a photoprotein in mouse embryonic stem cells measures ca2+ mobilization in cells and in animals就是在小鼠胚胎干细胞的措施ca2 +动员在细胞和动物.pdfVIP

A Photoprotein in Mouse Embryonic Stem Cells Measures Ca2+ Mobilization in Cells and in Animals 1 1 2 1 1 3 Silvia Cainarca *, Simone Fenu , Cinzia Ferri , Cinzia Nucci , Patrizia Arioli , Andrea Menegon , Lorenzo 4 1 2 1 Piemonti , Stefan Lohmer , Lawrence Wrabetz , Sabrina Corazza 1 Axxam SpA, Milan, Italy, 2 Division of Genetics and Cell Biology, San Raffaele Scientific Institute, DIBIT, Milan, Italy, 3 ALEMBIC (Advanced Light and Electron Microscopy Bio-Imaging Centre), San Raffaele Scientific Institute, Milan, Italy, 4 San Raffaele Diabetes Research Institute (HSR-DRI), San Raffaele Scientific Institute, Milan, Italy 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 Ca2+-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, en