ABSTRACT: Global Analysis of the Transcriptional Response of Chinese cabbage (Brassica rapa ssp. pekinensis) to Methyl Jasmonate Reveals JA Signaling on Enhancement of Secondary Metabolism Pathways
Project description:We conducted a RNA-Seq analysis of MeJA-treated Chinese cabbage leaf transcriptome. Total 14,619,469 sequence reads were generated to produce 27,461 detected genes, among which 1,451 genes were up-regulated and 991 genes were down-regulated as differentially expressed genes (DEGs) (log2 ratio â¥1, false discovery rate â¤0.001). More than 90% of the DEGs (2,278) were between 1.0- and 3.0-fold (log2 ratio). The most highly represented pathways by 1,674 annotated DEGs were related to âmetabolic pathwaysâ (333 members), âribosomeâ (314 members), âbiosynthesis of secondary metabolitesâ (218 members), âplant-pathogen interactionâ (146 members), and âplant hormone signal transductionâ (99 members). Fourteen genes involved in JA biosynthesis pathway were up-regulated. As many as 182 genes for the biosynthesis of several secondary metabolites were induced, and the level of indole glucosinolate was highly increased by MeJA treatment. The genes encoding sugar catabolism and some amino acids synthesis were up-regulated, which could supply structural intermediates and energy for the biosynthesis of secondary metabolites. The results demonstrated a high degree of transcriptional complexity with dynamic coordinated changes in global gene expression of Chinese cabbage in response to MeJA treatment. It expands our understanding of the complex molecular events on JA-induced plant resistance and accumulation of secondary metabolites. It also provides a foundation for further studies on the molecular mechanisms of different pathways in other Brassica crops under MeJA treatment. Transcriptomic analysis of MeJA-treated Chinese cabbage leaf
Project description:We conducted a RNA-Seq analysis of MeJA-treated Chinese cabbage leaf transcriptome. Total 14,619,469 sequence reads were generated to produce 27,461 detected genes, among which 1,451 genes were up-regulated and 991 genes were down-regulated as differentially expressed genes (DEGs) (log2 ratio ≥1, false discovery rate ≤0.001). More than 90% of the DEGs (2,278) were between 1.0- and 3.0-fold (log2 ratio). The most highly represented pathways by 1,674 annotated DEGs were related to “metabolic pathways” (333 members), “ribosome” (314 members), “biosynthesis of secondary metabolites” (218 members), “plant-pathogen interaction” (146 members), and “plant hormone signal transduction” (99 members). Fourteen genes involved in JA biosynthesis pathway were up-regulated. As many as 182 genes for the biosynthesis of several secondary metabolites were induced, and the level of indole glucosinolate was highly increased by MeJA treatment. The genes encoding sugar catabolism and some amino acids synthesis were up-regulated, which could supply structural intermediates and energy for the biosynthesis of secondary metabolites. The results demonstrated a high degree of transcriptional complexity with dynamic coordinated changes in global gene expression of Chinese cabbage in response to MeJA treatment. It expands our understanding of the complex molecular events on JA-induced plant resistance and accumulation of secondary metabolites. It also provides a foundation for further studies on the molecular mechanisms of different pathways in other Brassica crops under MeJA treatment.
