Interplay of degeneracy and non-degeneracy in fluctuations propagation in coherent feed-forward loop motif

Abstract

We present a stochastic framework to decipher fluctuations propagation in classes of coherent feed-forward loops. The systematic contribution of the direct (one-step) and indirect (two-step) pathways is considered to quantify fluctuations of the output node. We also consider both additive and multiplicative integration mechanisms of the two parallel pathways (one-step and two-step). Analytical expression of the output node's coefficient of variation shows contributions of intrinsic, one-step, two-step, and cross-interaction in closed form. We observe a diverse range of degeneracy and non-degeneracy in each of the decomposed fluctuations term and their contribution to the overall output fluctuations of each coherent feed-forward loop motif. Analysis of output fluctuations reveals a maximal level of fluctuations of the coherent feed-forward loop motif of type 1.

arXiv comment20 pages, 4 figures

References in corpus (9)

• Information flow and optimization in transcriptional control
• Signal detection, modularity and the correlation between extrinsic and intrinsic noise in biochemical networks
• Optimal signal processing in small stochastic biochemical networks
• The role of input noise in transcriptional regulation
• Exact results for noise power spectra in linear biochemical reaction networks
• Noise Characteristics of Feed Forward Loops
• The effect of feedback on the fidelity of information transmission of time-varying signals
• Role of relaxation time scale in noisy signal transduction
• The coherent feed-forward loop acts as an efficient information transmitting motif