title: Ubiquitous expression of the monomeric red fluorescent protein mCherry in transgenic mice.
abstract: The use of the green fluorescent protein (GFP) to label specific cell types and track gene expression in animal models, such as mice, has evolved to become an essential tool in biological research. Transgenic animals expressing genes of interest linked to GFP, either as a fusion protein or transcribed from an internal ribosomal entry site (IRES) are widely used. Enhanced GFP (eGFP) is the most common form of GFP used for such applications. However, a red fluorescent protein (RFP) would be highly desirable for use in dual-labeling applications with GFP derived fluorescent proteins, and for deep in vivo imaging of tissues. Recently, a new generation of monomeric (m)RFPs, such as monomeric (m)Cherry, has been developed that are potentially useful experimentally. mCherry exhibits brighter fluorescence, matures more rapidly, has a higher tolerance for N-terminal fusion proteins, and is more photostable compared with its predecessor mRFP1. mRFP1 itself was the first true monomer derived from its ancestor DsRed, an obligate tetramer in vivo. Here, we report the successful generation of a transgenic mouse line expressing mCherry as a fluorescent marker, driven by the ubiquitin-C promoter. mCherry is expressed in almost all tissues analyzed including pre- and post-implantation stage embryos, and white blood cells. No expression was detected in erythrocytes and thrombocytes. Importantly, we did not encounter any changes in normal development, general physiology, or reproduction. mCherry is spectrally and genetically distinct from eGFP and, therefore, serves as an excellent red fluorescent marker alone or in combination with eGFP for labelling transgenic animals.
authors.affiliation: British Columbia Cancer Research Centre, Vancouver BC, V5Z 1L3, Canada.
authors.forename: Dieter
authors.initials: D
authors.lastname: Fink
authors.forename: Stefan
authors.initials: S
authors.lastname: Wohrer
authors.forename: Martin
authors.initials: M
authors.lastname: Pfeffer
authors.forename: Tabitha
authors.initials: T
authors.lastname: Tombe
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ong
authors.forename: Poul H B
authors.initials: PH
authors.lastname: Sorensen
mesh_terms: D000818:Animals; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D005838:Genotype; D007962:Leukocytes / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D000097573:Red Fluorescent Protein
chemical_list: D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein