Programming mRNA decay to modulate synthetic circuit resource allocation

Nat Commun. 2017 Apr 26:8:15128. doi: 10.1038/ncomms15128.

Abstract

Synthetic circuits embedded in host cells compete with cellular processes for limited intracellular resources. Here we show how funnelling of cellular resources, after global transcriptome degradation by the sequence-dependent endoribonuclease MazF, to a synthetic circuit can increase production. Target genes are protected from MazF activity by recoding the gene sequence to eliminate recognition sites, while preserving the amino acid sequence. The expression of a protected fluorescent reporter and flux of a high-value metabolite are significantly enhanced using this genome-scale control strategy. Proteomics measurements discover a host factor in need of protection to improve resource redistribution activity. A computational model demonstrates that the MazF mRNA-decay feedback loop enables proportional control of MazF in an optimal operating regime. Transcriptional profiling of MazF-induced cells elucidates the dynamic shifts in transcript abundance and discovers regulatory design elements. Altogether, our results suggest that manipulation of cellular resource allocation is a key control parameter for synthetic circuit design.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Endoribonucleases / genetics*
  • Endoribonucleases / metabolism
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics*
  • Escherichia coli Proteins / metabolism
  • Feedback, Physiological*
  • Metabolic Engineering / methods*
  • Metabolic Networks and Pathways
  • Models, Theoretical
  • Proteomics
  • RNA Stability / genetics*
  • RNA, Messenger / metabolism*
  • Regulatory Elements, Transcriptional

Substances

  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • MazF protein, E coli
  • RNA, Messenger
  • Endoribonucleases