G protein-coupled receptor-mediated calcium signaling in astrocytes

Maurizio De Pittà; Eshel Ben-Jacob; Hugues Berry

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arXiv · 1801.06606

G protein-coupled receptor-mediated calcium signaling in astrocytes

Maurizio De Pittà·Eshel Ben-Jacob·Hugues Berry

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Abstract

Astrocytes express a large variety of G~protein-coupled receptors (GPCRs) which mediate the transduction of extracellular signals into intracellular calcium responses. This transduction is provided by a complex network of biochemical reactions which mobilizes a wealth of possible calcium-mobilizing second messenger molecules. Inositol 1,4,5-trisphosphate is probably the best known of these molecules whose enzymes for its production and degradation are nonetheless calcium-dependent. We present a biophysical modeling approach based on the assumption of Michaelis-Menten enzyme kinetics, to effectively describe GPCR-mediated astrocytic calcium signals. Our model is then used to study different mechanisms at play in stimulus encoding by shape and frequency of calcium oscillations in astrocytes.

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Maurizio De Pittà, Eshel Ben-Jacob, Hugues Berry. 2018-01-20. G protein-coupled receptor-mediated calcium signaling in astrocytes. https://arxiv.org/abs/1801.06606

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