Studying Calcium Signal Reshaping by Buffers Observing the Competition of Two Dyes

PIEGARI, ESTEFANIA; LOPEZ, LUCÍA; PONCE DAWSON, SILVINA

San Diego, CA

Congreso; Biophysical Society 56th Annual Meeting; 2012

Ca2þ signaling is ubiquitous across cell types. Ca2þ liberation through inositol 1,4,5-trisphosphate receptors (IP3Rs) is a key component of the Ca2þ signaling toolkit. The specificity and universality of intracellular cal- cium signals rely on the variety of spatio-temporal patterns that the concen- tration of this ion can display. It has been observed by I. Parker and collaborators that buffers can shape these patterns in different ways depend- ing on their kinetics. In this work we study how these different effects may arise by observing IP3R-mediated Ca2þ signals using two dyes simulta- neously. To this end we use a multi-spectral confocal microscope and two dyes (Fluo4 and Rhod2) that differ in their binding kinetics and emis- sion spectra. In this way we are able to study the competition between the two dyes probing the effect of their different kinetics on the observed signals.