Project description:Quantitative trait loci mapping and transcriptome analysis reveal candidate genes regulating the response to ozone in Arabidopsis thaliana
Project description:Purpose:The red coloration of apple (Malus × domestica Borkh.) is due to the accumulation of anthocyanins in the fruit peel. Light is essential for anthocyanin biosynthesis in apple.Apple peel can quickly turn red under light conditions after unbagging. Therefore, the implementation of transcriptome sequencing to find genes that promote anthocyanin accumulation in response to light signals is necessary to clarify the mechanism of light-induced anthocyanin accumulation in apple peel.
Project description:Background: Anthocyanins are the most important compounds for nutritional quality and economic values of blood orange. However, there are few reports on the pre-harvest treatment accelerate the accumulation of anthocyanins in postharvest blood orange fruit. Here, we performed a comparative Transcriptome and metabolomics analysis to elucidate the underlying mechanism involved in seasonal drought (SD) treatment during fruit expansion stage on anthocyanin accumulation in postharvest ‘Tarocco’ blood orange fruit. Results: Our results showed that SD treatment slowed down the fruit enlargement and increased the sugar accumulation during fruit development and matured period. Obviously, under SD treatment, the accumulation of anthocyanin in blood orange fruit during postharvest storage was significantly accelerated and markedly higher than that in CK. Meanwhile, the total flavonoids and phenols contents and antioxidant activity in SD treatment fruit were also sensibly increased during postharvest storage. Based on metabolome, we found that substrates required for anthocyanin biosynthesis, such as amino acids and their derivatives, and phenolic acids, have significantly accumulated and higher in SD treated mature fruit compared with that of CK. Further according to the results of transcriptome data and weighted gene coexpression correlation network analysis (WGCNA) analysis, phenylalanine ammonia-lyase (PAL3) was considered key structural gene. qRT-PCR analysis verified that the PAL3 was highly expressed in SD treated postharvest stored fruit and was significantly positively correlated with the anthocyanin content. Moreover, we found that other structural genes in anthocyanin biosynthesis pathway were also upregulated under SD treatment through transcriptome data and qRT-PCR analysis. Conclusions: The findings suggest that SD treatment promotes the accumulation of substrates necessary for anthocyanin biosynthesis during fruit ripening process, and activates the expression of anthocyanin biosynthesis pathway genes during postharvest storage period, especially PAL3, co-contributed to the rapid accumulation of anthocyanin. The present study provides a theoretical basis for postharvest quality control and water-saving utilization of blood orange fruit.
Project description:n Arabidopsis and other species, anthocyanin accumulation specifically depends on light signaling. The CONSTITUTIVELY PHOTOMORPHOGENIC1/SUPPRESSOR OF PHYA-105 (COP1/SPA) complex is required for the control of anthocyanin biosynthesis in response to light, but the precise mechanism underlying this process is largely unknown. Here we report that Increase in BONSAI Methylation 1 (IBM1), a JmjC domain-containing histone demethylase, participates in the regulation of light-induced anthocyanin biosynthesis in Arabidopsis. Loss-of-function mutations of IBM1 lead to accelerated anthocyanin accumulation in high light. We further identified that IBM1 is directly associated with SPA1/2/3 chromatin in vivo, whereas knockout of IBM1 resulted in an elevated level of H3K9 methylation and DNA non-CG sites within SPA genes, thereby repressing their expression. Transgenic ibm1 plants overexpressing SPA1demonstrated that SPA1 was capable of complementing the mutant phenotype. Our results reveal a novel mechanism that controls the epigenetic regulation of anthocyanin biosynthesis and offer insight into how plant adapt to high light stress. This study could contribute to a better understanding of the linkage between light signaling and anthocyanin biosynthesis in plants
Project description:Background: Pear is one of the most important fruit crops worldwide. Anthocyanins and procyanidins (PAs) are important secondary metabolites that affect the appearance and nutritive quality of pear. However, few studies have focused on the molecular mechanism underlying anthocyanin and PA accumulation in pear. Results: We conducted metabolome and transcriptome analyses to identify candidate genes involved in anthocyanin and PA accumulation in young fruits of the pear cultivar ‘Clapp Favorite’ (CF) and its red mutation cultivar ‘Red Clapp Favorite’ (RCF). Gene–metabolite correlation analyses revealed a ‘core set’ of 20 genes that were strongly correlated with 10 anthocyanin and seven PA metabolites. Of these, PcGSTF12 was confirmed to be involved in anthocyanin and PA accumulation by complementation of the tt19-7 Arabidopsis mutant. Interestingly, PcGSTF12 was found to be responsible for the accumulation of procyanidin A3, but not petunidin 3, 5-diglucoside, opposite to the function of AtGSTs in Arabidopsis. Transformation with PcGSTF12 greatly promoted or repressed genes involved in anthocyanin and PA biosynthesis, regulation, and transport. Electrophoretic mobility shift and luciferase reporter assays confirmed positive regulation of PcGSTF12 by PcMYB114. Conclusion: These findings identify a core set of genes for anthocyanin and PA accumulation in pear. Of these, PcGSTF12 was confirmed to be involved in anthocyanin and PA accumulation. Our results also identified an important anthocyanin and PA regulation node comprising two core genes, PcGSTF12 and PcMYB114. These results provide novel insights into anthocyanin and PA accumulation in pear and represent a valuable data set to guide future functional studies and pear breeding.
Project description:Purple-grain wheat are caused by anthocyanin accumulation in the seed coat. But little is known about molecular mechanism of anthocyanin biosynthesis. The anthocyanin biosynthesis and accumulation were affected by light in purple-grain wheat. The spikes of purple-grain wheat Luozhen No.1 were bagged with four-layer Kraft paper bags after pollination. To identify genes involved in the anthocyanin biosynthesis, we sequenced four pericarp cDNA libraries, D15 (15 DAP), D20 (20 DAP) of shading treatment, and L15 (15 DAP), L20 (20 DAP) of untreated control using an Illumina HiSeqTM 2000. After quality control, raw reads are filtered into clean reads which will be aligned to the reference sequences. The alignment data is utilized to calculate distribution of reads on reference genes and mapping ratio, and proceed with downstream analysis including gene and isoform expression, deep analysis based on gene expression (PCA/correlation/screening differentially expressed genes and so on),exon expression, gene structure refinement, alternative splicing, novel transcript prediction and annotation, SNP detection, Indel detection. Further, we also perform deep analysis based on different expression genes, including Gene Ontology (GO) enrichment analysis, Pathway enrichment analysis, cluster analysis, and finding transcriptor factor.