Evolvability and hierarchy in rewired bacterial gene networks

Article

关键词: ESCHERICHIA-COLI;    REGULATORY NETWORK;    TRANSCRIPTIONAL REGULATION;    OPERON ORGANIZATION;    BIOFILM FORMATION;    GROWTH;    EXPRESSION;    TOLERANCE;    RPOS;    PHENOTYPES;   

DOI  :  10.1038/nature06847

来源: SCIE

【 摘 要 】

Sequencing DNA from several organisms has revealed that duplication and drift of existing genes have primarily moulded the contents of a given genome. Though the effect of knocking out or overexpressing a particular gene has been studied in many organisms, no study has systematically explored the effect of adding new links in a biological network. To explore network evolvability, we constructed 598 recombinations of promoters ( including regulatory regions) with different transcription or sigma-factor genes in Escherichia coli, added over a wild- type genetic background. Here we show that similar to 95% of new networks are tolerated by the bacteria, that very few alter growth, and that expression level correlates with factor position in the wild- type network hierarchy. Most importantly, we find that certain networks consistently survive over the wild type under various selection pressures. Therefore new links in the network are rarely a barrier for evolution and can even confer a fitness advantage.

【 授权许可】

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