2026-04-27T21:55:03Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/59572021-06-23T09:48:03Zcom_10324_1133com_10324_931com_10324_894col_10324_1209

Álvarez Martín, Javier Montero Zoccola, María Teresa Calcio - Metabolismo Producción Científica The photoprotein aequorin was the first probe used to measure specifically the [Ca2+] inside the lumen of the endoplasmic reticulum ([Ca2+]ER) of intact cells and it provides values for the steady-state [Ca2+]ER, around 500 M, that closely match those obtained now by other procedures. Aequorin-based methods to measure [Ca2+]ER offer several advantages: (i) targeting of the probe is extremely precise; (ii) the use of low Ca2+-affinity aequorin allows covering a large dynamic range of [Ca2+], from 10−5 to 10−3 M; (iii) aequorin is nearly insensitive to changes in Mg2+ or pH, has a high signal-to-noise ratio and calibration of the results in [Ca2+] is made straightforward using a simple algorithm; and (iv) the equipment required for luminescence measurements in cell populations is simple and low-cost. On the negative side, this technique has also some disadvantages: (i) the relatively low amount of emitted light makes difficult performing single-cell imaging studies; (ii) reconstitution of aequorin with coelenterazine requires previous complete depletion of Ca2+ of the ER for 1–2 h, a maneuver that may result in deleterious effects in some cells; (iii) because of the high rate of aequorin consumption at steady-state [Ca2+]ER, only relatively brief experiments can be performed; and (iv) expression of ER-targeted aequorin requires previous transfection or infection to introduce the appropriate DNA construct, or alternatively the use of stable cell clones. Choosing aequorin or other techniques to measure [Ca2+]ER will depend of the correct balance between these properties in a particular problem. 2014-09-15 2014-09-15 2002 info:eu-repo/semantics/article Cell Calcium, 2002, vol. 32, n. 5-6, p. 251-260 0143-4160 http://uvadoc.uva.es/handle/10324/5957 10.1016/S0143-4160(02)00186-0 251 5-6 260 Cell Calcium 32 eng info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Attribution-NonCommercial-NoDerivatives 4.0 International Elsevier Ltd.