Project description:MicroRNAs (miRNAs) are essential small RNA molecules that regulate the expression of target mRNAs in plants and animals. Here, we aimed to identify miRNAs and their putative targets in Hibiscus syriacus, the national flower of South Korea. Therefore, we employed high-throughput sequencing of small RNAs obtained from four different tissues (i.e., leaf, root, flower, and ovary) and identified 33 conserved and 30 novel miRNA families, many of which showed differential tissue-specific expressions. In addition, we computationally predicted novel targets of miRNAs and validated some of them using 5′ rapid amplification of cDNA ends analysis. One of the validated novel targets of miR477 was a terpene synthase, the primary gene involved in the formation of disease-resistant terpene metabolites such as sterols and phytoalexins. In addition, a predicted target of conserved miRNAs, miR396, is SHORT VEGETATIVE PHASE, which is involved in flower initiation and is duplicated in Hibiscus syriacus. Collectively, this study provides the first reliable draft of the Hibiscus syriacus miRNA transcriptome that should constitute a basis for understanding the biological roles of miRNAs in Hibiscus syriacus.
2017-09-08 | GSE99329 | GEO
Project description:Terpene synthase gene amplicons from subseafloor sediments
Project description:In Crohn's disease, creeping fat is the characteristic expansion of mesenteric adipose tissue wrapping around the inflamed intestine. Through a comparative transcriptomic analysis of creeping fat and normal-looking mesenteric adipose tissues from patients with Crohn's disease and non-Crohn's disease, we found that a dynamic transcriptional and cell compositional change occurs during the progression from non-Crohn's disease to Crohn's disease, and finally to creeping fat.
Project description:<p>Pogostemon cablin (Blanco) Benth. cv. 'Jing Huoxiang', is a valuable medicinal plant widely studied for its aboveground tissues, which are rich in bioactive compounds such as patchouli alcohol. However, systematic investigations into the biosynthesis of sesquiterpenes in its underground parts (roots) remain limited, with several critical knowledge gaps: (1) the metabolic basis of root-specific accumulation of polycyclic sesquiterpenes is unclear; (2) key terpene synthase (TPS) gene resources remain underexplored; and (3) the regulatory network of terpenoid biosynthesis is poorly understood. Addressing these questions is essential for the rational design and efficient production of terpene synthases.In this study, we integrated metabolomic and transcriptomic approaches to systematically characterize terpenoid profiles across different tissues of P. cablin and elucidate their biosynthetic regulation. Using GC-MS analysis, we identified distinct terpenoid compositions in roots, stems, leaves, flowers, and glandular trichomes. Notably, patchouli alcohol and pogostone accounted for over 60% of the total volatile oil content, while roots specifically accumulated polycyclic sesquiterpenes such as β-caryophyllene and α-humulene. Through transcriptome sequencing and bioinformatic analysis, we comprehensively annotated the TPS gene family, revealing that the TPS-a subfamily (34 genes) was the most abundant in P. cablin, with several members exhibiting root-predominant expression. Co-expression network analysis further identified candidate genes encoding potential high-efficiency polycyclic sesquiterpene synthases and uncovered a β-caryophyllene/α-humulene-regulated tertiary metabolic pathway.Our findings not only fill a critical gap in understanding sesquiterpene biosynthesis in the underground tissues of P. cablin but also provide a foundation for synthetic biology-based optimization of terpenoid production. This research paves the way for the efficient biosynthesis of sesquiterpenes to meet industrial demands in pharmaceuticals, fragrances, and biofuels.</p>
Project description:In order to characterize defense responses not only cytologically, but also on the transcript level, genome-wide sequencing of mRNA isolated from non-infected control leaves and from leaves inoculated either with the WT or with GLS1 overexpressing strains was performed, using Illumina Next Generation Sequencing Technology. In order to identify transcripts specifically induced in leaves infected by β-1,3-glucan-exposing strains, transcript patterns of leaves inoculated with GLS1 overexpressing PtrpC:GLS1 strains were compared with those of the WT. In PtrpC:GLS1-inoculated leaves, a total of 2179 genes were more than 2.5-fold increased, with many genes known as genes typically up-regulated in PAMP-triggered defense responses. These genes include genes encoding PR proteins enzymes involved in cell wall re-inforcemen, and terpene synthases possibly involved in phytoalexin synthesis. Furthermore, increased transcript abundance of genes encoding serine-threonine receptor-like kinases calmodulin, as well as zinc-finger and WRKY transcription factors have been identified. Other up-regulated genes encode proteins involved in protein degradation, i.e. proteases, ubiquitin ligases, as well as enzymes involved in synthesis of auxin or cytokinin phytohormones. In comparison, 2164 genes were more than 2.5-fold down-regulated in maize leaves infected by PtrpC:GLS1 strains, as compared to WT-infected leaves. Several of the encoded proteins are known susceptibility factors. Forty-six down-regulated genes code for proteins containing iron or manganese, or are involved in uptake of these ions, suggesting major re-arrangement of the redox-status in maize leaves after β-glucan perception.