Sequestration shapes the response of signal transduction cascades

Molecular Neurobiology, Free University Berlin, and Institute for Theoretical Biology, Humboldt University Berlin, Berlin, Germany.
International Union of Biochemistry and Molecular Biology Life (Impact Factor: 3.14). 12/2006; 58(11):659-63. DOI: 10.1080/15216540600994340
Source: PubMed


Many signal transduction cascades are composed of covalent modification cycles such as kinase/phosphatase cycles. In the 1980s Goldbeter and Koshland showed that such cycles can exhibit non-linear input-output relations when the enzymes are saturated by their substrates, which may facilitate signal processing. Recent papers show that this mechanism is unlikely to cause non-linearity in mammalian signal transduction cascades as sequestration of the target due to enzyme concentrations present in these cascades will hamper this mechanism. However, sequestration due to high-affinity enzymes can shape the dynamics and steady-state behaviour of signal transduction cascades in different ways, some of which are discussed in this review.

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