Dataset on discovery of microRNAs in Centella asiatica (L.) Urb.

MicroRNAs (miRNAs) are small (21-24 nucleotides), non-coding, riboregulators that regulate gene expression in eukaryotes. Pentacyclic triterpenoid saponins and sapogenins known as centellosides of the plant Centella asiatica (L.) Urb. are known for their broad spectrum medicinal properties. Two C. asiatica accessions viz.,CA301 and CA308 were selected for the miRNAome profiling. Total RNA isolated from fresh young leaves of both accessions along with their replicas was used for library construction. Illumina® sequencing of the four small RNA libraries generated a total of 59,234,923; 58,487,817; 59,520,376; 64,093,228 raw reads. The raw reads were quality filtered and used for the prediction of conserved and novel miRNAs. A total of 227 conserved and 109 novel microRNAs were identified from the libraries. Target gene prediction done using psRNAtarget and PANTHER™GO helped in localization of predicted targets. KEGG (Kyoto Encyclopedia for Genes and Genomes) was used for pathway prediction of the targets of predicted miRNAs. The present study provides first elaborated glimpse of miRNA pool of C. asiatica. The outcome of this research could help understand miRNA dependent regulation of centelloside biosynthesis and to design further metabolic engineering experiments to enhance their content in this important medicinal plant.

Data on large cardamom transcriptome associated with Chirke disease.

Large cardamom (Amomum subulatum Roxburg), is an ancient spice native to North-Eastern India and Southeast Asia, which belongs to the family Zingiberaceae under the order Scitaminae. Large cardamom is mostly affected by a viral disease termed Chirke caused by Large Cardamom Chirke Virus (LCCV). These disease has spread due to drastic changes in the ecosystem, inadequate rain in dry months and absence of good agricultural practices by the farmers resulting in aphid infestations. In the present study, using HiSeq™ 2000 RNA sequencing technology transcriptome sequencing was performed for both control (disease not expressed) and diseased large cardamom leaf tissues. RNA-seq generated 77260968 (7.72 GB) and 72239708 (7.22 GB) paired raw reads for large cardamom control and diseased samples respectively. The raw data were submitted to the NCBI SRA database under the accession numbers SRX2529373 and SRX2529372 and the assembled transcriptomes were submitted to TSA under the accession numbers GIAV01000000 and GIAW01000000 for the control and diseased samples respectively. The raw reads were quality trimmed and assembled de novo using TRINITY assembler which created 156822 (control) and 148953 (diseased) contigs with N50 values 2107 (control) and 2182 (diseased). The data were used to identify the significantly differentially expressed genes between control and diseased samples.

Data on small cardamom transcriptome associated with capsule rot disease.

Small cardamom (Elettaria cardamomum (L.) Maton, also known as the 'Queen of Spices' is a rhizomatous herbaceous monocot from the family Zingiberaceae. In the present study, using HiSeq™ 2000 RNA sequencing technology, transcriptome sequencing was performed for both control and disease stressed small cardamom leaf tissues. RNA-seq generated 46,931,637 (101 base) and 31,682,496 (101 base) raw reads and totally 9.93GB and 6.63GB of sequence data for cardamom control and stressed samples respectively. The raw data were submitted to NCBI SRA database of under the accession numbers SRX2512359 and SRX2512358 for the control and diseased samples respectively. The raw reads were quality filtered and assembled using TRINITY de novo assembler which created 1,11,495 (control) and 91,096 (diseased) contigs with N50 values 3013 (control) and 2729 (stressed). The data was further used to identify significantly differentially expressed unigenes between control and stressed samples. Assembled unigenes were further annotated and evaluated in silico to predict the function using publicly available databases and gene annotation tools.

Deep sequencing identified potential miRNAs involved in defence response, stress and plant growth characteristics of wild genotypes of cardamom.

