Hand2^tm2Zllr

Double recombinase mediated cassette exchange (dRMCE) was used to replace exon 1 of the endogenous gene with a flag epitope tagged exon1. An unmodified exon 2 replaced endogenous exon 2 and a attB/attP flanked PGK-hygro selection cassette was inserted at the same time. Modification was carried out in Hand2 ES cells in which exons 1 and 2 were flanked by loxP sites and an FRT flanked neomycin cassette was inserted downstream. Replacement was accomplished by simultaneous cre and flp recombinase expression in the ES cells. (J:201720)