Dataset Information

Chemodetection in fluctuating environments: receptor coupling, buffering, and antagonism.

ABSTRACT: Variability in the chemical composition of the extracellular environment can significantly degrade the ability of cells to detect rare cognate ligands. Using concepts from statistical detection theory, we formalize the generic problem of detection of small concentrations of ligands in a fluctuating background of biochemically similar ligands binding to the same receptors. We discover that in contrast with expectations arising from considerations of signal amplification, inhibitory interactions between receptors can improve detection performance in the presence of substantial environmental variability, providing an adaptive interpretation to the phenomenon of ligand antagonism. Our results suggest that the structure of signaling pathways responsible for chemodetection in fluctuating and heterogeneous environments might be optimized with respect to the statistics and dynamics of environmental composition. The developed formalism stresses the importance of characterizing nonspecific interactions to understand function in signaling pathways.

SUBMITTER: Lalanne JB

PROVIDER: S-EPMC4330740 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Chemodetection in fluctuating environments: receptor coupling, buffering, and antagonism.

Lalanne Jean-Benoît JB François Paul P

Proceedings of the National Academy of Sciences of the United States of America 20150126 6

Variability in the chemical composition of the extracellular environment can significantly degrade the ability of cells to detect rare cognate ligands. Using concepts from statistical detection theory, we formalize the generic problem of detection of small concentrations of ligands in a fluctuating background of biochemically similar ligands binding to the same receptors. We discover that in contrast with expectations arising from considerations of signal amplification, inhibitory interactions b ...[more]

PMID: 25624502

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Dataset Information

Chemodetection in fluctuating environments: receptor coupling, buffering, and antagonism.

Publications

Chemodetection in fluctuating environments: receptor coupling, buffering, and antagonism.

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