title: Generation of a floxed allele of Smad5 for cre-mediated conditional knockout in the mouse.
abstract: Smad5 is a member of the Smad family of intracellular mediators of BMP signals and in endothelial cells of TGF-beta signals. We and others previously showed that loss of Smad5 in the mouse results in embryonic lethality (between E9.5-E11.5) due to multiple embryonic and extraembryonic defects. To circumvent the early embryonic lethality and to allow tissue- and time-specific Smad5 inactivation, we created a conditional Smad5 allele in the mouse. Floxed Smad5 (Smad5(flE2,Neo/flE2,Neo)) mice were generated in which both exon2 and the Neo-cassette were flanked by loxP sites. Here we demonstrate that embryos with ubiquitous Cre-mediated deletion of Smad5 (Smad5(flDeltaE2/flDeltaE2)) phenocopy the conventional Smad5 knockout mice. Smad5(flE2/flE2) mice are now available and will be a valuable tool to analyze the role of Smad5 beyond its crucial early embryonic function throughout development and postnatal life.
mesh_terms: D000483:Alleles; D000818:Animals; D001665:Binding Sites; D015139:Blotting, Southern; D004268:DNA-Binding Proteins / Q000235:genetics*; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D005091:Exons; D005822:Genetic Vectors; D006579:Heterozygote; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D008957:Models, Genetic; D045283:Natriuretic Agents / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics*; D016133:Polymerase Chain Reaction; D051902:Smad5 Protein; D013234:Stem Cells / Q000166:cytology; D013997:Time Factors; D015534:Trans-Activators / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D045283:Natriuretic Agents; D010750:Phosphoproteins; D051902:Smad5 Protein; C497798:Smad5 protein, mouse; D015534:Trans-Activators; D016212:Transforming Growth Factor beta