Dr Francisco Navarro

Francisco J. Navarro's work focuses on the function of small RNA (sRNA) molecules and their use as regulatory elements in synthetic gene circuits. sRNA molecules most likely evolved as a defense mechanism against viruses and retro-transposons, and were co-opted for fine-tuning of gene expression. Their small size and predictable targeting rules make them perfect tools for regulating gene expression in synthetic gene circuits. This project is carried out in the green alga Chlamydomonas reinhardtii, which is amenable to genetic manipulation and a model organism for key plant processes, such as photosynthesis. With an sRNA pathway that resembles that of higher plants, Chlamydomonas allows to test proof-of-principle small RNA-based genetic devices before extrapolating to other plant species.

Francisco did his PhD in the laboratory of Prof. Jose Manuel Siverio (University of La Laguna, Spain). He focused on the nitrate assimilation process of the methylotrophic yeast Hansenula polymorpha, which has important biotechnological applications, and characterized the posttranslational regulation of the main nitrate transporter. This was followed by a postdoc in the laboratory of Sir Paul Nurse, first at The Rockefeller University, USA, and then at London Research Institute, on cell size control and regulation of gene expression by RNA-binding proteins. Through a systematic screening of a gene deletion collection of the fission yeast Schizosaccharomyces pombe, he identified a set of novel genes involved in the coordination between cell growth and cell cycle progression.

Francisco’s research interests concern questions regarding global regulation of gene expression and limits of cell growth. These questions are relevant to synthetic biology because synthetic gene circuits are embedded into the cell’s own gene circuits, and so their activities are not insulated from global cell regulation. He thinks that microorganisms will continue to be useful research models to uncover new exciting biology, and contribute to the advance of synthetic biology. The fast growth and recently available range of tools and resources are making unicellular algae interesting chassis for synthetic biology, with potential industrial applications in the biopharming sector.

He is also a collaborator of Café Synthetique, an informal monthly meetup with public talks that brings together the Cambridge synthetic biology community. 

Dr Noam Chayut

I am interested in the interface between applied plant breeding and plant metabolism. In my master’s thesis we used classical breeding of passionfruit with the goal of releasing new varieties, now used by farmers. In my PhD thesis we studied carotenoid metabolism in melons and established a molecular marker now used routinely by melon breeders. More importantly, we suggested a novel non-transgenic path toward pro-vitamin A carotenoid biofortification of food crops. The objective of the current OpenPlant project is to develop pre-breeding lines of beetroot for the production of L-DOPA.  

L-DOPA is used to treat Parkinson’s symptoms; however, the current costs of chemical synthesis make it unavailable for deprived populations worldwide. In addition, there is a growing demand for ‘natural’ or plant sourced pharmaceutical substances in the first world. L- DOPA, a product of tyrosine hydroxylation, is an intermediate metabolite in biosynthesis of violet and yellow betalain pigments, in Beta vulgaris (table beet). L-DOPA natural steady state levels are very low, usually undetectable. We intend to block the turnover of L-Dopa in beetroot to allow its accumulation to levels that could enable low-tech accessible production in a plant system.

Current data indicate two betalain metabolic genes that, if repressed, may boost L-Dopa accumulation. Therefore, we aim to inhibit the activity of L-DOPA-dioxygenase, and L-DOPA-cyclase in beetroot. Currently, as proof of concept, we silence both genes in hairy roots system. We adopted three complementary strategies to meet the overarching objective of L-DOPA production in beet: a) Classical genetics; b) targeted genetic mutagenesis; and c) random mutagenesis. Yellow beet, mutated in L-DOPA-cyclase exists and can be crossed with “blotchy” red beet, which probably has lower L-DOPA-dioxygenase activity. Impairing L-DOPA-dioxygenase activity in yellow beet is carried out by both the targeted mutagenesis technology CRISPR/Cas9 and the random, yet more assured, EMS mutagenesis approach.

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Mr David Preston

I completed my Integrated Master’s in genetics at the University of Leeds, where I worked in Jϋrgen Denecke’s lab on synthetic receptors in the plant secretory pathway. In September 2016, I moved to the University Cambridge to start as an OpenPlant PhD student. I will do two lab rotations before beginning my PhD project.

For my first rotation, I worked in Jim Haseloff’s lab, which is developing advanced imaging tools for Marchantia polymorpha. My project involved characterising new enhancer trap lines in Marchantia. These lines will allow the discovery of regulatory elements involved in Marchantia development and aid in mapping enhancer activity onto computational models of the plant.

I am currently working in Alison Smith’s lab, attempting to import the Astaxanthin synthetic pathway into the chloroplast of the microalgae Chlamydomonas reinhardtii and studying mechanisms by which the ER and Chloroplast interact during biosynthetic pathways. Astaxanthin is a valuable terpene which is used both in industry and as a health supplement. Astaxanthin has been produced in several different organisms but not yet in Chlamydomonas, which has great potential for industrial biotechnology.

My primary interests are in making synthetic biology faster and cheaper. In future, I’d like to work on pathway optimization, rapid development of standard parts for synthetic biology and laboratory automation.