Project description:Shrub willow (Salix spp.), a short rotation woody biomass crop, has superior properties as a perennial energy crop for the Northeast and Midwest US. However, the insect pest potato leafhopper Empoasca fabae (Harris) (PLH) can cause serious damage and reduce yield of susceptible genotypes. Currently, the willow cultivars in use display varying levels of susceptibility under PLH infestation. However, genes and markers for resistance to PLH are not yet available for marker-assisted selection in breeding. In this study, transcriptome differences between a resistant genotype 94006 (S. purpurea) and a susceptible cultivar ‘Jorr’ (S. viminalis), and their hybrid progeny were determined. Over 600 million RNA-Seq reads were generated and mapped to the Salix purpurea reference transcriptome. Gene expression analyses revealed the unique defense mechanism in resistant genotype 94006 that involves PLH-induced secondary cell wall modification. In the susceptible genotypes, genes involved in programed cell death were highly expressed, explaining the necrosis symptoms after potato leafhopper feeding. Overall, the discovery of resistance genes and defense mechanisms provides new resources for shrub willow breeding and research in the future.
Project description:Salt responsive genes were identified in chinese willow (Salix matsudana) after the plants were treated with 100 mM NaCl. for 48 hours We used microarrays to identify genes responsible for combating salt stress. Those up-regulated during the NaCl treatment may protect the plants from damages caused by salt stress.
Project description:In order to screening the responsive miRNAs and target genes of willow under salt stress, the 30-day-old plants were exposed to the salt solution (100 mmol L-1 NaCl) for 0 h and 2 d. then RNA isolated from root and stem tissues for the same time point were mixed respectively in equal amounts for small RNA (sRNA) sequencing. sRNAs with 16–30 nt were separated from 1 µg total RNA by size fractionation. Subsequently, the selected sRNA fragments were ligated with specialized adaptors to the 5’ and 3’ ends (Illumina) using T4 RNA ligase. Then, the ligated RNAs were reverse transcribed and amplified for sequencing using Illumina Hiseq2500 (LC Sciences, Hangzhou, China). Salt stress-responsive miRNAs were identified by comparing the expression levels of miRNAs between the two libraries. Equal amounts of all 2 RNA samples were mixed together to construct one degradome library, and then sent to Hangzhou LC-Bio Co., Ltd (Hangzhou, China) for sequencing by Illumina Genome Analyzer GA-I (Illumina, San Diego, CA, USA).
Project description:Salt responsive genes were identified in chinese willow (Salix matsudana) after the plants were treated with 100 mM NaCl. for 48 hours We used microarrays to identify genes responsible for combating salt stress. Those up-regulated during the NaCl treatment may protect the plants from damages caused by salt stress. 2 month-old S. matsudana plants which were treated with 100 mM NaCl and control plants were used for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain salt responsive genes that protect the plants from stress injury.Those differentially expressed genes identified by the microarray would help to understand the mechanism of S. matsudana reacting to salt stress.
Project description:Background: Saprobic fungi are the predominant industrial sources of Carbohydrate Active enZymes (CAZymes) used for the saccharification of lignocellulose during the production of second generation biofuels. The production of more effective enzyme cocktails is a key objective for efficient biofuel production. To achieve this objective, it is crucial to understand the response of fungi to lignocellulose substrates. Our previous study used RNA-seq to identify the genes induced in Aspergillus niger in response to wheat straw, a biofuel feedstock, and showed that the range of genes induced was greater than previously seen with simple inducers [GSE33852]. Results: In this work we used RNA-seq to identify the genes induced in A. niger in response to short rotation coppice willow and compared this with the response to wheat straw from our previous study, at the same time-point. The response to willow showed a large increase in expression of genes encoding CAZymes. Genes encoding the major activities required to saccharify lignocellulose were induced on willow such as endoglucanases, cellobiohydrolases and xylanases. The transcriptome response to willow had many similarities with the response to straw with some significant differences in the expression levels of individual genes which are discussed in relation to differences in substrate composition or other factors. Differences in transcript levels include higher levels on wheat straw from genes encoding enzymes classified as members of GH62 (an arabinofuranosidase) and CE1 (a feruloyl esterase) CAZy families whereas two genes encoding endoglucanases classified as members of the GH5 family had higher transcript levels when exposed to willow. There were changes in the cocktail of enzymes secreted by A. niger when cultured with willow or straw. Assays for particular enzymes as well as saccharification assays were used to compare the enzyme activities of the cocktails. Wheat straw induced an enzyme cocktail that saccharified wheat straw to a greater extent than willow. Genes not encoding CAZymes were also induced on willow such as hydrophobins as well as genes of unknown function. Several genes were identified as promising targets for future study. Conclusions: By comparing this first study of the global transcriptional response of a fungus to willow with the response to straw, we have shown that the inducing lignocellulosic substrate has a marked effect upon the range of transcripts and enzymes expressed by A. niger. The use by industry of complex substrates such as wheat straw or willow could benefit efficient biofuel production.
