Inducible Cre-driven CRTC1-MAML2 Fusion Transgenic Mice

The Cre-regulated CRTC1-MAML2 transgenic mice were crossed with homozygous transgenic MMTV-Cre mice (Tg[MMTV-cre]4Mam/J, 003553, The Jackson Laboratory) to induce expression of the CRTC1-MAML2 fusion transgene in salivary gland. Mice carrying the fusion transgene were identified by PCR as described above. Nontransgenic littermates were used as negative controls.
The Cre-regulated CRTC1-MAML2 transgenic mice were also crossed with the Dcpp1tm1.1 (cre/ERT2)Ovi (028731, Jackson Laboratory; designated as “dCre-ERT2”), and Piptm1.1(cre/ERT2)Ovi (023201, Jackson Laboratory; designated as “pCre-ERT2”). dCre-ERT2 is a tamoxifen–inducible (TAM-inducible) Cre strain in which a fusion of Cre to a mutant form of human estrogen receptor (ERT2) was inserted right after the initiation ATG codon of Dcpp1 exon 1, and its TAM-induced Cre expression was specific to sublingual serous demilune cells and intercalated duct cells in parotid glands (38 (link)). pCre-ERT2 is a TAM-inducible Cre strain in which exon 1 of Pip gene is replaced by Cre-ERT2 fusion, and its TAM-induced Cre expression was specific to acinar cells in submandibular glands (38 (link)). TAM (75 mg/kg body weight) was i.p. injected to mice at about 4 weeks of age once daily for 3 consecutive days.