title: Variability of inducible expression across the hematopoietic system of tetracycline transactivator transgenic mice.
abstract: The tetracycline (tet)-regulated expression system allows for the inducible overexpression of protein-coding genes, or inducible gene knockdown based on expression of short hairpin RNAs (shRNAs). The system is widely used in mice, however it requires robust expression of a tet transactivator protein (tTA or rtTA) in the cell type of interest. Here we used an in vivo tet-regulated fluorescent reporter approach to characterise inducible gene/shRNA expression across a range of hematopoietic cell types of several commonly used transgenic tet transactivator mouse strains. We find that even in strains where the tet transactivator is expressed from a nominally ubiquitous promoter, the efficiency of tet-regulated expression can be highly variable between hematopoietic lineages and between differentiation stages within a lineage. In some cases tet-regulated reporter expression differs markedly between cells within a discrete, immunophenotypically defined population, suggesting mosaic transactivator expression. A recently developed CAG-rtTA3 transgenic mouse displays intense and efficient reporter expression in most blood cell types, establishing this strain as a highly effective tool for probing hematopoietic development and disease. These findings have important implications for interpreting tet-regulated hematopoietic phenotypes in mice, and identify mouse strains that provide optimal tet-regulated expression in particular hematopoietic progenitor cell types and mature blood lineages.
authors: Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
authors: Megumi
authors: M
authors: Takiguchi
authors: Lukas E
authors: LE
authors: Dow
authors: Julia E
authors: JE
authors: Prier
authors: Catherine L
authors: CL
authors: Carmichael
authors: Benjamin T
authors: BT
authors: Kile
authors: Stephen J
authors: SJ
authors: Turner
authors: Scott W
authors: SW
authors: Lowe
authors: David C S
authors: DC
authors: Huang
authors: Ross A
authors: RA
authors: Dickins
mesh_terms: D000818:Animals; D019070:Cell Lineage / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000235:genetics; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006413:Hematopoietic System / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics; D013752:Tetracycline / Q000494:pharmacology*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*
chemical_list: D034741:RNA, Small Interfering; D015534:Trans-Activators; D049452:Green Fluorescent Proteins; D013752:Tetracycline