Project description:In the present study, we employed the high-throughput sequencing technology to profile miRNAs in blueberry fruits. A total of 9,992,446 small RNA tags with sizes ranged from 18 to 30 nt were obtained, indicating that blueberry fruits have a large and diverse small RNA population. Bioinformatic analysis has identified 412 conserved miRNAs, which belong to 20 families, and 57 predicted novel miRNAs likely unique to blueberries. Among them, expression profiles of 5 conserved miRNAs were validated by stem loop qRT-PCR. Furthermore, the potential target genes of the abundant conserved and novel miRNAs were predicted and subjected for Gene Ontology (GO) annotation. Enrichment analysis of the GO-represented biological processes and molecular functions revealed that these target genes were involved in a wide range of metabolic and developmental processes. This study is the first report on genome-wide miRNA profile analysis in blueberry and it provides a useful resource for further elucidation of the functional roles of miRNAs during fruit development and ripening.
Project description:Environmental factors play an important role in anthocyanin biosynthesis, and potassium, an essential nutrient for blueberry growth, can act as an enzyme activator. However, few reports exist on the transcriptional and anthocyanin metabolic changes in blueberries regulated by potassium. In this study, blueberries treated with potassium at different stages were compared for changes in enzyme activity, transcription, and metabolism related to anthocyanin synthesis. The results showed that potassium treatment significantly enhanced the activities of key enzymes F3H, F3'5'H, and UFGT in the anthocyanin synthesis pathway of blueberry fruit. Metabolomic results indicated that the contents of malvidin, petunidin, and delphinidin were higher with potassium fertilization, and potassium treatment promoted the early color change of blueberry fruit. The transcriptome analysis identified 102 glucose metabolism-related genes and 12 differential potassium transport genes potentially involved in potassium-regulated anthocyanin synthesis and accumulation. It was found that thirteen genes relate to anthocyanin synthesis. UFGT, F3H, CHI, HCT, C12RT1, DFR, and F3'5'H were all closely associated with potassium-controlled flavonoid and anthocyanin metabolite synthesis. It provides valuable insights into the molecular mechanisms that regulate the synthesis of anthocyanins in blueberries.