Location: Crop Improvement and Genetics Research
Project Number: 2030-21220-003-013-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2024
End Date: Aug 31, 2027
Objective:
The overall goal of the project is to investigate the molecular responses of grape berries to wildfire smoke, focusing on factors that contribute to smoke taint. We will characterize gene expression changes induced by smoke exposure, examine the regulatory mechanisms involved, and test the roles of candidate genes using genome editing approaches.
We will pursue the following objectives:
1. Evaluate transcriptome changes in grape berries in response to smoke.
2. Identify candidate of smoke response regulators.
3. Test gene candidates by stable genome editing.
Approach:
This project utilizes Vitis vinifera cv. Pixie (hereafter referred to as Pixie) grapevines as a model system. Pixie was chosen because it produces fruit year-round, enabling continuous experimentation, and the UC Davis transformation facility successfully regenerates Pixie vines from transfected protoplasts. To leverage Pixie as a model system, we assembled a chromosome-scale diploid genome reference for Pixie. Additionally, we constructed a gene expression atlas of Pixie using RNAseq, covering 10 tissues [roots, stem, leaves (young, mature, dying), flowers, berries (green, pre-veraison, pre-harvest), and buds], each sequenced in triplicate. A total of 505 glycosyltransferase 1 (GT1) genes (263 in haplotype 1 and 242 in haplotype 2) were annotated in the Pixie genome using a custom HMM model of the PSPG box motif, derived from a comparative analysis of the GT1 family across nine annotated V. vinifera genomes (PN40024, Cabernet Franc, Cabernet Sauvignon, Chardonnay, Merlot, Pinot Noir, Riesling, Rubired, and Zinfandel).
