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Combinatorics of feedback in cellular uptake and metabolism of small molecules.

ABSTRACT: We analyze the connection between structure and function for regulatory motifs associated with cellular uptake and usage of small molecules. Based on the boolean logic of the feedback we suggest four classes: the socialist, consumer, fashion, and collector motifs. We find that the socialist motif is good for homeostasis of a useful but potentially poisonous molecule, whereas the consumer motif is optimal for nutrition molecules. Accordingly, examples of these motifs are found in, respectively, the iron homeostasis system in various organisms and in the uptake of sugar molecules in bacteria. The remaining two motifs have no obvious analogs in small molecule regulation, but we illustrate their behavior using analogies to fashion and obesity. These extreme motifs could inspire construction of synthetic systems that exhibit bistable, history-dependent states, and homeostasis of flux (rather than concentration).

SUBMITTER: Krishna S

PROVIDER: S-EPMC2409224 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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Combinatorics of feedback in cellular uptake and metabolism of small molecules.

Krishna Sandeep S Semsey Szabolcs S Sneppen Kim K

Proceedings of the National Academy of Sciences of the United States of America 20071219 52

We analyze the connection between structure and function for regulatory motifs associated with cellular uptake and usage of small molecules. Based on the boolean logic of the feedback we suggest four classes: the socialist, consumer, fashion, and collector motifs. We find that the socialist motif is good for homeostasis of a useful but potentially poisonous molecule, whereas the consumer motif is optimal for nutrition molecules. Accordingly, examples of these motifs are found in, respectively, t ...[more]

PMID: 18093927

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