posted on 2020-04-02, 19:16authored bySusanna Sauret-Güeto, Eftychios Frangedakis, Linda Silvestri, Marius Rebmann, Marta Tomaselli, Kasey Markel, Mihails Delmans, Anthony West, Nicola J. Patron, Jim Haseloff
We
present the OpenPlant toolkit, a set of interlinked resources
and techniques to develop Marchantia as testbed for bioengineering
in plants. Marchantia is a liverwort, a simple plant with an open
form of development that allows direct visualization of gene expression
and dynamics of cellular growth in living tissues. We describe new
techniques for simple and efficient axenic propagation and maintenance
of Marchantia lines with no requirement for glasshouse facilities.
Marchantia plants spontaneously produce clonal propagules within a
few weeks of regeneration, and lines can be amplified million-fold
in a single generation by induction of the sexual phase of growth,
crossing, and harvesting of progeny spores. The plant has a simple
morphology and genome with reduced gene redundancy, and the dominant
phase of its life cycle is haploid, making genetic analysis easier.
We have built robust Loop assembly vector systems for nuclear and
chloroplast transformation and genome editing. These have provided
the basis for building and testing a modular library of standardized
DNA elements with highly desirable properties. We have screened transcriptomic
data to identify a range of candidate genes, extracted putative promoter
sequences, and tested them in vivo to identify new
constitutive promoter elements. The resources have been combined into
a toolkit for plant bioengineering that is accessible for laboratories
without access to traditional facilities for plant biology research.
The toolkit is being made available under the terms of the OpenMTA
and will facilitate the establishment of common standards and the
use of this simple plant as testbed for synthetic biology.