title: Using aequorin probes to measure Ca2+in intracellular organelles.
abstract: Aequorins are excellent tools for measuring intra-organellar Ca2+and assessing its role in physiological and pathological functions. Here we review targeting strategies to express aequorins in various organelles. We address critical topics such as probe affinity tuning as well as normalization and calibration of the signal. We also focus on bioluminescent Ca2+imaging in nucleus or mitochondria of living cells. Finally, recent advances with a new chimeric GFP-aequorin protein (GAP), which can be used either as luminescent or fluorescent Ca2+probe, are presented. GAP is robustly expressed in transgenic flies and mice, where it has proven to be a suitable Ca2+indicator for monitoring physiological Ca2+signaling ex vivo and in vivo.
authors.affiliation: Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), c/Sanz y Forés 3, 47003 Valladolid, Spain. Electronic address: talonso@ibgm.uva.es.
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Alonso
authors.affiliation: Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), c/Sanz y Forés 3, 47003 Valladolid, Spain.
authors.forename: Macarena
authors.initials: M
authors.lastname: Rodríguez-Prados
authors.affiliation: Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), c/Sanz y Forés 3, 47003 Valladolid, Spain.
authors.forename: Paloma
authors.initials: P
authors.lastname: Navas-Navarro
authors.affiliation: Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), c/Sanz y Forés 3, 47003 Valladolid, Spain.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Rojo-Ruiz
authors.affiliation: Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid and Consejo Superior de Investigaciones Científicas (CSIC), c/Sanz y Forés 3, 47003 Valladolid, Spain. Electronic address: jgsancho@ibgm.uva.es.
authors.forename: Javier
authors.initials: J
authors.lastname: García-Sancho
mesh_terms: D000331:Aequorin / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism; D042541:Intracellular Space / Q000378:metabolism*; D015335:Molecular Probes / Q000378:metabolism*; D015388:Organelles / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D015335:Molecular Probes; D000331:Aequorin; D002118:Calcium
keywords: Aequorin; Calcium signaling; Endoplasmic reticulum; Golgi apparatus; Hippocampus; Intracellular organella; Skeletal muscle