title: A split intein T7 RNA polymerase for transcriptional AND-logic.
abstract: Synthetic biology has developed numerous parts for building synthetic gene circuits. However, few parts have been described for prokaryotes to integrate two signals at a promoter in an AND fashion, i.e. the promoter is only activated in the presence of both signals. Here we present a new part for this function: a split intein T7 RNA polymerase. We divide T7 RNA polymerase into two expression domains and fuse each to a split intein. Only when both domains are expressed does the split intein mediate protein trans-splicing, yielding a full-length T7 RNA polymerase that can transcribe genes via a T7 promoter. We demonstrate an AND gate with the new part: the signal-to-background ratio is very high, resulting in an almost digital signal. This has utility for more complex circuits and so we construct a band-pass filter in Escherichia coli. The split intein approach should be widely applicable for engineering artificial gene circuit parts.
authors.affiliation: EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain yolanda.schaerli@ieu.uzh.ch.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Schaerli
authors.affiliation: EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain.
authors.forename: Magüi
authors.initials: M
authors.lastname: Gili
authors.affiliation: EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Isalan
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D047668:Inteins; D008969:Molecular Sequence Data; D020040:Trans-Splicing; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D014764:Viral Proteins; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases