Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments
Ca2+ release into the cytosol through inositol 1,4,5-trisphosphate receptors (IP3Rs) plays a relevant role in numerous physiological processes. IP3R-mediated Ca2+ signals involve Ca2+-induced Ca2+-release (CICR) whereby Ca2+ release through one open IP3R induces the opening of other channels. IP3Rs...
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19326203_v9_n4_p_Piegari http://hdl.handle.net/20.500.12110/paper_19326203_v9_n4_p_Piegari |
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paper:paper_19326203_v9_n4_p_Piegari2023-06-08T16:31:22Z Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments Ponce Dawson, Silvina calcium calcium fluorescent dye fused heterocyclic rings rhod-2 animal cell article calcium current calcium signaling controlled study female fluorescence analysis fluorescence imaging image analysis mathematical model molecular imaging nonhuman quantitative analysis signal noise ratio animal fluorescence imaging image processing metabolism procedures Xenopus laevis Animals Calcium Fluorescent Dyes Heterocyclic Compounds, 3-Ring Image Processing, Computer-Assisted Optical Imaging Signal-To-Noise Ratio Xenopus laevis Ca2+ release into the cytosol through inositol 1,4,5-trisphosphate receptors (IP3Rs) plays a relevant role in numerous physiological processes. IP3R-mediated Ca2+ signals involve Ca2+-induced Ca2+-release (CICR) whereby Ca2+ release through one open IP3R induces the opening of other channels. IP3Rs are apparently organized in clusters. The signals can remain localized (i.e., Ca2+ puffs) if CICR is limited to one cluster or become waves that propagate between clusters. Ca2+ puffs are the building blocks of Ca2+ waves. Thus, there is great interest in determining puff properties, especially in view of the current controversy on the spatial distribution of activatable IP3Rs. Ca 2+ puffs have been observed in intact cells with optical techniques proving that they are intrinsically stochastic. Obtaining a correct picture of their dynamics then entails being able to detect the whole range of puff sizes. Ca2+ puffs are observed using visible single-wavelength Ca 2+ dyes, slow exogenous buffers (e.g., EGTA) to disrupt inter-cluster CICR and UV-photolyzable caged IP3. Single-wavelength dyes increase their fluorescence upon calcium binding producing images that are strongly dependent on their kinetic, transport and photophysical properties. Determining the artifacts that the imaging setting introduces is particularly relevant when trying to analyze the smallest Ca2+ signals. In this paper we introduce a method to estimate the expected signal-to-noise ratio of Ca 2+ imaging experiments that use single-wavelength dyes. The method is based on the Number and Brightness technique. It involves the performance of a series of experiments and their subsequent analysis in terms of a fluorescence fluctuation model with which the model parameters are quantified. Using the model, the expected signal-to-noise ratio is then computed. Equivalence classes between different experimental conditions that produce images with similar signal-tonoise ratios can then be established. The method may also be used to estimate the smallest signals that can reliably be observed with each setting. © 2014 Piegari et al. Fil:Ponce Dawson, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2014 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19326203_v9_n4_p_Piegari http://hdl.handle.net/20.500.12110/paper_19326203_v9_n4_p_Piegari |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
calcium calcium fluorescent dye fused heterocyclic rings rhod-2 animal cell article calcium current calcium signaling controlled study female fluorescence analysis fluorescence imaging image analysis mathematical model molecular imaging nonhuman quantitative analysis signal noise ratio animal fluorescence imaging image processing metabolism procedures Xenopus laevis Animals Calcium Fluorescent Dyes Heterocyclic Compounds, 3-Ring Image Processing, Computer-Assisted Optical Imaging Signal-To-Noise Ratio Xenopus laevis |
| spellingShingle |
calcium calcium fluorescent dye fused heterocyclic rings rhod-2 animal cell article calcium current calcium signaling controlled study female fluorescence analysis fluorescence imaging image analysis mathematical model molecular imaging nonhuman quantitative analysis signal noise ratio animal fluorescence imaging image processing metabolism procedures Xenopus laevis Animals Calcium Fluorescent Dyes Heterocyclic Compounds, 3-Ring Image Processing, Computer-Assisted Optical Imaging Signal-To-Noise Ratio Xenopus laevis Ponce Dawson, Silvina Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| topic_facet |
calcium calcium fluorescent dye fused heterocyclic rings rhod-2 animal cell article calcium current calcium signaling controlled study female fluorescence analysis fluorescence imaging image analysis mathematical model molecular imaging nonhuman quantitative analysis signal noise ratio animal fluorescence imaging image processing metabolism procedures Xenopus laevis Animals Calcium Fluorescent Dyes Heterocyclic Compounds, 3-Ring Image Processing, Computer-Assisted Optical Imaging Signal-To-Noise Ratio Xenopus laevis |
| description |
Ca2+ release into the cytosol through inositol 1,4,5-trisphosphate receptors (IP3Rs) plays a relevant role in numerous physiological processes. IP3R-mediated Ca2+ signals involve Ca2+-induced Ca2+-release (CICR) whereby Ca2+ release through one open IP3R induces the opening of other channels. IP3Rs are apparently organized in clusters. The signals can remain localized (i.e., Ca2+ puffs) if CICR is limited to one cluster or become waves that propagate between clusters. Ca2+ puffs are the building blocks of Ca2+ waves. Thus, there is great interest in determining puff properties, especially in view of the current controversy on the spatial distribution of activatable IP3Rs. Ca 2+ puffs have been observed in intact cells with optical techniques proving that they are intrinsically stochastic. Obtaining a correct picture of their dynamics then entails being able to detect the whole range of puff sizes. Ca2+ puffs are observed using visible single-wavelength Ca 2+ dyes, slow exogenous buffers (e.g., EGTA) to disrupt inter-cluster CICR and UV-photolyzable caged IP3. Single-wavelength dyes increase their fluorescence upon calcium binding producing images that are strongly dependent on their kinetic, transport and photophysical properties. Determining the artifacts that the imaging setting introduces is particularly relevant when trying to analyze the smallest Ca2+ signals. In this paper we introduce a method to estimate the expected signal-to-noise ratio of Ca 2+ imaging experiments that use single-wavelength dyes. The method is based on the Number and Brightness technique. It involves the performance of a series of experiments and their subsequent analysis in terms of a fluorescence fluctuation model with which the model parameters are quantified. Using the model, the expected signal-to-noise ratio is then computed. Equivalence classes between different experimental conditions that produce images with similar signal-tonoise ratios can then be established. The method may also be used to estimate the smallest signals that can reliably be observed with each setting. © 2014 Piegari et al. |
| author |
Ponce Dawson, Silvina |
| author_facet |
Ponce Dawson, Silvina |
| author_sort |
Ponce Dawson, Silvina |
| title |
Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| title_short |
Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| title_full |
Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| title_fullStr |
Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| title_full_unstemmed |
Fluorescence fluctuations and equivalence classes of Ca2+ imaging experiments |
| title_sort |
fluorescence fluctuations and equivalence classes of ca2+ imaging experiments |
| publishDate |
2014 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19326203_v9_n4_p_Piegari http://hdl.handle.net/20.500.12110/paper_19326203_v9_n4_p_Piegari |
| work_keys_str_mv |
AT poncedawsonsilvina fluorescencefluctuationsandequivalenceclassesofca2imagingexperiments |
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1768541819499446272 |