title: Design and construction of a versatile synthetic network for bistable gene expression in mammalian systems.
abstract: We constructed and modeled a novel synthetic network which may be able to exhibit bistable expression of a reporter gene in mammalian cells. This network is based on an aptamer-fused short-hairpin RNA (shRNA) directed against a single mRNA encoding both a EGFP reporter gene and the repressor tTR-KRAB, which, in turn, represses transcription of the shRNA. The activity of the shRNA can be controlled by an inducer molecule (theophylline) which prevents the aptamer-fused shRNA to be properly processed. Repression of the tTR-KRAB can be relieved by treatment with doxycyline. This reciprocal negative feed-back loop can exhibit a bistable response, as shown through the mathematical analysis performed here. Specifically, the network can be controlled to induce sustained expression of a shRNA, or the reporter gene, with a transient input of two different inducer molecules.
authors.affiliation: Department of Engineering Mathematics, University of Bristol, Bristol, United Kingdom.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Polynikis
authors.forename: Giulia
authors.initials: G
authors.lastname: Cuccato
authors.forename: Stefania
authors.initials: S
authors.lastname: Criscuolo
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Hogan
authors.forename: Mario
authors.initials: M
authors.lastname: Di Bernardo
authors.forename: Diego
authors.initials: D
authors.lastname: Di Bernardo
mesh_terms: D000818:Animals; D052157:Aptamers, Nucleotide / Q000235:genetics; D016466:CHO Cells; D019295:Computational Biology / Q000379:methods*; D006224:Cricetinae; D003412:Cricetulus; D004318:Doxycycline / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D053263:Gene Regulatory Networks / Q000187:drug effects; D057809:HEK293 Cells; D006801:Humans; D008322:Mammals / Q000235:genetics*; D008957:Models, Genetic; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D034741:RNA, Small Interfering; D004318:Doxycycline