title: Conditional control of mammalian gene expression by tetracycline-dependent hammerhead ribozymes.
abstract: Robust synthetic devices are requisite for the construction of synthetic genetic circuits and important scientific and technological tools to control cellular processes. We developed tetracycline-dependent ribozymes, which can switch on gene expression up to 8.7-fold upon addition of tetracycline. A tetracycline aptamer was grafted onto the hammerhead ribozyme in such a way that ligand binding to the aptamers destroys a loop-loop interaction within the ribozyme thereby inhibiting ribozyme cleavage and allowing gene expression. The advantage of the presented regulatory system is its independence of any regulatory proteins. The stable integration of the ribozyme into the genome of HeLa cells indicates a low background activity in the absence of ligand. Furthermore, the ligand concentration required to robustly flip the switch does not affect cell viability and therefore allows a long-term application of the system. These properties turn the tetracycline-dependent ribozymes into a very promising tool for conditional gene expression in mammalian cells.
authors.affiliation: †Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany.
authors.forename: Kim
authors.initials: K
authors.lastname: Beilstein
authors.affiliation: †Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Wittmann
authors.affiliation: ‡Institute for Tumor Biology and Experimental Therapy, Georg-Speyer-Haus, Paul-Ehrlich-Str. 42-44, D-60596 Frankfurt, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Grez
authors.affiliation: †Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany.
authors.forename: Beatrix
authors.initials: B
authors.lastname: Suess
mesh_terms: D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D015870:Gene Expression / Q000187:drug effects* / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008024:Ligands; D008322:Mammals; D009690:Nucleic Acid Conformation; D016337:RNA, Catalytic / Q000235:genetics*; D058928:Riboswitch / Q000187:drug effects / Q000235:genetics; D013752:Tetracycline / Q000494:pharmacology*
chemical_list: D008024:Ligands; D016337:RNA, Catalytic; D058928:Riboswitch; C427204:hammerhead ribozyme; D013752:Tetracycline
keywords: HeLa cells; aptamer; engineered riboswitch; ribozyme; synthetic biology; tetracycline