Location: Plant, Soil and Nutrition Research
Project Number: 8062-21000-047-027-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 12, 2020
End Date: Sep 30, 2023
To apply genome editing technologies to manipulate tomato functional genes or regulatory elements to generate novel genetic materials conferring enhanced disease resistance to tomato yellow leaf curl virus.
The present experimental design will focus only on the first stage in proof of concept. Research in Ithaca, NY will include participation in all three activities outlined below with an emphasis on development of gene editing constructs (item 1). Prior to project initiation, gene targets with potential to confer or regulate disease resistance or susceptibility will be identified for genetic manipulation in tomato (e.g., gene editing, RNAi or ectopic expression). Specific diseases of tomato of interest both in the Philippines and the U.S. will be initially identified and 1-3 gene targets likely to influence one or several important disease problems (e.g. tomato yellow leaf curl virus) will be identified. As a proof-of-concept, ARS scientists in Ithaca, NY will focus their efforts in developing novel tomato genetic materials with resistance to Tomato yellow leaf curl virus (TYLCV). There are currently six known Ty resistance genes in tomato against TYLCV. Four of these genes (Ty1, Ty2, TY3 and ty5) have been identified and sequenced and two others (Ty4 and Ty6) mapped. The ty-5 is a recessive gene which could be a good target for genome editing. Other five Ty genes are dominant and would need to target some regulatory elements to regulate the expression of these genes to improve resistance to TYLCV. The terms of a research agreement (i.e., Material Transfer Research Agreement) will also be agreed upon. 1. Develop and validate gene editing and/or expression constructs for selected genes of interest in collaboration with visiting Philippine scientist(s). (4-6 months) 2. Transformation and genetic assessment to validate gene edits or transgene integrations - performed in the U.S. and/or the Philippines. (1 year) 3. Develop lines with validated transgenes for evaluation and assess the phenotypes. (6-12 months) The Plant Soil and Nutrition Research Unit in Ithaca, NY and the U.S. Vegetable Laboratory in Charleston, South Carolina can host some visiting scholars from the Philippines throughout the project period to enhance collaboration efforts and facilitate technology transfer. Future Directions: Following the proof of concept research activities described in this proposal, field trials will be set up both in the U.S. and the Philippines to validate the field performance of these selected gene-edited materials for target disease resistance. These field trials may be expected to take approximately two years. The final stage will be deregulation and commercialization of the products in the U.S. and the Philippines, which may be expected to take approximately one to two years. The proposed research activities use tomato as a model system. Once some breakthroughs are achieved on disease resistance for tomato using gene-editing and/or other biotechnological approaches, the same strategy and technology could be applied to other crops and traits of mutual interest to the U.S. and the Philippines.