Distinguished Research Fellow Academia Sinica Taipei, Taipei, Taiwan (Republic of China)
Body of Abstract: Genome-wide association study (GWAS) has improved our understanding of complex traits, but challenges exist in distinguishing causation versus association caused by linkage disequilibrium. Instead, the transcriptome-wide association study (TWAS) detects direct associations between expression levels and phenotypic variations, providing an opportunity to prioritize candidate genes better. We have established an analytical platform using publicly available databases from rosette leaves of Arabidopsis accessions. The feasibility of our TWAS was evidenced by identifying associated genes as formerly known factors related to growth allometry, metabolite production, and flowering time. To further reveal the genes regulating responses to phosphate (Pi) starvation, we generated transcriptomes from the roots of 190 Arabidopsis natural accessions grown under Pi-adequate or Pi-free media. Several Pi-related traits were subjected to association studies, such as the shoot Pi content, Pi-uptake activity, and the protein level of Pi transporters. Several well-known Pi starvation regulators were identified, which validates the efficiency of our newly generated databases for TWAS. Several new candidate genes significantly associated with the Pi-related traits were also identified and awaited functional validation. Together, our transcriptome-to-phenotype associations allowed us to discover potential regulators for Pi-related traits.