Project description:Background: The growth and development of leaf and petiole have an important influence on the photosynthesis of plants. The research on molecular mechanism of leaf and petiole development is of great significance, whether it is to improve plant photosynthetic efficiency, cultivate varieties with high photosynthetic efficiency, or improve the yield of crops using leaves as food organs. In this study, we aimed to identify the mRNAs, long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs) related to leaf and petiole development in Chinese cabbage (Brassica campestris L. ssp. pekinensis). These data were then used to construct competitive endogenous RNA (ceRNA) networks, which can provide valuable information for better understanding the mechanism of leaf and petiole development. Results: In this study, the leaf and petiole of the baby Chinese cabbage inbred line ‘PHL’ were used as research materials for whole-transcriptome sequencing. A total of 10646 differentially expressed (DE) mRNAs, 303 DE lncRNAs, 7 DE circRNAs, and 195 DE miRNAs were identified between the leaf and petiole. Some transcription factors or proteins that play important roles in leaf and petiole development were identified, such as xyloglucan endotransglucosylase/hydrolase (XTH) protein, expansion protein, TCP15 transcription factor, bHLH transcription factor, LOB domain protein, cellulose synthase (CESA), MOR1-like protein, and plant hormone biosynthesis related genes. Additionally, we constructed a leaf and petiole development-related ceRNA regulatory network, and obtained 85 pairs of ceRNA relationships, including 71 DEmiRNA-DEmRNA, 12 DEmiRNA-DElncRNA and 2 DEmiRNA-DEcircRNA. Three LSH genes (BrLSH1, BrLSH2 and BrLSH3) with significant differential expression between leaf and petiole of baby Chinese cabbage were screened from transcriptome data for subcellular localization analysis and overexpression transgenic verification. The results showed that BrLSH1, BrLSH2 and BrLSH3 were nucleoprotein and BrLSH2 has an obvious inhibitory effect on the growth and development of Arabidopsis thaliana. Conclusions: Our results revealed the potential mRNAs and non-coding RNAs (ncRNAs) involved in leaf and petiole development, which laid a foundation for further research on the molecular mechanism of leaf and petiole development in Chinese cabbage.
Project description:Plants possess various defense strategies to counter attacks from microorganisms or herbivores. For example, plants reduce the cell-wall-macerating activity of pathogen- or insect-derived polygalacturonases (PGs) by expressing PG-inhibiting proteins (PGIPs). PGs and PGIPs belong to multi-gene families believed to have been shaped by an evolutionary arms race. The mustard leaf beetle Phaedon cochleariae expresses both active PGs and catalytically inactive PG pseudoenzymes. Previous studies demonstrated that (i) PGIPs target beetle PGs and (ii) the role of PG pseudoenzymes remains elusive, despite having been linked to the pectin degradation pathway. For further insight into the interaction between plant PGIPs and beetle PG family members, we combined affinity purification with proteomics and gene expression analyses, and identified novel inhibitors of beetle PGs from Chinese cabbage (Brassica rapa ssp. pekinensis). A beetle PG pseudoenzyme was not targeted by PGIPs, but instead interacted with PGIP-like proteins. Phylogenetic analysis revealed that PGIP-like proteins clustered apart from classical PGIPs but together with proteins, which have been involved in developmental processes. Our results indicate that PGIP-like proteins represent not only interesting novel PG inhibitor candidates in addition to classical PGIPs, but also fascinating new players in the arms race between herbivorous beetles and plant defenses.
Project description:Using 300K′-high density microarray covering the chinese cabbage whole genome, genome-wide expression analyses of cold stress conditions.
Project description:The leaf of Chinese cabbage is the major place of photosynthesis, the mutation of leaf may directly affect the rate of plant growth and development and the formation of leafy head, and ultimately influence the yield and quality of Chinese cabbage. We identified a developmentally retarded mutant (drm) exhibiting stable inheritance, which was derived from Chinese cabbage DH line âFTâ using a combination of isolated microspore culture and radiation treatment (60Co γ-rays). The drm exhibited slow growth and development at the seedling and heading stages, leading to the production of a tiny, leafy head, as well as chlorophyll-deficient leaves, especially in seedlings. Genetic analysis indicated that the phenotype of drm was controlled by a single recessive nuclear gene. Compared with wild-type line âFTâ, the drmâs chlorophyll content was significantly reduced and its chloroplast structure was abnormal. Moreover, the photosynthetic efficiency and chlorophyll fluorescence parameters were significantly decreased. The changes in leaf color, combined with these altered physiological characters may influence the growth and development of plant, ultimately resulting in the developmentally retarded phenotype of drm. To further understand the molecular regulatory mechanisms of phenotypic differences between âFTâ and drm, comparative transcriptome analysis were performed using RNA-Seq, a total of 338 differentially expressed genes (DEGs) were detected between âFTâ and drm. According to GO and KEGG pathway analysis, a number of DEGs which involved in the chlorophyll degradation and photosynthesis were identified, such as chlorophyllase and ribulose-1,5-bisphosphate carboxylase/oxygenase. In addition, the expression patterns of 12 DEGs, including three chlorophyll degradation- and photosynthesis-related genes and nine randomly selected genes, were confirmed by qRT-PCR. Numerous single nucleotide polymorphisms were also identified, providing a valuable resource for research and molecular marker-assistant breeding in Chinese cabbage. These results contribute to our understanding of the molecular regulatory mechanisms underlying growth and development and lay the foundation for future genetic and functional genomics studies in Chinese cabbage. The RNA from the third true leaves (day 15 to day 24 after the appearance of the third true leaves) of a developmentally retarded mutant (drm) and its wild type âFTâ in Chinese cabbage were sequenced by RNA-Seq, in triplicate.
