Significant Reduction of the Expression of Peach ( Prunus persica L. Batsch) Allergen-Encoding Genes by Fruit Bagging with Opaque Paper.

Freshly consumed peaches ( Prunus persica L. Batsch) can cause allergic reactions in the worldwide population because of the presence of four classes of allergens (Pru p 1, Pru p 2, Pru p 3, and Pru p 4). Fruit bagging has been widely practiced in peach cultivation to improve fruit quality; however, its effect on the expression of peach allergen-encoding genes remains unknown. In this study, the influence of fruit bagging with opaque paper bags on the major peach allergen-encoding genes, including Pru p 1.01, Pru p 1.06B, Pru p 2.01B, Pru p 2.02, Pru p 3.01, Pru p 4.01, and Pru p 4.02, were measured by means of real-time PCR. A significant reduction in transcript accumulation was observed for all of the selected genes in the epicarps of the bagged peach fruits, whereas slight increases were observed in the mesocarps for these genes, with the two exceptions of Pru p 2.02 and Pru p 3.01. For most of these genes, much higher transcripts were determined in the epicarps than in the mesocarps. Taken together, a significant reduction in the transcription rate of the allergen-encoding genes in the whole peach fruit was achieved by shading with opaque paper bags. According to these data, modifications in growing practices of peach may help to obtain fruits with lower levels of allergens and thus contribute to reducing potential allergenic risks in consumers.

Effect of salt-stress on gene expression in citrus roots revealed by RNA-seq.

Citrus, as one of the most economically important fruits worldwide, is adversely affected by salinity stress. However, its molecular mechanisms underlying salinity tolerance are still not clear. In this study, next-generation RNA-seq technology was applied to analyze the gene expression profiling of citrus roots at 3 time points over a 24-h period of salt treatment. A total of 1831 differentially expressed genes (DEGs) were identified. Among them, 1195 and 1090 DEGs were found at 4 and 24 h, of which 454 were overlapped. Based on functional annotation, the salt overly sensitive (SOS) and reactive oxygen species (ROS) signaling pathways were found to be involved. Meanwhile, we found that hormone metabolism and signaling played important roles in salt stress. In addition, a multitude of transcription factors (TFs) including WRKY, NAC, MYB, AP2/ERF, bZIP, GATA, bHLH, ZFP, SPL, CBF, and CAMTA were identified. The genes related to cell wall loosening and stiffening (xyloglucan endotransglucosylase/hydrolases, peroxidases) were also involved in salt stress. Our data not only provided a genetic resource for discovering salt tolerance-related genes, but also furthered our understanding of the molecular mechanisms underlying salt tolerance in citrus.