Cardamom has long been used as a food flavouring agent and in ayurvedic medicines for mouth ulcers, digestive problems and even depression. Extensive occurrence of pests and diseases adversely affect its cultivation and result in substantial reductions in total production and productivity. Numerous studies revealed the significant role of miRNAs in plant biotic stress responses. In the current study, miRNA profiling of cultivar and wild cardamom genotypes was performed using an Ion Proton sequencer. We identified 161 potential miRNAs representing 42 families, including monocot/tissue-specific and 14 novel miRNAs in both genotypes. Significant differences in miRNA family abundance between the libraries were observed in read frequencies. A total of 19 miRNAs (from known miRNAs) displayed a twofold difference in expression between wild and cultivar genotypes. We found 1168 unique potential targets for 40 known miRNA families in wild and 1025 potential targets for 42 known miRNA families in cultivar genotypes. The differential expression analysis revealed that most miRNAs identified were highly expressed in cultivars and, furthermore, lower expression of miR169 and higher expression of miR529 in wild cardamom proved evidence that wild genotypes have stronger drought stress tolerance and floral development than cultivars. Potential targets predicted for the newly identified miRNAs from the miRNA libraries of wild and cultivar cardamom genotypes involved in metabolic and developmental processes and in response to various stimuli. qRT-PCR confirmed miRNAs were differentially expressed between wild and cultivar genotypes. Furthermore, four target genes were validated experimentally to confirm miRNA-mRNA target pairing using RNA ligase-mediated 5' Rapid Amplification of cDNA Ends (5'RLM-RACE) PCR.

Piriformospora indica cell wall extract as the best elicitor for asiaticoside production in Centella asiatica (L.) Urban, evidenced by morphological, physiological and molecular analyses.

Vascular plants synthesise a multitude of organic molecules or phytochemicals, referred to as "secondary metabolites". These molecules are involved in a variety of roles in the life span of plants, ranging from structural ones to protection. Centella asiatica (L.) Urban has probably been used since prehistoric times and has been reported to have been used for various medicinal and cosmetic purposes. The plant contains several active constituents, of which the most important is asiaticoside, a triterpenoid. Asiaticoside content in C. asiatica can be enhanced by the use of biotic elicitors like Piriformospora indica. P. indica has been used as a model to study the mechanisms and evolution of mutualistic symbiosis. P. indica is similar to Arbuscular Mycorrhizal (AM) fungi in terms of plant growth promotional effects. The autoclaved fraction from P. indica (PiCWE) was found to be the most active fraction in promoting the plant biomass and asiaticoside content. To date, there are no reports on the potential role of PiCWE in enhancement of asiaticoside over the control and P. indica colonized plants, which was evidenced by the differential expression of key genes involved and final asiaticoside content along with the determination of phytohormones. Moreover, differential expression of selected miRNAs in PiCWE - C. asiatica root interactions over the control and P. indica treated C. asiatica leaf samples was also scrutinized. The important consequence of induction with PiCWE was the significant enhancement of asiaticoside in the PiCWE induced plants in comparison with the asiaticoside content in control and P. indica-C. asiatica interaction. In addition, the role of miRNAs in C. asiatica - PiCWE would enable more in-depth studies for deciphering the molecular and physiological mechanisms of the association and regulation of PiCWE - C. asiatica interactions.

Data on identification of conserved and novel miRNAs in Elettaria cardamomum.

Elettaria cardamomum (L.) Maton, or small cardamom referred as 'queen of spices', is a perennial herbaceous rhizomatous monocot of the family Zingiberaceae. Cardamom seeds and fruits are the economically significant parts and effectively used as a traditional medicine, food additive and flavoring agent. In the present study, using Ion Proton next generation sequencing technology we performed the small RNA sequencing, conserved and novel miRNA predictions of a wild and five cultivar genotypes of cardamom. Small RNA sequencing generated a total of 5,451,328 and 2,756,250 raw reads for wild and cultivar cardamom respectively. The raw data was submitted to SRA database of NCBI under the accession numbers and SRX2273863 (wild) and SRX2273862 (cultivars). The raw reads were quality filtered and predicted conserved and novel miRNAs for wild and cultivar cardamom. The predicted miRNAs, miRNA-targets and functional annotations might provide valuable insights into differences between wild progenitor and cultivated cardamom.

Transcriptome profiling of Elettaria cardamomum (L.) Maton (small cardamom).

Elettaria cardamomum (L.) Maton, known as 'queen of spices, is a perennial herbaceous monocot of the family Zingiberaceae, native to southern India. Cardamom is an economically valuable spice crop and used widely in culinary and medicinal purposes. In the present study, using Ion Proton RNA sequencing technology, we performed transcriptome sequencing and de novo transcriptome assembly of a wild and five cultivar genotypes of cardamom. RNA-seq generated a total of 22,811,983 (92 base) and 24,889,197 (75 base) raw reads accounting for approximately 8.21GB and 7.65GB of sequence data for wild and cultivar genotypes of cardamom respectively. The raw data were submitted to SRA database of NCBI under the accession numbers SRX1141272 (wild) and SRX1141276 (cultivars). The raw reads were quality filtered and assembled using MIRA assembler resulted with 112,208 and 264,161contigs having N50 value 616 and 664 for wild and cultivar cardamom respectively. The assembled unigenes were functionally annotated using several databases including PlantCyc for pathway annotation. This work represents the first report on cardamom transcriptome sequencing. In order to generate a comprehensive reference transcriptome, we further assembled the raw reads of wild and cultivar genotypes which might enrich the plant transcriptome database and trigger advanced research in cardamom genomics.