Project description:Background: Saprobic fungi are the predominant industrial sources of Carbohydrate Active enZymes (CAZymes) used for the saccharification of lignocellulose during the production of second generation biofuels. The production of more effective enzyme cocktails is a key objective for efficient biofuel production. To achieve this objective, it is crucial to understand the response of fungi to lignocellulose substrates. Our previous study used RNA-seq to identify the genes induced in Aspergillus niger in response to wheat straw, a biofuel feedstock, and showed that the range of genes induced was greater than previously seen with simple inducers [GSE33852]. Results: In this work we used RNA-seq to identify the genes induced in A. niger in response to short rotation coppice willow and compared this with the response to wheat straw from our previous study, at the same time-point. The response to willow showed a large increase in expression of genes encoding CAZymes. Genes encoding the major activities required to saccharify lignocellulose were induced on willow such as endoglucanases, cellobiohydrolases and xylanases. The transcriptome response to willow had many similarities with the response to straw with some significant differences in the expression levels of individual genes which are discussed in relation to differences in substrate composition or other factors. Differences in transcript levels include higher levels on wheat straw from genes encoding enzymes classified as members of GH62 (an arabinofuranosidase) and CE1 (a feruloyl esterase) CAZy families whereas two genes encoding endoglucanases classified as members of the GH5 family had higher transcript levels when exposed to willow. There were changes in the cocktail of enzymes secreted by A. niger when cultured with willow or straw. Assays for particular enzymes as well as saccharification assays were used to compare the enzyme activities of the cocktails. Wheat straw induced an enzyme cocktail that saccharified wheat straw to a greater extent than willow. Genes not encoding CAZymes were also induced on willow such as hydrophobins as well as genes of unknown function. Several genes were identified as promising targets for future study. Conclusions: By comparing this first study of the global transcriptional response of a fungus to willow with the response to straw, we have shown that the inducing lignocellulosic substrate has a marked effect upon the range of transcripts and enzymes expressed by A. niger. The use by industry of complex substrates such as wheat straw or willow could benefit efficient biofuel production. Six samples in total consisting of duplicate shake flask Aspergillus niger cultures from three conditions: glucose 48 h, willow 24 h, willow 24 h + glucose 5 h
Project description:To provide a transcriptome resource for identification of transcripts where abundance correlated with developmental changes in willow plantlets derived from bud culture after transfer to soil.
Project description:<p>Shrub willow has strong adaptability, large biomass and short rotation period. Colorful willow barks have great ornamental and economic value. To study the color regulation mechanism, metabolomics and transcriptomics were used to analyze the purple, green and red barks. In the positive mode, a total of 1639 metabolites were identified and 1026 metabolites in negative mode. Flavone and flavonol biosynthesis (ko00944), flavonoid biosynthesis (ko00941), were all enriched in the 3 groups G vs P (G/P), G vs R (G/R) and P vs R (P/R). A total of 12 flavone and flavonol biosynthesis metabolites were isolated. A total of 448,839,796 raw reads were obtained with Q30 more than 93.15%. In the G/P, G/R and P/R groups, 27, 28 and 21 genes were enriched in the flavonoid biosynthesis (ko00941). The expression of CHS, ANS, DFR, ANR in the flavonoid biosynthesis pathway was the most in red. The content of canthaxanthin in purple bark was 10x more than green and 6x than red. The integration of metabolites and genes indicated the role of pelargonidin and canthaxanthin in regulating red and purple color pigment. Our research provides a fundamental basis for colorful willow breeding.</p>