Genetically encoded Ca2+ indicators: Properties and evaluation

Abstract

Genetically encoded calcium ion (Ca(2+)) indicators have become very useful and widely used tools for Ca(2+) imaging, not only in cellular models, but also in living organisms. However, the in vivo and in situ characterization of these indicators is tedious and time consuming, and it does not provide information regarding the suitability of an indicator for particular experimental environments. Thus, initial in vitro evaluation of these tools is typically performed to determine their properties. In this review, we examined the properties of dynamic range, affinity, selectivity, and kinetics for Ca(2+) indicators. Commonly used strategies for evaluating these properties are presented. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.

Live Cell Imaging with R-GECO1 Sheds Light on flg22- and Chitin-Induced Transient [Ca 2+ ] cyt Patterns in Arabidopsis

“…Genetically encoded indicators (GECIs) are ideal tools to study transient [Ca 2+ ] cyt patterns, as they enable non-invasive monitoring of [Ca 2+ ] cyt dynamics in living cells (Monshausen, 2012; Pérez Koldenkova and Nagai, 2013). In plants, luminescent aequorin-based Ca 2+ reporters have been widely used to investigate the role of Ca 2+ signaling during abiotic stress responses, such as cold, osmotic, and salt stress (Knight et al, 1991, 1996; Kiegle et al, 2000; Martí et al, 2013), and to study Ca 2+ signaling during plant defense reactions (Blume et al, 2000; Lecourieux et al, 2002; Kwaaitaal et al, 2011; Ranf et al, 2011).…”

Fast gene transfer into the adult zebrafish brain by herpes simplex virus 1 (HSV-1) and electroporation: methods and optogenetic applications

“…These vectors allow for the rapid expression of transgenes in spatially defined brain areas and can be targeted to defined subsets of cells by specific promoters and intersectional genetic approaches. As a consequence, viral gene transfer has become an important tool for a wide range of applications including optical measurements and manipulations of neuronal activity using genetically encoded calcium indicators (GECIs) and optogenetic probes, respectively (Knöpfel et al, 2010; Yizhar et al, 2011; Pérez Koldenkova and Nagai, 2013). In zebrafish, however, commonly used AAVs or lentiviruses failed to produce detectable expression of transgenes in the brain (Zhu et al, 2009).…”

Genetically Encoded Ca 2+ Indicators in Cardiac Myocytes

“…There are numerous reviews on GECI in general, [57][58][59][60][61][62] and a broad subset of sensors has also been applied in cardiac investigations, which are summarized in Figure 2. The left 4 columns in Figure 2 provide the basic properties of the sensors, including a scheme for the principle of operation.…”