From qualitative to quantitative: the state of the art and challenges for plant synthetic biology

Abstract

Backgrounds: As an increasing number of synthetic switches and circuits have been created for plant systems and of synthetic products produced in plant chassis, plant synthetic biology is taking a strong foothold in agriculture and medicine. The ever-exploding data has also promoted the expansion of toolkits in this field. Genetic parts libraries and quantitative characterization approaches have been developed. However, plant synthetic biology is still in its infancy. The considerations for selecting biological parts to design and construct genetic circuits with predictable functions remain desired.

Results: In this article, we review the current biotechnological progresses in field of plant synthetic biology. Assembly standardization and quantitative approaches of genetic parts and genetic circuits are discussed. We also highlight the main challenges in the iterative cycles of design-build-test-learn for introducing novel traits into plants.

Conclusion: Plant synthetic biology promises to provide important solutions to many issues in agricultural production, human health care, and environmental sustainability. However, tremendous challenges exist in this field. For example, the quantitative characterization of genetic parts is limited; the orthogonality and the transfer functions of circuits are unpredictable; and also, the mathematical modeling-assisted circuits design still needs to improve predictability and reliability. These challenges are expected to be resolved in the near future as interests in this field are intensifying.

Author summary

The flourishing plant science promotes the exploding number of data and the expansion of toolkits. Plant synthetic biology is still in its early stages and requires more quantitative and predictable study. Despite the challenges, some pioneering examples have been successfully demonstrated in model plants.

Graphical abstract

Keywords

plant synthetic biology / quantitative characterization / genetic parts / genetic circuits

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ACKNOWLEDGEMENTS

This work was supported by the National Key Research and Development Program of China (No. 2018YFA0900600), the Strategic Priority Research Program “Molecular mechanism of Plant Growth and Development” of Chinese Academy of Science (No. XDB27020202), the National Natural Science Foundation of China (Nos. 22077129, 32070328 and 41876084), the Natural Science Foundation of Shanghai Municipal Science and Technology Committee (No. 21ZR1470900), the Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project (No. TSBICIP-KJGG-002-15), the Program of Shanghai Academic Research Leader (No. 20XD1404400). This work was also financially supported by the Construction of the Registry and Database of Bioparts for Synthetic Biology of the Chinese Academy of Science (No. ZSYS-016), the International Partnership Program of Chinese Academy of Science (No. 153D31KYSB20170121), and the National Key Laboratory of Plant Molecular Genetics, SIPPE, Chinese Academy of Science.

COMPLIANCE WITH ETHICS GUIDELINES

Conflicts of interest The authors Chenfei Tian, Jianhua Li, and Yong Wang declare that they have no conflict of interests.

This article is a review and does not contain any human or animal subjects performed by any of the authors.

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