Project description:Background: Limited data are available on aluminum (Al)-toxicity-induced alterations of gene profiles in woody plants. Seedlings of Al-tolerant Citrus sinensis and Al-intolerant Citrus grandis were fertigated with nutrient solution containing 0 and 1.0 mM AlCl3â?¢6H2O. Thereafter, we investigated the Al-toxicity-induced alterations of transcriptomics in roots by RNA-Seq. Results: Using RNA-seq, we isolated 1293 (990) up- and 1377 (915) downregulated genes from Al-treated C. grandis (C. sinensis) roots. Clearly, gene expression was less affected by Al-toxicity in C. sinensis roots than in C. grandis ones. Several Al-toxicity-responsive genes homologous to known Al-tolerance genes: Al-activated malate transporter, multidrug and toxic compound extrusion (MATE), IRON REGULATED/ferroportin 1, sensitive to proton rhizotoxicity 1 and monogalactosyldiacylglycerol synthase were identified in citrus roots. However, Al-induced upregulation of all these genes was stronger in C. grandis roots than in C. sinensis ones except for MATEs. Genes related to signal transduction, and sulfur transport and metabolism might also play a role in the higher Al-tolerance of C. sinensis. Conclusions: This is the first comparative investigation of transcriptomic responses in Al-treated citrus roots. There were common and unique mechanisms for citrus Al-tolerance. These results provide a platform for further investigating the roles of genes possibly responsible for citrus Al-tolerance. Examination of mRNA levels in control and Al-treatment roots of C. grandis and C. sinensis with two biological replicates were generated by deep sequencing, using Illumina HiSeq 2000 device.
Project description:The postharvest senescence processes of citrus fruits were analyzed transcriptomic. The present study was aimed to: further uncover the rind-flesh communication of hesperidium; characterize the differential storage behaviors of different citrus varieties; reveal the important changes during storing process; and demonstrate the specific non-climacteric characteristics of citrus fruits. We chose four major table fruit varieties of citrus: satsuma mandarin (Citrus unshiu Marc) (M), ponkan (Citrus reticulata Blanco) (K), newhall navel orange (Citrus sinensis L. Osbeck) (O) and shatian pummelo (Citrus grandis Osbeck) (P). They were sampled every 10 days during 50 DAH (days after harvest), almost covering the commercial storage period of loose-skin citrus.
Project description:Seed developmental arrest is one of the early phenotypes of seed abortion. However, the molecular mechanism underlying seed developmental arrest of citrus is still unclear. In this study, laser capture microdissection (LCM) was used to accurately divide the seeds of seedless Ponkan ‘Huagan No.4’ (Citrus reticulata) (HG) and seeded Ponkan ‘Egan No.1’ (Citrus reticulata) (EG) into nucellus and integument/seed coat tissues. The captured tissues were used for subsequent RNA-seq. Moreover, single-molecule real-time (SMRT) sequencing was used to generate full-length transcripts of EG, which were used as reference transcripts for RNA-seq. These data can be utilized to analyse the causes of citrus seedlessness formation and the molecular regulatory network in the process of seed abortion.
Project description:Background: Limited data are available on aluminum (Al)-toxicity-induced alterations of gene profiles in woody plants. Seedlings of Al-tolerant Citrus sinensis and Al-intolerant Citrus grandis were fertigated with nutrient solution containing 0 and 1.0 mM AlCl3•6H2O. Thereafter, we investigated the Al-toxicity-induced alterations of transcriptomics in leaves by RNA-Seq. Results: Using RNA-seq, we isolated 1162 (181) up- and 496 (234) downregulated genes from Al-treated C. grandis (C. sinensis) leaves. Clearly, gene expression was less affected by Al-toxicity in C. sinensis leaves than in C. grandis ones. Several Al-toxicity-responsive genes homologous to known Al-tolerance genes: ALUMINUM SENSITIVE 3 (ALS3), multidrug and toxic compound extrusion (MATE), glutathione S-transferase (GST), L-galactose dehydrogenase(L-GalDH) and lipoxygenase (LOX) were identified in citrus leaves. Genes related to signal transduction, and sulfur transport and metabolism might also play a role in the higher Al-tolerance of C. sinensis. Conclusions: This is the first comparative investigation of transcriptomic responses in Al-treated citrus leaves. There were common and unique mechanisms for citrus Al-tolerance. These results provide a platform for further investigating the roles of genes possibly responsible for citrus Al-tolerance.
