Project description:ngs2014_07_hevea-hevea_tpd-seq-RNAseq analysis of latex samples from healthy and Tapping Panel Dryness-affected trees.-Identification of Tapping Panel Dryness (TPD)-affected trees in a polyclonal trials grown under standard condition. Trees were tapped since November 2010 every 2 days. Latex yield and TPD occurrence were monitored as well as latex RNA samples were collected twice a year for further analysis. At the end of the experiment, gene expression in latex of healthy and TPD trees were compared.
Project description:Nutural rubber (NR) production, latex is harvested by periodical tapping of the trunk bark. Ethylene enhances and prolongs latex flow and latex regeneration. Ethephon, which is an ethylene-releasing compound, applied to the trunk before tapping usually results in a 1.5- to 2-fold increase in latex yield. We investigated gene expression in response to ethephon treatment using Pará rubber tree seedlings as a model system. After ethephon treatment, 3,270 genes showed significant differences in expression compared with the mock treatment. Genes associated with carotenoids, flavonoids, and abscisic acid biosynthesis were significantly upregulated by ethephon treatment, which might contribute to an increase in latex flow. Genes associated with secondary cell wall formation were downregulated, which might be because of the reduced sugar supply. Given that sucrose is an important molecule for NR production, a trade-off may arise between NR production and cell wall formation for plant growth and for wound healing at the tapping panel.
Project description:Tapping panel dryness (TPD) seriously affects the natural rubber (NR) production of Hevea brasiliensis (rubber tree). Several studies have speculated that TPD influences NR biosynthesis in the latex of rubber trees based on the expression changes of NR biosynthesis-related genes. In this study, iTRAQ analysis of latex were carried out to reveal the molecular mechanism of TPD affecting rubber trees NR biosynthesis activity and molecular weight.
Project description:This study is committed to de novo sequencing and comparative analysis of the transcriptomes of healthy (H) and Tapping panel dryness (TPD)-affected (T) rubber trees to identify the genes and pathways related to the TPD. Total raw reads of 34,632,012 and 35,913,020 bp were obtained from H and T library, respectively using Illumina Hiseq 2000 sequencing technology. De novo assemblies yielded 141,456 and 169,285 contigs, and 96,070 and 112,243 unigenes from H and T library, respectively. Among 66535 genes, 107021 genes were identified as differential expressed genes between H and T library via comparative transcript profiling. A majority of genes involved in natural rubber biosynthesis and jasmonate synthesis with most potential relevance in TPD occurrence were found to be differentially expressed. In TPD-affected trees, the expression of most genes related to the latex biosynthesis and jasmonate synthesis was severely inhibited and it probably the direct cause of the TPD. Our de novo transcriptome data sets provide a significant resource for the discovery of genes related to TPD and improve our understanding the occurrence and maintainace of TPD.
Project description:Ethylene is commonly used as a latex stimulant of Hevea brasiliensis by application of ethephon (chloro-2-ethylphosphonic acid); however, the molecular mechanism by which ethylene increases latex production is not clear. To better understand the effects of ethylene stimulation on the laticiferous cells of rubber trees, a latex expressed sequence tag (EST)-based complementary DNA microarray containing 2973 unique genes (probes) was first developed and used to analyze the latex gene expression changes at three different time-points after ethephon treatment: 8, 24 and 48 h. Transcript levels of 163 genes were significantly altered with fold-change values ⥠2 or ⤠â2 (q-value < 0.05) in ethephon-treated compared with control rubber trees. Of the 163 genes, 92 were up-regulated and 71 down-regulated. The microarray results were further confirmed using real-time quantitative reverse transcript-PCR for 20 selected genes. Analysis used the 8, 24 or 48 h control latex RNA samples comparison to the ET stimulated 8, 24 or 48 h latex RNA samples. Each sample included three independent biological replicates, and each replicate comprised the latex collected from six trees.
Project description:Ethylene is commonly used as a latex stimulant of Hevea brasiliensis by application of ethephon (chloro-2-ethylphosphonic acid); however, the molecular mechanism by which ethylene increases latex production is not clear. To better understand the effects of ethylene stimulation on the laticiferous cells of rubber trees, a latex expressed sequence tag (EST)-based complementary DNA microarray containing 2973 unique genes (probes) was first developed and used to analyze the latex gene expression changes at three different time-points after ethephon treatment: 8, 24 and 48 h. Transcript levels of 163 genes were significantly altered with fold-change values ≥ 2 or ≤ –2 (q-value < 0.05) in ethephon-treated compared with control rubber trees. Of the 163 genes, 92 were up-regulated and 71 down-regulated. The microarray results were further confirmed using real-time quantitative reverse transcript-PCR for 20 selected genes.
2016-06-01 | GSE74060 | GEO
Project description:Transcriptome sequencing of tapping panel dryness affected rubber trees
Project description:We report here the use of next-generation massively parallel sequencing technologies and de novo transcriptome assembly to gain insight into the wide range of transcriptome of two Hevea brasiliensis clones (RY8-79 and PR107). The output of sequenced data showed that more than 26 million sequence reads with average length of 90nt were generated in both clones. Totally 51829 unigenes (mean size = 640 bp) were assembled through transcriptome de novo assembly, which represent more than 16-fold of all the sequences of Hevea brasiliensis deposited in the GenBank. Assembled sequences were annotated with gene descriptions, gene ontology and clusters of orthologous group terms. Base on limit rule with FDR≤0.001 and |log2 Ratio|≥1, 6726 different expression unigenes (3018 up and 3708 down) were detected as PR107 versus RY8-79. Functional analysis showed mass of categories were reprogrammed between two clones, which relate latex generation and expelling difference between them. As a comparative transcriptome analysis, the results obtained here will greatly expand our understanding of physiological differences among varieties in molecular level and will contribute t The transcriptome of latex in Hevea brasiliensis