequence followed by the SV40 polyadenlyation signal. During the gene targeting, a loxP-flanked PGK-neomycin cassette was inserted approximately 1.1 kb upstream of the initiation codon in the sense orientation. The PGK-neomycin cassette was deleted in vivo by crossing to EIIa-cre mice and a single loxP site remains. In T lymphocytes of heterozygotes, GFP is specifically expressed in CD4 cells. In homozygotes, B220+ cells also express GFP. (J:141144, J:141519)