title: A photoprotein in mouse embryonic stem cells measures Ca2+ mobilization in cells and in animals.
abstract: Exogenous expression of pharmacological targets in transformed cell lines has been the traditional platform for high throughput screening of small molecules. However, exogenous expression in these cells is limited by aberrant dosage, or its toxicity, the potential lack of interaction partners, and alterations to physiology due to transformation itself. Instead, primary cells or cells differentiated from precursors are more physiological, but less amenable to exogenous expression of reporter systems. To overcome this challenge, we stably expressed c-Photina, a Ca(2+)-sensitive photoprotein, driven by a ubiquitous promoter in a mouse embryonic stem (mES) cell line. The same embryonic stem cell line was also used to generate a transgenic mouse that expresses c-Photina in most tissues. We show here that these cells and mice provide an efficient source of primary cells, cells differentiated from mES cells, including cardiomyocytes, neurons, astrocytes, macrophages, endothelial cells, pancreatic islet cells, stably and robustly expressing c-Photina, and may be exploited for miniaturized high throughput screening. Moreover, we provide evidence that the transgenic mice may be suitable for ex-vivo bioimaging studies in both cells and tissues.
authors.affiliation: Axxam SpA, Milan, Italy. silvia.cainarca.sc@axxam.com
authors.forename: Silvia
authors.initials: S
authors.lastname: Cainarca
authors.forename: Simone
authors.initials: S
authors.lastname: Fenu
authors.forename: Cinzia
authors.initials: C
authors.lastname: Ferri
authors.forename: Cinzia
authors.initials: C
authors.lastname: Nucci
authors.forename: Patrizia
authors.initials: P
authors.lastname: Arioli
authors.forename: Andrea
authors.initials: A
authors.lastname: Menegon
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Piemonti
authors.forename: Stefan
authors.initials: S
authors.lastname: Lohmer
authors.forename: Lawrence
authors.initials: L
authors.lastname: Wrabetz
authors.forename: Sabrina
authors.initials: S
authors.lastname: Corazza
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002454:Cell Differentiation; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D008164:Luminescent Proteins / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic
chemical_list: D008164:Luminescent Proteins; D002118:Calcium