Figure 2. Spatial–temporal properties of... | Rockefeller University Press

Figure 2.

Spatial–temporal properties of Ca2+spark fluorescence (dF/Fo). The model cell dimensions were 5 × 5 × 100 μm. Solutions contained 30 μM Fluo-4, bath[Ca2+] = 100 nM, and LSR [Ca2+] = 0.6 mM, including the effects of blurring by a microscope with a point spread of 0.25 μm in x and z and 1 μm in y. (A) Individual sparks generated from dyads containing RyR2 clusters of either 11, 25, or 60 RyR2 listed along with frequency/dyad (Freq), amplitude (Amp), time from 10% to peak amplitude (TTP), full width at half maximum (FWHM), and full duration and half maximum (FDHM). (B) Simulated confocal z-t line scan of Ca2+ sparks where dyads contain an exponential distribution of RyR2 cluster sizes. Green circles indicate sparks detected with dF/Fo > 0.5. (C) Frequency of Ca2+ sparks detected and its dependence on [Ca2+] in the LSR. (D–G) Distribution of Ca2+ spark properties accumulated from 4 × 1-s simulated line scans. Refer to the image caption for details.

Spatial–temporal properties of Ca ²⁺ spark fluorescence (dF/Fo). The model cell dimensions were 5 × 5 × 100 μm. Solutions contained 30 μM Fluo-4, bath[Ca²⁺] = 100 nM, and LSR [Ca²⁺] = 0.6 mM, including the effects of blurring by a microscope with a point spread of 0.25 μm in x and z and 1 μm in y. (A) Individual sparks generated from dyads containing RyR2 clusters of either 11, 25, or 60 RyR2 listed along with frequency/dyad (Freq), amplitude (Amp), time from 10% to peak amplitude (TTP), full width at half maximum (FWHM), and full duration and half maximum (FDHM). (B) Simulated confocal z-t line scan of Ca²⁺ sparks where dyads contain an exponential distribution of RyR2 cluster sizes. Green circles indicate sparks detected with dF/Fo > 0.5. (C) Frequency of Ca²⁺ sparks detected and its dependence on [Ca²⁺] in the LSR. (D–G) Distribution of Ca²⁺ spark properties accumulated from 4 × 1-s simulated line scans.