Location: Plant, Soil and Nutrition Research
Project Number: 8062-21000-050-027-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2023
End Date: May 31, 2026
Objective:
Provitamin A carotenoid turnover during storage of Golden Rice is a serious problem. This proposed research aims to engineer Golden Rice with enhanced provitamin A level and storage stability. The work will apply and test the knowledge and genetic tools we discovered in other plant systems in a major staple crop.
The objectives of this agreement are:
Objective 1: Improve beta-carotenoid storage capacity in Golden Rice endosperm by regulating chromoplast biogenesis and number.
Objective 2: Increase beta-carotenoid availability in Golden Rice endosperm by limiting its metabolic conversion.
Objective 3: Enhance post-harvest stability of beta-carotene in Golden Rice seeds by alleviating its degradation.
Approach:
Introduce R115H mutation in the Orange protein through base editing and increase expression of PDV1 in the endosperm through gene activation; Screen alternative up-regulatory mutations in the Orange protein through CRISPR/Cas mediated random mutagenesis; Generate BCH1, CCD1, and CCD4a knock-out lines of Golden Rice; Increase expression of HGGT through gene activation; Molecular and biochemical characterization of individual edited lines.