Advantage and Core Benefit
- Obtains desired protein faster than conventional techniques such as magnICON
- Protein expression is increased by suppressing necrosis by spraying with ascorbic acid.
- Applicable to Solanaceae, Asteraceae, Cucurbitaceae, and Leguminosae, and expected to be applied to genome editing and production of useful metabolites.
Background and Technology
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Protein production in plants is expected to be advantageous in terms of running cost, but one of the challenges is that the expression level is lower than that of E. coli etc.
As a method of protein production in plants, the agroinfiltration method has been developed to transiently express target proteins by Agrobacterium infection. The amount of protein expression in the agroinfiltration method depends on the vector that carries the gene from the bacterium to the plant cell.
The inventors have succeeded in expressing large amounts of protein by modifying the vector in a system that infects Nicotiana benthamiana. By incorporating a Geminivirus replication system in the vector and including a double terminator, the mRNA encoding the target gene was transcribed in large quantities, resulting in an expression level of approximately 4 mg of protein per gram fresh weight (FW). This amount of protein expression is comparable to that of expression systems such as E. coli. Compared to magnICON, an existing plant expression system, it has an advantage in terms of rapid production.
In addition, protein expression is now possible not only in N. benthamiana but also in various other plants such as lettuce, eggplant, tomato, soybean, and melon, and can be used for genome editing in each of these plants.
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Examples of Application
- Expression of proteins and complexes that are difficult to express in coli and other bacteria
Human Cullin protein, antibody formation (https://doi.org/10.5511/plantbiotechnology.21.0610a) - Production of pharmaceutical-related proteins
Birch pollen allergen Bet v 1 binding to IgE in allergic patients (https://doi.org/10.3389/fpls.2020.00344)
Recombinant lactoferrin production (https://doi.org/10.5511/plantbiotechnology.23.0128a) - Substance production by biosynthetic enzyme expression
4DO (4-deoxyrobanchol) accumulation (2.1 mg/g FW) by expression of large amounts of metabolic enzymes; D27, CCD7, CCD8, CYP711A2. (https://doi.org/10.3389/fpls.2022.1027004)
Patent
Basic patent: JP6850041B, CA3059025C (Granted) US2021-0108218, EP3604546(Pending)
Improved invention: CA3144718C (Granted), JP2021-020421, US2022-0256847, EP4008723(Pending)
Application patent (genome editing): Pending in Japan
Researcher
Dr. Kenji Miura (University of Tsukuba)
Expectations
We are looking for companies that are interested in licensing the patents related to our invention, a system for high protein production in plants, to work on protein production in plants, production of secondary metaboloites, and generation of genome-edited crops. Licenses for research and development purposes are also available. We can also provide a paid MTA of the vector (pBYR2HS, pTKB3) for evaluation studies.
Project.WL-04918