title: Visualizing endoderm cell populations and their dynamics in the mouse embryo with aHex-tdTomatoreporter.
abstract: Live imaging is the requisite tool for studying cell behaviors driving embryonic development and tissue formation. Genetically encoded reporters expressed under cell type-specificcis-regulatory elements that drive fluorescent protein expression at sufficient levels for visualization in living specimens have become indispensable for these studies. Increasingly dual-color (red-green) imaging is used for studying the coordinate behaviors of two cell populations of interest, identifying and characterizing subsets within broader cell populations or subcellular features. Many reporters have been generated using green fluorescent protein (GFP) due to its brightness and developmental neutrality. To compliment the large cohort of available GFP reporters that label cellular populations in early mouse embryos, we have generated a red fluorescent protein (RFP)-based transgenic reporter using the red fluorescent tdTomato protein driven bycis-regulatory elements from the mouseHexlocus. TheHex-tdTomatoreporter predominantly labels endodermal cells. It is a bright RFP-based reporter of the distal visceral endoderm (DVE)/anterior visceral endoderm (AVE), a migratory population within the early post-implantation embryo. It also labels cells of the definitive endoderm (DE), which emerges at gastrulation. Dual-color visualization of these different early endodermal populations will provide a detailed understanding of the cellular behaviors driving key morphogenetic events involving the endoderm.
authors.affiliation: Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.affiliation: Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
authors.forename: Anna-Katerina
authors.initials: AK
authors.lastname: Hadjantonakis
authors.affiliation: Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA nowotscs@mskcc.org.
authors.forename: Sonja
authors.identifier: http://orcid.org/0000-0002-2646-8598
authors.initials: S
authors.lastname: Nowotschin
keywords: AVE; Definitive endoderm; Gastrulation; Hex; Live imaging; Red fluorescent protein; Visceral endoderm