title: Precise and reliable gene expression via standard transcription and translation initiation elements.
abstract: An inability to reliably predict quantitative behaviors for novel combinations of genetic elements limits the rational engineering of biological systems. We developed an expression cassette architecture for genetic elements controlling transcription and translation initiation in Escherichia coli: transcription elements encode a common mRNA start, and translation elements use an overlapping genetic motif found in many natural systems. We engineered libraries of constitutive and repressor-regulated promoters along with translation initiation elements following these definitions. We measured activity distributions for each library and selected elements that collectively resulted in expression across a 1,000-fold observed dynamic range. We studied all combinations of curated elements, demonstrating that arbitrary genes are reliably expressed to within twofold relative target expression windows with ∼93% reliability. We expect the genetic element definitions validated here can be collectively expanded to create collections of public-domain standard biological parts that support reliable forward engineering of gene expression at genome scales.
authors.affiliation: BIOFAB International Open Facility Advancing Biotechnology, Emeryville, California, USA.
authors.forename: Vivek K
authors.initials: VK
authors.lastname: Mutalik
authors.forename: Joao C
authors.initials: JC
authors.lastname: Guimaraes
authors.forename: Guillaume
authors.initials: G
authors.lastname: Cambray
authors.forename: Colin
authors.initials: C
authors.lastname: Lam
authors.forename: Marc Juul
authors.initials: MJ
authors.lastname: Christoffersen
authors.forename: Quynh-Anh
authors.initials: QA
authors.lastname: Mai
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Tran
authors.forename: Morgan
authors.initials: M
authors.lastname: Paull
authors.forename: Jay D
authors.initials: JD
authors.lastname: Keasling
authors.forename: Adam P
authors.initials: AP
authors.lastname: Arkin
authors.forename: Drew
authors.initials: D
authors.lastname: Endy
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D015723:Gene Library; D005818:Genetic Engineering; D016680:Genome, Bacterial; D039662:Prokaryotic Initiation Factors / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D039662:Prokaryotic Initiation Factors; D012329:RNA, Bacterial; D012333:RNA, Messenger