Simultaneous manipulation of source and sink metabolism for improved crop yield
Final Report Abstract
In this project, we implemented a metabolic engineering strategy of unprecedented scale in plants with the aim of demonstrating the most effective way to increase the yield of the harvested organs of crops. We used tomato as a test species but the results of this study will also be relevant for other crops. We introduced transgenes designed to engineer both source and sink tissues targeting multiple metabolic and transport processes in each in an attempt to remove flux bottlenecks from across the metabolic network. The objective was to increase the flow of both carbon and nitrogen to the sink organs. The project exploited the new technique of biolistic combinatorial co-transformation which allows the stable integration of a large number of transgenes into a single locus in any plant amenable to biolistic transformation of the nuclear genome. Based on prior knowledge, we have identified 20 transgene targets which have been introduced into tomato plants. A library of 75 transgenic lines has been generated and screening of these lines for transgene complement and fruit yield is underway. In addition, we have identified a number of novel gene targets for engineering increased C and N flow to the fruit from analysis of computational models of the tomato metabolic network and via an unbiased genetic screen using a backcrossed introgression lines population. These candidate genes, as well as some additional target amino acids transporters from our previous work, are being tested in transgenic plants. Ultimately, the most effective of these transgenes will be super-transformed into the highest yielding plants from the primary transgenic library.
Publications
- (2017), Engineering central metabolism – a grand challenge for plant biologists. Plant J, 90: 749–763
Sweetlove, L. J., Nielsen, J. and Fernie, A. R.
(See online at https://doi.org/10.1111/tpj.13464) - (2018) Computational analysis of the productivity-potential of CAM. Nature Plants 4: 165-171
Shameer, S., Baghalian, K., Cheung, C.Y.M., Ratcliffe, R.G. and Sweetlove, L.J.
(See online at https://doi.org/10.1038/s41477-018-0112-2) - (2018) Next-generation strategies for understanding and influencing source-sink relations in crop plants. Curr Opin Plant Biol.43:63-70
Sonnewald U, Fernie AR
(See online at https://doi.org/10.1016/j.pbi.2018.01.004) - (2018) The genetic architecture of photosynthesis and plant growth-related traits in tomato. Plant Cell Environ 41:327-341
de Oliveira Silva FM, Lichtenstein G, Alseekh S, Rosado-Souza L, Conte M, Suguiyama VF, Lira BS, Fanourakis D, Usadel B, Bhering LL, DaMatta FM, Sulpice R, Araújo WL, Rossi M, de Setta N, Fernie AR, Carrari F, Nunes-Nesi A
(See online at https://doi.org/10.1111/pce.13084) - (2018). Plastid transformation and its application in metabolic engineering. Curr. Op. Biotechnol., 49, 10-15
Fuentes, P., Armarego-Mariott, T. and Bock, R.
(See online at https://doi.org/10.1016/j.copbio.2017.07.004) - (2019) Leaf energy balance requires mitochondrial respiration and export of chloroplast NADPH in the light. Plant Physiol pp.00624.2019
Shameer, S., Ratcliffe, R.G. and Sweetlove, L.J.
(See online at https://doi.org/10.1104/pp.19.00624) - (2019). Recent advances and current challenges in synthetic biology of the plastid genetic system and metabolism. Plant Physiol., 179, 794-802
Boehm, C. R. and Bock, R.
(See online at https://doi.org/10.1104/pp.18.00767)
