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Background: Organic acids and anthocyanins are the most important compounds for the flavor and nutritional quality of citrus fruit. However, there are few reports on the involvement of co-regulation of citrate and anthocyanin metabolism. Here, we performed a comparative transcriptome analysis to elucidate the genes and pathways involved in both citrate and anthocyanin accumulation in postharvest citrus fruit with 'Tarocco' blood orange (TBO; high accumulation) and 'Bingtangcheng' sweet orange (BTSO; low accumulation). Results: A robust core set of 825 DEGs were found to be temporally associated with citrate and anthocyanin accumulation throughout the storage period through transcriptome analysis. Further according to the results of weighted gene coexpression correlation network analysis (WGCNA), the turquoise and brown module was highly positively correlated with both of the content of citrate and anthocyanin, and p-type ATPase (PH8), phosphoenolpyruvate carboxylase kinase (PEPCK), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonoid 3'-hydroxylase (F3'H) and glutathione S transferase (GST) were considered key structural genes. Moreover, MYB family transcription factor (PH4), Zinc finger PHD-type transcription factor (CHR4, HAC12), Zinc finger SWIM-type transcription factor (FAR1) and Zinc finger C3H1-type transcription factor (ATC3H64) were considered hub genes related to these structural genes. Further qRT-PCR analysis verified that these transcription factors were highly expressed in TBO fruit and their expression profiles were significantly positively correlated with the structural genes of citrate and anthocyanin metabolism as well as the content of citrate and anthocyanin content. Conclusions: The findings suggest that the CHR4, FAR1, ATC3H64 and HAC12 may be the new transcription regulators participate in controlling the level of citrate and anthocyanin in postharvest TBO fruit in addition to PH4. These results may providing new insight into the regulation mechanism of citrate and anthocyanin accumulation in citrus fruit. [ABSTRACT FROM AUTHOR]

Background: The diseases caused by avian leukosis virus subgroup J (ALV-J) has become a serious problem in the poultry. Due to largely ineffective vaccines, new control measures are needed to be developed. RNA interference (RNAi) has been developed a promising measure for antivirus in poultry., Methods: In this study, miRNA-embedded siRNA interference was designed and used to inhibit ALV-J replication in vitro and in vivo. Each sequence of target siRNA derived from the gag (p15), pol (p32), env (gp85) and LTR (U3) gene of ALV-J was embedded into mouse miR-155 backbone as a pre-miRNA hairpin oligonucleotide sequence. After annealing, they were cloned into pcDNA6.2-GW/EmGFP-miR vector, respectively. For detecting the interference effect, recombinant vectors were introduced into DF-1 cells and day-old SPF chickens that infected with ALV-J., Results: In vitro, single target interference showed effective inhibition of reducing 74% ~ 85% mRNA of ALV-J. Double targets showed more efficient inhibition of reducing 96% ~ 98% mRNA of ALV-J. In vivo, chicks were inoculated with each recombinant plasmid in peritoneal cavity at day of hatch, and monitored infection status at interval 1 day postinfection for 4 weeks. Delivery of single target or double targets miRNA significantly reduced viremia and pathogenicity caused by ALV-J in vivo, especially the double targets., Conclusions: These data demonstrated that the miRNA-embedded siRNA interference is an efficient method for inhibition of ALV-J replication, especially double targets.