title: Environmental signal integration by a modular AND gate.
abstract: Microorganisms use genetic circuits to integrate environmental information. We have constructed a synthetic AND gate in the bacterium Escherichia coli that integrates information from two promoters as inputs and activates a promoter output only when both input promoters are transcriptionally active. The integration occurs via an interaction between an mRNA and tRNA. The first promoter controls the transcription of a T7 RNA polymerase gene with two internal amber stop codons blocking translation. The second promoter controls the amber suppressor tRNA supD. When both components are transcribed, T7 RNA polymerase is synthesized and this in turn activates a T7 promoter. Because inputs and outputs are promoters, the design is modular; that is, it can be reconnected to integrate different input signals and the output can be used to drive different cellular responses. We demonstrate this modularity by wiring the gate to integrate natural promoters (responding to Mg(2+) and AI-1) and using it to implement a phenotypic output (invasion of mammalian cells). A mathematical model of the transfer function is derived and parameterized using experimental data.
authors: Department of Pharmaceutical Chemistry, QB3: California Institute for Quantitative Biological Research, The University of California San Francisco, San Francisco, CA 94158-2330, USA.
authors: J Christopher
authors: JC
authors: Anderson
authors: Christopher A
authors: CA
authors: Voigt
authors: Adam P
authors: AP
authors: Arkin
mesh_terms: D001089:Arabinose / Q000494:pharmacology; D017123:Bacteriophage T7 / Q000201:enzymology / Q000235:genetics*; D018389:Codon, Nonsense; D012321:DNA-Directed RNA Polymerases / Q000096:biosynthesis / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D015967:Gene Expression Regulation, Viral / Q000187:drug effects; D017930:Genes, Reporter; D016153:Genes, Suppressor; D005814:Genes, Viral / Q000187:drug effects; D005818:Genetic Engineering / Q000379:methods*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D008274:Magnesium / Q000494:pharmacology; D008957:Models, Genetic; D011401:Promoter Regions, Genetic / Q000187:drug effects; D014176:Protein Biosynthesis; D012329:RNA, Bacterial / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012343:RNA, Transfer / Q000235:genetics*; D012362:RNA, Transfer, Ser / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D012459:Salicylates / Q000494:pharmacology; D049490:Systems Biology; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D018389:Codon, Nonsense; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012362:RNA, Transfer, Ser; D012367:RNA, Viral; D012459:Salicylates; D014764:Viral Proteins; D049452:Green Fluorescent Proteins; D012343:RNA, Transfer; D001089:Arabinose; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases; D008274:Magnesium
references: Biotechnol Bioeng. 2004 Aug 20;87(4):478-84
references: 15286985
references: Nat Biotechnol. 2004 Jul;22(7):841-7
references: 15208640
references: J Bacteriol. 1970 Jul;103(1):32-6
references: 4912529
references: Cell. 1987 Aug 28;50(5):769-78
references: 3304658
references: Mol Microbiol. 1995 Sep;17(5):801-12
references: 8596430
references: Science. 1997 Sep 5;277(5331):1453-62
references: 9278503
references: J Bacteriol. 1999 Sep;181(17):5516-20
references: 10464230
references: Nature. 2005 Apr 28;434(7037):1130-4
references: 15858574
references: Nature. 2005 Nov 24;438(7067):449-53
references: 16306983
references: J Mol Biol. 2006 Jan 27;355(4):619-27
references: 16330045
references: J Theor Biol. 2006 Apr 21;239(4):417-34
references: 16171830
references: Cell. 2006 Apr 21;125(2):237-46
references: 16630813
references: Annu Rev Biophys Biomol Struct. 2006;35:225-49
references: 16689635
references: Mol Syst Biol. 2006;2:2006.0028
references: 16738572
references: Nucleic Acids Res. 2006 Jul 1;34(Web Server issue):W516-23
references: 16845061
references: Curr Opin Struct Biol. 2006 Aug;16(4):551-6
references: 16842994
references: Curr Opin Biotechnol. 2006 Oct;17(5):548-57
references: 16978856
references: Mol Biosyst. 2007 May;3(5):343-53
references: 17460793
references: Mol Plant Microbe Interact. 2000 Nov;13(11):1243-50
references: 11059491
references: Chem Biol. 2002 Feb;9(2):237-44
references: 11880038
references: Proc Natl Acad Sci U S A. 2002 May 14;99(10):7060-5
references: 11983857
references: Science. 2002 May 24;296(5572):1466-70
references: 12029133
references: Nat Biotechnol. 2002 Oct;20(10):1044-8
references: 12244330
references: Proc Natl Acad Sci U S A. 2002 Dec 24;99(26):16587-91
references: 12451174
references: J Bacteriol. 2003 Jul;185(13):3696-702
references: 12813061
references: Proc Natl Acad Sci U S A. 2003 Jun 24;100(13):7702-7
references: 12805558
references: Science. 2003 Sep 26;301(5641):1904-8
references: 14512628
references: Nature. 2004 Apr 22;428(6985):868-71
references: 15064770
references: Proc Natl Acad Sci U S A. 2004 Apr 27;101(17):6355-60
references: 15096621
references: Biophys J. 2004 Oct;87(4):2195-202
references: 15454422