title: Transplantability of a circadian clock to a noncircadian organism.
abstract: Circadian oscillators are posttranslationally regulated and affect gene expression in autotrophic cyanobacteria. Oscillations are controlled by phosphorylation of the KaiC protein, which is modulated by the KaiA and KaiB proteins. However, it remains unclear how time information is transmitted to transcriptional output. We show reconstruction of the KaiABC oscillator in the noncircadian bacteriumEscherichia coli. This orthogonal system shows circadian oscillations in KaiC phosphorylation and in a synthetic transcriptional reporter. Coexpression of KaiABC with additional native cyanobacterial components demonstrates a minimally sufficient set of proteins for transcriptional output from a native cyanobacterial promoter inE. coli. Together, these results demonstrate that a circadian oscillator is transplantable to a heterologous organism for reductive study as well as wide-ranging applications.
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA ; Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Anna H
authors.initials: AH
authors.lastname: Chen
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA ; Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: David
authors.initials: D
authors.lastname: Lubkowicz
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA ; Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Vivian
authors.initials: V
authors.lastname: Yeong
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA ; Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Roger L
authors.initials: RL
authors.lastname: Chang
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA ; Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Silver