Applications of FLIKA, a Python-based image processing and analysis platform, for studying local events of cellular calcium signaling.

The patterning of cytosolic Ca2+ signals underlies their ubiquitous ability to specifically regulate numerous cellular processes. Advances in fluorescence microscopy have made it possible to image these signals with unprecedented temporal and spatial resolution. However, this is a double-edged sword, as the resulting enormous data sets necessitate development of software to automate image processing and analysis. Here, we describe Flika, an open source, graphical user interface program written in the Python environment that contains a suite of built-in image processing tools to enable intuitive visualization of image data and analysis. We illustrate the utility and power of Flika by three applications for studying cellular Ca2+ signaling: a script for measuring single-cell global Ca2+ signals; a plugin for the detection, localization and analysis of subcellular Ca2+ puffs; and a script that implements a novel approach for fluctuation analysis of transient, local Ca2+ fluorescence signals. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.

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