RT info:eu-repo/semantics/article T1 GFP-Aequorin Protein Sensor for Ex Vivo and In Vivo Imaging of Ca2+ Dynamics in High-Ca2+ Organelles A1 Navas Navarro, Paloma A1 Rojo Ruiz, Jonathan A1 Rodríguez Prados, Macarena A1 Ganfornina Álvarez, María Dolores A1 Looger, Loren L. A1 Alonso Alonso, María Teresa A1 García-Sancho Martín, Francisco Javier K1 Calcio K1 Calcium AB Proper functioning of organelles such as the ER or the Golgi apparatus requires luminal accumulation of Ca2+ at high concentrations. Here we describe a ratiometric low-affinity Ca2+ sensor of the GFP-aequorin protein (GAP) family optimized for measurements in high-Ca2+ concentration environments. Transgenic animals expressing the ER-targeted sensor allowed monitoring of Ca2+ signals inside the organelle. The use of the sensor was demonstrated under three experimental paradigms: (1) ER Ca2+ oscillations in cultured astrocytes, (2) ex vivo functional mapping of cholinergic receptors triggering ER Ca2+ release in acute hippocampal slices from transgenic mice, and (3) in vivo sarcoplasmic reticulum Ca2+ dynamics in the muscle of transgenic flies. Our results provide proof of the suitability of the new biosensors to monitor Ca2+ dynamics inside intracellular organelles under physiological conditions and open an avenue to explore complex Ca2+ signaling in animal models of health and disease. PB Elsevier SN 2451-9456 YR 2016 FD 2016 LK http://uvadoc.uva.es/handle/10324/35193 UL http://uvadoc.uva.es/handle/10324/35193 LA eng NO Cell Chemical Biology, 2016, Volume 23, Issue 6, Pages 738-745 NO Producción Científica DS UVaDOC RD 20-abr-2024