Project description:The transition from vegetative growth to reproductive growth involves many pathways. Vernalization is crucial to the formation of floral organs, the regulation of flowering time and plant breeding. The purpose of this study was to identify the mRNA, microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) related to vernalization of Chinese cabbage, and to construct a competitive endogenous RNA (ceRNA) network, so as to provide valuable information for exploring the molecular mechanism of vernalization of Chinese cabbage. Results: The results of whole-transcriptome sequencing showed that 2702 mRNAs, 151 lncRNAs, 16 circRNA, and 233 miRNAs were differentially expressed in vernalized (‘Ver’) and non-vernalized (‘Nor’) seeds of Chinese cabbage. Some transcription factors and regulatory proteins that play important roles in vernalization pathway have been identified, such as the transcription factors of WRKY, MYB, NAC, bHLH, and MADS-box, zinc finger protein CONSTANS like gene and B3 domain protein. We constructed vernalization-related ceRNA-miRNA-target gene network and obtained 199 pairs of ceRNA relationships, including 108 DEmiRNA-DEmRNA, 67 DEmiRNA-DElncRNA, and 12 DEmiRNA-DEcircRNA interactions in Chinese cabbage. Meanwhile, several important vernalization-related genes and their interacting lncRNAs, circRNAs, and miRNAs were identified, which were involved in the regulation of flowering time, floral organ formation, bolting and flowering. Conclusions: The candidate differentially expressed mRNA, miRNA, lncRNA and circRNA for vernalization of Chinese cabbage were identified by the whole-transcriptome sequencing, and the ceRNA network was constructed. This study laid a foundation for further study on the molecular mechanism of vernalization in Chinese cabbage.
Project description:The transition from vegetative growth to reproductive growth involves many pathways. Vernalization is crucial to the formation of floral organs, the regulation of flowering time and plant breeding. The purpose of this study was to identify the mRNA, microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) related to vernalization of Chinese cabbage, and to construct a competitive endogenous RNA (ceRNA) network, so as to provide valuable information for exploring the molecular mechanism of vernalization of Chinese cabbage. Results: The results of whole-transcriptome sequencing showed that 2702 mRNAs, 151 lncRNAs, 16 circRNA, and 233 miRNAs were differentially expressed in vernalized (‘Ver’) and non-vernalized (‘Nor’) seeds of Chinese cabbage. Some transcription factors and regulatory proteins that play important roles in vernalization pathway have been identified, such as the transcription factors of WRKY, MYB, NAC, bHLH, and MADS-box, zinc finger protein CONSTANS like gene and B3 domain protein. We constructed vernalization-related ceRNA-miRNA-target gene network and obtained 199 pairs of ceRNA relationships, including 108 DEmiRNA-DEmRNA, 67 DEmiRNA-DElncRNA, and 12 DEmiRNA-DEcircRNA interactions in Chinese cabbage. Meanwhile, several important vernalization-related genes and their interacting lncRNAs, circRNAs, and miRNAs were identified, which were involved in the regulation of flowering time, floral organ formation, bolting and flowering. Conclusions: The candidate differentially expressed mRNA, miRNA, lncRNA and circRNA for vernalization of Chinese cabbage were identified by the whole-transcriptome sequencing, and the ceRNA network was constructed. This study laid a foundation for further study on the molecular mechanism of vernalization in Chinese cabbage.