Project description:Background: Limited data are available on aluminum (Al)-toxicity-induced alterations of gene profiles in woody plants. Seedlings of Al-tolerant Citrus sinensis and Al-intolerant Citrus grandis were fertigated with nutrient solution containing 0 and 1.0 mM AlCl3•6H2O. Thereafter, we investigated the Al-toxicity-induced alterations of transcriptomics in roots by RNA-Seq. Results: Using RNA-seq, we isolated 1293 (990) up- and 1377 (915) downregulated genes from Al-treated C. grandis (C. sinensis) roots. Clearly, gene expression was less affected by Al-toxicity in C. sinensis roots than in C. grandis ones. Several Al-toxicity-responsive genes homologous to known Al-tolerance genes: Al-activated malate transporter, multidrug and toxic compound extrusion (MATE), IRON REGULATED/ferroportin 1, sensitive to proton rhizotoxicity 1 and monogalactosyldiacylglycerol synthase were identified in citrus roots. However, Al-induced upregulation of all these genes was stronger in C. grandis roots than in C. sinensis ones except for MATEs. Genes related to signal transduction, and sulfur transport and metabolism might also play a role in the higher Al-tolerance of C. sinensis. Conclusions: This is the first comparative investigation of transcriptomic responses in Al-treated citrus roots. There were common and unique mechanisms for citrus Al-tolerance. These results provide a platform for further investigating the roles of genes possibly responsible for citrus Al-tolerance.
Project description:Ovule developmental arrest is one of the early phenotypes of seed abortion. However, the molecular mechanism underlying ovule developmental arrest of citrus is still unclear. In this study, laser capture microdissection (LCM) was used to accurately divide the ovules of seedless Ponkan ‘Huagan NO.4’ (Citrus reticulata) (MT) and seeded Ponkan ‘Egan NO.1’ (Citrus reticulata) (WT) into nucellus and integument tissues. The captured tissues were used for subsequent RNA-seq. Moreover, single-molecule real-time (SMRT) sequencing was used to generate full-length transcripts of WT, which were used as reference transcripts for RNA-seq. These data can be utilized to analyse the causes of citrus seedlessness formation and the molecular regulatory network in the process of ovule abortion.
Project description:Fruit ripening in Citrus is not well understood at the molecular level. Knowledge of the regulatory mechanism of citrus fruit ripening at the post-transcriptional level in particular is lacking. Here, we comparatively analyzed the miRNAs and their targeted genes in a spontaneous late-ripening mutant, ?Fengwan? sweet orange (MT) (Citrus sinensis L. Osbeck), and its wild-type counterpart ('Fengjie 72-1', WT). Using high-throughput sequencing of small RNAs and RNA degradome tags, we identified 107 known and 21 novel miRNAs, as well as 225 target genes. A total of 24 miRNAs (16 known miRNAs and 8 novel miRNAs) were shown to be differentially expressed between MT and WT. The expression pattern of several key miRNAs and their target genes during citrus fruit development and ripening stages was examined. Csi-miR156k, csi-miR159 and csi-miR166d suppressed specific transcription factors (GAMYBs, SPLs and ATHBs) that are supposed to be important regulators involved in citrus fruit development and ripening. In the present study, miRNA-mediated silencing of target genes was found under complicated and sensitive regulation in citrus fruit. The identification of miRNAs and their target genes provide new clues for future investigation of mechanisms that regulate citrus fruit ripening.