Source: BENSON HILL BIOSYSTEMS, INC. submitted to NRP
NOVEL APPROACHES TO IMPROVE MAIZE YIELD
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SMALL BUSINESS GRANT
Reporting Frequency
Annual
Accession No.
1015825
Grant No.
2018-33610-28956
Cumulative Award Amt.
$99,784.00
Proposal No.
2018-00310
Multistate No.
(N/A)
Project Start Date
Sep 1, 2018
Project End Date
Apr 8, 2020
Grant Year
2018
Program Code
[8.2]- Plant Production and Protection-Biology
Recipient Organization
BENSON HILL BIOSYSTEMS, INC.
440 WEYCROFT GRANT DR
CARY,NC 275190849
Performing Department
(N/A)
Non Technical Summary
High-temperature stress can result in significant yield loss in maize, particularly when the stress coincides with reproductive growth stages and grain fill. Engineering of the starch biosynthetic pathway has been prioritized as an attempt to mitigate heat stress-induced yield losses. Traditional transgenic approaches to solve this problem are complicated by the presence of the native gene encoding the wild-type versions of the genes in this pathway. Recently developed genome editing approaches offer the opportunity to replace the native coding sequence with a gene encoding the more desirable version, resulting in maize plants that express only the improved gene version. Benson Hill Biosystems has develop a novel set of genome editing tools that can be used for this purpose.Application of these genome editing approaches to generate maize lines with thermostable enzymes is expected to produce maize lines with elevated yield, particularly when grown under challenging high-temperature conditions that are expected to occur with increasing frequency as a result of climate change. Successful demonstration of these technologies during this project represents a significant market opportunity for Benson Hill Biosystems.
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
20315101040100%
Knowledge Area
203 - Plant Biological Efficiency and Abiotic Stresses Affecting Plants;

Subject Of Investigation
1510 - Corn;

Field Of Science
1040 - Molecular biology;
Goals / Objectives
1) Demonstrate novel genome editing tools in a high value crop2) Generate targeted modifications to the maize genome to create a more sustainable crop system3) Regenerate maize events with the modifications in goal #2
Project Methods
A gene involved in starch biosythesis has been identified with thermal stability issues. Mutations to this gene have been identified which will increase thermal stability and overall activity. Maize lines will be transformed with genome editing reagents (nuclease, guide RNA, and repair template). Multiple versions of these reagents will be screened for activity and efficacy via molecular biology and next-generation sequencing. The best set of reagents will be used to develop edited lines of maize through an established transformation system. The resulting maize lines will be analyzed via molecular biology techniques to confirm the mutation.

Progress 09/01/18 to 04/30/20

Outputs
Target Audience: Nothing Reported Changes/Problems:The major problem encountered was that HDR-mediated genome edited maize events were not recovered. As such, the intended outputs of the project were not able to be pursued as initially envisioned. What opportunities for training and professional development has the project provided?The project offered opportunities for molecular biology and plant transformation personnel to design and test guide RNAs intended for editing of a high-value trait gene, and to explore the experimental parameters that could contribute to HDR-mediated editing as opposed to the more common NHEJ-mediated editing. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Multiple guide RNAs were screened for genome editing activity in the maize gene that was the target of these experiments. HDR experiments were performed but no HDR-mediated genome editing events were recovered unfortunately. As such goal #3 could not be pursued as envisioned.

Publications


    Progress 09/01/19 to 04/30/20

    Outputs
    Target Audience: Nothing Reported Changes/Problems:The major problem encountered was an inability to recover HDR-mediated editing in these experiments. What opportunities for training and professional development has the project provided?The project afforded an opportunity for genome editing gRNA design and testing by technical personnel. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

    Impacts
    What was accomplished under these goals? Multiple guide RNAs were designed and tested against the targeted maize sh2 gene to determine those with the highest likelihood of generating a double-stranded break that could be repaired by HDR as intended.

    Publications


      Progress 09/01/18 to 04/08/20

      Outputs
      Target Audience: Nothing Reported Changes/Problems:The major problem encountered was that HDR-mediated genome edited maize events were not recovered. As such, the intended outputs of the project were not able to be pursued as initially envisioned. What opportunities for training and professional development has the project provided?The project offered opportunities for molecular biology and plant transformation personnel to design and test guide RNAs intended for editing of a high-value trait gene, and to explore the experimental parameters that could contribute to HDR-mediated editing as opposed to the more common NHEJ-mediated editing. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

      Impacts
      What was accomplished under these goals? Multiple guide RNAs were screened for genome editing activity in the maize gene that was the target of these experiments. HDR experiments were performed but no HDR-mediated genome editing events were recovered unfortunately. As such goal #3 could not be pursued as envisioned.

      Publications


        Progress 09/01/18 to 08/31/19

        Outputs
        Target Audience: Nothing Reported Changes/Problems:As described in previous sections, HDR-mediated editing was not detected in initial experiments so troubleshooting experiments are ongoing, consistent with those described in the SBIR application. What opportunities for training and professional development has the project provided?The scientists working on the project have had the opportunity to modify existing plant transformation protocols and plant molecular characterization protocols to improve the generation and characterization of maize events, and have had the opportunity to communicate the results of their work internally within the company. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Troubleshooting experiments are ongoing to identify more optimal combinations of nuclease and guide RNAs and other associated genetic elements required for genome editing. Upon identifying more optimal editing conditions, new attempts at HDR-mediated gene conversion will be made.

        Impacts
        What was accomplished under these goals? Multiple nuclease/guide RNA combinations were tested for maize genome editing with the aim of identifying HDR-mediated edits in the targeted gene. Following genotyping of several thousand regenerated maize plants, unfortunately no suitable edits were identified. Multiple troubleshooting experiments were planned, consistent with the potential pitfalls identified in the SBIR application, and these experiments are currently underway in an attempt to further optimize the editing system components. Through these initial experiments, numerous transformation protocol improvements were made that allowed for the regeneration of a large number of potentially edited plants from limited amounts of starting material, resulting in pipeline improvements for the company's transformation and genome editing efforts.

        Publications