Comment on “Load-Induced Modulation of Signal Transduction Networks”: Reconciling Ultrasensitivity with Bifunctionality?

Sci. Signal., 3 January 2012
Vol. 5, Issue 205, p. lc1
DOI: 10.1126/scisignal.2002699

Comment on “Load-Induced Modulation of Signal Transduction Networks”: Reconciling Ultrasensitivity with Bifunctionality?

  1. Ronny Straube*
  1. Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany.
  1. *E-mail, rstraube{at}mpi-magdeburg.mpg.de; telephone, 0049-391-6110-481

Abstract

Jiang et al. (Research Article, 11 October 2011, DOI: 10.1126/scisignal.2002152) used a combined experimental and computational modeling approach to study the dynamic response behavior of covalent modification cycles in the presence of downstream targets (“loads”). Despite remarkable agreement between experiments and model predictions, there exists an apparent discrepancy in their approach because the utilized theoretical model does not reflect the bifunctional nature of the enzyme system used in experiments. Furthermore, a simple extension of the model to the case of bifunctional enzymes yields predictions that are partially at variance with the experimental results. It seems that an appropriate mechanistic model would have to reconcile two apparent contradictory concepts: ultrasensitivity and bifunctionality.

Citation:

R. Straube, Comment on “Load-Induced Modulation of Signal Transduction Networks”: Reconciling Ultrasensitivity with Bifunctionality?. Sci. Signal. 5, lc1 (2012).

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Response to Comment on "'Load-Induced Modulation of Signal Transduction Networks': Reconciling Ultrasensitivity with Bifunctionality?"
P. Jiang, A. C. Ventura, E. D. Sontag, S. D. Merajver, A. J. Ninfa, and D. Del Vecchio
Sci Signal 5, lc2-lc2 (3 January 2012)

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