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arXiv · 0904.2676

Geometric Characteristics of Dynamic Correlations for Combinatorial Regulation in Gene Expression Noise

Jiajun Zhang·Zhanjiang Yuan·Tianshou Zhou
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Abstract

Knowing which mode of combinatorial regulation (typically, AND or OR logic operation) that a gene employs is important for determining its function in regulatory networks. Here, we introduce a dynamic cross-correlation function between the output of a gene and its upstream regulator concentrations for signatures of combinatorial regulation in gene expression noise. We find that the correlation function is always upwards convex for the AND operation whereas downwards convex for the OR operation, whichever sources of noise (intrinsic or extrinsic or both). In turn, this fact implies a means for inferring regulatory synergies from available experimental data. The extensions and applications are discussed.

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Jiajun Zhang, Zhanjiang Yuan, Tianshou Zhou. 2009-04-17. Geometric Characteristics of Dynamic Correlations for Combinatorial Regulation in Gene Expression Noise. https://doi.org/10.1103/physreve.80.021905

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