A mart‐1::Cre transgenic line induces recombination in melanocytes and retinal pigment epithelium

Abstract

The number of transgenic mouse lines expressing Cre in either type of pigment cells (melanocytes and retinal pigment epithelium, RPE) is limited, and the available lines do not always offer sufficient specificity. In this study, we addressed this issue and we report on the generation of a MART-1::Cre BAC transgenic mouse line, in which the expression of Cre recombinase is controlled by regulatory elements of the pigment cell-specific gene MART-1 (mlana). When MART-1::Cre BAC transgenic mice were bred with the ROSA26-R reporter line, ß-galactosidase expression was observed in RPE from E12.5 onwards, and in melanocyte precursors from E17.5, indicating that the MART-1::Cre line provides Cre recombinase activity in pigment-producing cells rather than in a particular lineage. In addition, breeding of this mouse line to mice carrying a conditional allele of RBP-Jκ corroborated the reported phenotypes in both pigment cell lineages, inducing hair greying and microphthalmia. Our results thus suggest, that the MART-1::Cre line may serve as a novel and useful tool for functional studies in melanocytes and the RPE.genesis 49:403-409, 2011.

Notch signaling in the pigmented epithelium of the anterior eye segment promotes ciliary body development at the expense of iris formation

“…MART1::Cre (Aydin and Beermann, ) transgenic mice carrying floxed alleles of R26.NICD, Notch1, Notch2, or RBP‐Jk were used. All mice used for breeding and analyses were pigmented ( Tyr + ), non‐agouti (a), and black ( Tyrp1 + ).…”

Coat color dilution in mice because of inactivation of the melanoma antigen MART‐1

“…cDNA samples were used as a template for RT‐PCR analysis. The following primers were used for the RT‐PCR (Aydin and Beermann, 2011): MART‐1 : F, ATTGCTCTGCTTATCGGCTGCT, R, CACCATTCCTCCAATATCCCTCT; tyrosinase : F, AAGTTTACCCAGAAGCCAATG, R, CTGTGGTAGTCGTCTTTGTC; Dct ; F: AGCAGTATGGCTGGAGCACT, R: AGCCCTTTCC‐TCTCCTCTCA; GAPDH : F, CAAGGTCATCCATGACAACTTTG, R, GTCCACCACCCTGTTGCTGTAG.…”

Genetically engineered mouse models of melanoma

“…However, the other promoters mentioned earlier may also drive extra-melanocytic expression of Cre, which may or may not be desirable. For example, Dct, Trp1, and Mlana promoters also drive expression in the retinal pigment epithelium (RPE) [34–37]. MITF-Cre is expressed in the ocular melanoblasts, but not in the RPE, and seems to be highly specific for the melanocytic lineage during embryogenesis and postnatal development [38].…”

“…For example, Dct, Trp1, and Mlana promoters also drive expression in the retinal pigment epithelium (RPE). [34][35][36][37] MITF-Cre is expressed in the ocular melanoblasts, but not in the RPE, and seems to be highly specific for the melanocytic lineage during embryogenesis and postnatal development. 38 Recently, the Mitf-Cre model has been used to drive expression of the G protein subunit a Q (GNAQ) glutamine-to-leucine codon 209 (GNAQ Q209L ) transgene to produce uveal melanoma with 100% penetrance, whereas the Tyr::Cre-ER T2 failed to do so.…”