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Merck

Ultrasensitive fluorescent proteins for imaging neuronal activity.

Nature (2013-07-23)
Tsai-Wen Chen, Trevor J Wardill, Yi Sun, Stefan R Pulver, Sabine L Renninger, Amy Baohan, Eric R Schreiter, Rex A Kerr, Michael B Orger, Vivek Jayaraman, Loren L Looger, Karel Svoboda, Douglas S Kim
ABSTRACT

Fluorescent calcium sensors are widely used to image neural activity. Using structure-based mutagenesis and neuron-based screening, we developed a family of ultrasensitive protein calcium sensors (GCaMP6) that outperformed other sensors in cultured neurons and in zebrafish, flies and mice in vivo. In layer 2/3 pyramidal neurons of the mouse visual cortex, GCaMP6 reliably detected single action potentials in neuronal somata and orientation-tuned synaptic calcium transients in individual dendritic spines. The orientation tuning of structurally persistent spines was largely stable over timescales of weeks. Orientation tuning averaged across spine populations predicted the tuning of their parent cell. Although the somata of GABAergic neurons showed little orientation tuning, their dendrites included highly tuned dendritic segments (5-40-µm long). GCaMP6 sensors thus provide new windows into the organization and dynamics of neural circuits over multiple spatial and temporal scales.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Calcium, SAJ first grade, ≥99.5%
Sigma-Aldrich
Calcium, dendritic pieces, purified by distillation, 99.99% trace metals basis
Sigma-Aldrich
Calcium, granular, 99%
Sigma-Aldrich
Calcium, pieces, <1 cm, 99%
Sigma-Aldrich
Calcium, turnings, 99% trace metals basis
Sigma-Aldrich
Calcium, dendritic pieces, purified by distillation, 99.9% trace metals basis