Nomenclature: C57BL/6-Rara^tm1.1Ybe

• The targeting strategy allows the generation of a conditional Knock-Out (KO) and a constitutive KO of the Rara alleles. This model carries the conditional allele.
• Rara exon 2 contains the translation initiation site. Exon 3 has been flanked by LoxP sites (size of loxP-flanked region 1.7 kb). Positive selection markers have been flanked by FRT (Neomycin resistance - NeoR) and F3 (Puromycin resistance - PuroR) sites and inserted into intron 2 and intron 3, respectively.
• The constitutive KO allele can be obtained after Cre-mediated recombination. Deletion of exon 3 should result in loss of function of the Rara gene by deleting part of the DNA-binding domain and by generating a frameshift from exon 2 to exon 4 (premature Stop codon in exon 5). In addition, the resulting transcript may be a target for Non-sense Mediated RNA Decay and may therefore not be expressed at a significant level.

Origin:

The RARa mouse was developed at Taconic Biosciences on behalf of the National Institute of Health in 2010. The model was generated via transfection of mouse ES cells to introduce a targeting vector via homologous recombination. Targeting vector was generated using BAC clones from the C57BL/6J RPCI-23 BAC library and was be transfected into Taconic C57BL/6NTac ES cell line. Taconic received cryopreserved donor material from NIAID in 2023.