Workpackage C: New mechanisms for regulation of gene expression
RNA-based mechanisms for gene regulation complement conventional transcriptional regulation, and can be highly flexible and modular. These mechanisms are common in nature, and are only now being harnessed for synthetic systems.
OpenPlant aims to expand the availability of genetic regulatory elements across a range of plants, algae and cyanobacteria. Work is ongoing and projects on riboswitches, riboregulator circuits, cyanobacteria circuits and circadian rhythm regulators will start during 2017.
Tools for gene expression control using the endogenous RNA silencing machinery of the green alga Chlamydomonas reinhardtii have been developed by Francisco Navarro (Baulcombe Lab).
This has increased the number of available DNA parts in the developing Chlamydomonas MoClo Kit, which allows fast and efficient construction of DNA based on modular assembly. miRNA precursors have been assessed for impact on the expression of the cassette using an easy and fast reporter system based on the endogenous gene (MAA7). This confers resistance to the metabolic drug 5-fluoroindole when repressed and used in combination with fluorescent proteins optimized for expression in Chlamydomonas as reporters of gene expression and silencing, has allowed measurement of miRNA function at both population and single cell level.
Francisco Navarro is now setting up and characterising a simple circuit in Chlamydomonas in which both miRNA and target molecule are produced from synthetic DNA constructs. This will be used to characterize the kinetics and key parameters of the basic unit of the miRNA-dependent gene silencing, including targeting rules of miRNAs in Chlamydomonas.