RCL-Mito-Dendra2 Mouse

This strain is a fluorescently labeled model carrying a conditionally expressed mitochondria-targeted photoconvertible fluorescent protein (Mito-Dendra2) reporter gene expression element. The expression of this reporter gene is regulated by the CAG promoter and conditionally blocked by a loxP-Stop-loxP element. In the absence of Cre recombinase, Mito-Dendra2 expression is suppressed. However, when Cre recombinase is present, the loxP-Stop-loxP sequence is excised, allowing the CAG promoter to drive Mito-Dendra2 expression. The CAG promoter is constructed by integrating the chicken β-actin gene promoter, the cytomegalovirus (CMV) early enhancer, the rabbit β-actin gene splice acceptor, and the bovine globin polyA signal, known for its strong and stable real-time gene expression in various mammalian cells, making it a popular choice for driving gene expression in transgenic models. The Mito-Dendra2 protein specifically localizes to mitochondria because of a mitochondrial localization sequence (Mito) fused to its N-terminus. When it's in its unconverted state, this fluorescent protein emits green fluorescence (with excitation/emission peaks around 490/507 nm). If it's excited with a specific wavelength, usually 405 nm, it undergoes irreversible photoconversion to a state that emits red fluorescence (with excitation/emission peaks around 553/573 nm) ^[1]. This ability to photoconvert makes Mito-Dendra2 an ideal tool for studying mitochondrial biological processes. These include, but are not limited to, mitochondrial dynamics (like fusion and fission), mitochondrial transport, and mitophagy. It offers a powerful way to perform real-time tracking and fate tracing of mitochondria in both live cells and living animals.

RCL-Mito-Dendra2 mice are constructed by integrating the CAG promoter-loxP-PGK-Neo-6xSV40 pA-loxP-Kozak-Mito-Dendra2-BGH pA gene expression cassette into intron 1 of the mouse Rosa26 safe harbor locus using gene editing technology. The Dendra2 protein can specifically localize to mitochondria within cells for conditional expression.