MiRNA Isolation from Plants Rich in Polysaccharides and Polyphenols.

MicroRNAs (miRNAs) are a group of 18-22-nucleotide-long noncoding RNAs, which show wide array of roles in various biological and metabolic processes in both animals and plants. They are formed endogenously and have evolutionary conserved sequences. RNA quality is extremely important for sequencing miRNAs using next-generation sequencing platforms. However, isolation and quantification of miRNAs from plant samples are often technically difficult and recovery of miRNAs from total RNA might be problematic. Degradation of RNA weakens the true miRNAs present in the sample, hence it is crucial to use a protocol that effectively retains good integrity miRNAs. In this chapter, we outline few protocols that can be used to maximize the retrieval of good-quality miRNA and total RNA to be used in miRNA analysis for plants rich in polysaccharides and polyphenols.

Intraspecific variations in cardamom (Elettaria cardamomum Maton): assessment of genomic diversity by flow cytometry, cytological studies and ISSR analysis.

BACKGROUND: The main goal of the work was to analyse intraspecific variation in Elettaria cardamomum Maton (cardamom) using genome size, cytological studies and molecular marker data. Nuclear DNA content and molecular marker details furnish data on genome size and genetic diversity respectively among the studied accessions and both complement each other for evolutionary and taxonomic studies. RESULTS: The relative 2C genome size and total number of base pairs of cardamom was determined through flow cytometric analysis using propidium iodide staining. The nuclear DNA content was estimated in various sections of the species representing individuals from wild and cultivar genotypes following Zea mays L. CE-777 (2C = 5.43 pg) as internal reference standard. Chromosome number from growing root tip was examined following standard protocols. Twenty-six ISSR primers that generated polymorphic bands were used for genetic diversity analysis of the thirty accessions of cardamom. Estimated nuclear 2C DNA content ranged from 2.57 to 3.22 pg demonstrating 1.25-fold variation. The mean amount of 2C nuclear DNA of the cardamom was calculated as 2.87 pg which is equivalent of 2806 Mbp as the diploid genome size. The chromosome number was found to be 2n = 48. Among the thirty accessions of cardamom studied using ISSR markers, C53 (feral from Bonacaud) showed a very prominent level of genetic diversity and was lowest for C96 (Avinash-I, a released variety from Indian Institute of Spices Research, Kozhikode). CONCLUSION: These analyses revealed the existence of genetic variability within the studied cardamom accessions. The plant specimens also differed significantly in their genome size. However, the genetic variability parameters did not show any correlation with genome size.

Identification of quantitative trait loci for blast resistance in BC2F3 and BC2F5 advanced backcross families of rice.

Advanced backcross families derived from Oryza sativa cv MR219/O. rufipogon IRGC105491 were utilized for identification of quantitative trait loci (QTL) for blast resistance using simple sequence repeat markers. Two hundred and sixty-one BC(2)F(3) families were used to construct a linkage map, using 87 markers, which covered 2375.2 cM of 12 rice chromosomes, with a mean density of 27.3 cM. The families were evaluated in a greenhouse for resistance to blast disease caused by pathotypes P7.2 and P5.0 of Magnaporthe oryzae. Five QTLs (qBL5.1, qBL5.2, qBL6.1, qBL8.1, and qBL10.1) for pathotype P5.0 and four QTLs (qBL5.3, qBL5.4, qBL7.1, and qBL8.2) for pathotype P7.2 were identified using the BC(2)F(3) families. Another linkage map was also constructed based on 31 BC(2)F(5) families, using 63 SSR markers, which covered 474.9 cM of 9 rice chromosomes, with a mean density of 8.01 cM. Five suggestive QTLs (qBL11.2, qBL11.3, qBL12.1, qBL12.2, qBL12.3) and one putative QTL (qBL2.1) were identified for pathotype P7.2. Also, seven suggestive QTLs (qBL1.1, qBL2.2, qBL4.1, qBL4.2, qBL5.3, qBL8.3, and qBL11.1) were detected for pathotype P5.0. We conclude that there is a non-race-specific resistance spectrum of O. rufipogon against M. oryzae pathotypes.