Figure 8: Microdomain analysis on the additive effect of and cAMP on CREB signaling in COS1 cells expressing the recombinant “atherosclerotic” channel. (A) FRET signal within the nucleus during selected time points during stimulation and cAMP application. Outlined are four types of signaling microdomains identified using 2D Mexican hat wavelet. Red circles represent stable microdomains that persist through both and cAMP application. White and yellow circles show microdomains stable activated by cAMP and , respectively. Green circles represent transient microdomains of CREB signaling activation. Axes show pixel numbers. (B) Typical appearances of the four types of CREB signaling microdomains activated by and/or cAMP application and recorded in their maximal development in relation to the time of applied stimuli. C: control recorded before stimulation. Color bars in (A) and (B) represent FRET values normalized to the maximum.