Location: Vegetable Crops Research
Project Number: 5090-21000-069-32-I
Project Type: Interagency Reimbursable Agreement
Start Date: Feb 15, 2017
End Date: Feb 14, 2021
1. Fine genetic mapping and cloning of short hypocotyl (SH1) and long hypocotyl (LH1) genes 2. Understand molecular mechanisms of regulation of hypocotyl elongation in cucumber 3. Marker-assisted development short hypocotyl germplasm for cucumber breeding
Objective 1 1. We will use map-based cloning strategy to clone and characterize sh1 and lh1 genes for hypocotyl elongation. Near isogenic lines of each gene are being developed through marker-assisted backcrossing and phenotyping in both UV and UVB-free light conditions. Recombinants will be identified through flanking markers until the target gene region is narrowed down to less than 30kb. 2. Candidate genes in target regions will be identified and annotate. Objective 2 Functional characterization and understanding of regulatory network will be performed with the following experiments: 1. Quantitative PCR (qPCR) will be used to study expression dynamics in different tissues, development stages and light conditions 2. Allelic diversity of candidate genes will be examined in cucumber natural populations 3. Genetic transformation of candidate genes in Arabidopsis 4. Transcriptome profiling between of sh1 and lh1near isogenic lines with RNA-Seq to reveal regulatory network 5. Understand protein-protein interactions with the following techniques: year two hybrid (Y2H), pull-down assay, BiFC (Bimolecular fluorescence complementation) Objective 3 1. Near isogenic lines of LH1 and SH1 genes will be developed through marker-assisted backcrossing. 2. These lines will be evaluated in greenhouse and field trails for horticulturally important traits and their potentials in cucumber breeding.