Project description:Bitter pit is the most important physiological disorder affecting apples. In order to ascertain the genetic bases of its incidence in apple fruit, a mapping population of ‘Braeburn’ (susceptible to bitter pit) × ‘Cameo’ (resistant to bitter pit) cultivars was used to map the trait over two growing seasons. RNA-Seq on pools of RNA extracted from fruits of three resistant and three susceptible to bitter pit progenies at post-fertilization and full maturity stages, permitted us to identify a number of candidate genes underlying genetic resistance/susceptibility to bitter pit.
Project description:T2R bitter receptors, encoded by Tas2r genes, are not only critical for bitter taste signal transduction but also important for defense against bacteria and parasites. However, little is known about whether and how Tas2r gene expression are regulated. Here, using single-cell assays for transposase-accessible chromatin with sequencing (scATAC-seq), we found that the chromatin accessibility of Tas2rs was highly cell type specific and lipopolysaccharide (LPS)-induced inflammation increased the accessibility of many Tas2rs. scATAC-seq also revealed substantial chromatin remodeling in immune response genes in taste tissue stem cells, suggesting potential long-term effects. Together, our results suggest an epigenetic mechanism connecting inflammation, Tas2r gene regulation, and altered bitter taste, which may explain heightened bitter taste that can occur with infections and cancer treatments.