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This study reported the first-ever de novo transcriptome analysis of Operculina turpethum, a high valued endangered medicinal plant, using the Illumina HiSeq 2500 platform. The de novo assembly generated a total of 64,259 unigenes and 20,870 CDS (coding sequence) with a mean length of 449 bp and 571 bp respectively. Further, 20,218 and 16,458 unigenes showed significant similarity with identified proteins of NR (non-redundant) and UniProt database respectively. The homology search carried out against publicly available database found the best match with Ipomoea nil sequences (82.6%). The KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis identified 6538 unigenes functionally assigned to 378 modules with phenylpropanoid biosynthesis pathway as the most enriched among the secondary metabolite biosynthesis pathway followed by terpenoid biosynthesis. A total of 17,444 DEGs were identified among which majority of the DEGs (Differentially Expressed Gene) involved in secondary metabolite biosynthesis were found to be significantly upregulated in stem as compared to root tissues. The qRT-PCR validation of 9 unigenes involved in phenylpropanoid and terpenoid biosynthesis also showed a similar expression pattern. This finding suggests that stem tissues, rather than root tissues, could be used to prevent uprooting of O. turpethum in the wild, paving the way for the plant's effective conservation. Moreover, the study formed a valuable repository of genetic information which will provide a baseline for further molecular research.

Operculina turpethum (L.) Silva Manso (Nisoth), an important medicinal plant whose root and stem tissues are found to be key ingredient in more than 135 herbal formulation in both Unani and Ayurvedic medicine system and is used for the treatment of various health disorders. It has a very high demand in the Indian Pharmaceutical industry with an annual average consumption of about 660 metric tonne (dry weight). The plant because of its wide usability is also exported to countries like Sri Lanka, Singapore, Netherlands, Japan, United States, etc. leading to a total export value of approximately 2.4 million USD. Terpenoids, steroid glycosides, resin glycosides, dammarane type triterpenoid saponins, flavonoids, coumarins are the major bioactive principles present in O. turpethum. However, overexploitation of root/root bark over the other part of the plant has caused depletion of its germplasm resources from the wild while bringing it to Near Threatened category which subsequently lead to unavailability of the requisite plant material followed by adulteration. Additionally, the limited genomics and transcriptomic resource is a major hindrance in the genetic and molecular research including elucidation of biosynthetic pathway, identification of enhanced traits and proper authentication and genetic diversity study of the plant. Hence, de novo transcriptome sequencing of root and stem tissues of O. turpethum was performed using Illumina HiSeq platform which generated a total of 64259 unigenes and 20870 CDS (coding sequence) with a mean length of 449bp and 571bp respectively. Further, 20218 and 16458 unigenes showed significant similarity with the identified proteins of NR(non-redundant) and Uniprot database respectively. The homology search carried out against publicly available database found the best match with Ipomoea nil sequences (82.6%). The KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis identified 6538 unigenes functionally assigned to 378 modules with phenylpropanoid biosynthesis pathway as the most enriched among the secondary metabolite biosynthesis pathway followed by terpenoid biosynthesis. Moreover, transcription factors, SSRs (Simple sequence repeats) and SNPs (single nucleotide polymorphism) were also identified in this study. Apparently, the present investigation reported the first ever transcriptome analysis of the root and stem tissues of the non-model plant O. turpethum of family Convolvulaceae, which will provide a baseline for further molecular research.

Background Caspase-8, a member of the family of conserved cysteine proteases, plays a crucial role in the initiation phase of the apoptotic death-signaling cascade and thereby attracts interest for its study across the animal species including fish. In India, rohu (Labeo rohita) is an important freshwater fish species; thus, this study on caspase-8 was undertaken to investigate its role during pathogenic invasion. Results The complete cDNA sequence of Labeo rohita caspase-8 (Lrcasp8) consisted of 1746 bp nucleotides (nt) having an ORF of 1440 nt encoding a polypeptide of 480 amino acid (aa) residues with the molecular mass of ∼ 54.8 kDa. Structurally, Lrcasp8 comprised two DED domains (DED11-77aa and DED297-174aa) and one CASc domain230-476aa. Within the CASc domain, various putative motifs, viz., a large subunit (p20237-360aa), a small subunit (p10389-474aa), and a penta-peptide (QACQG354-358aa) active site, were identified. The secondary structure of Lrcasp8 protein comprised seventeen α-helices, eleven β-strands, and twenty-nine coils. Phylogenetically, it is closely related to common carp caspase-8 and exhibits significant (p < 0.05) similarity (88.3%) and identity (78.7 %) in their amino acid sequence. The tissue-specific expression of Lrcasp8 has been analyzed by quantitative real-time PCR assay, and it revealed the highest expression (~ 23-fold) in the blood and lowest in the spleen. In Aeromonas hydrophila and Edwardsiella tarda infection and rhabdovirus vaccination, caspase-8 gene expression in rohu fingerlings was significantly (p Labeo rohita gill cells with A. hydrophila resulted in apoptosis and cell death with the induction of caspase-8 gene expression. Conclusion This is the first report on the identification and structural characterization of caspase-8 cDNA and predicted protein and the analysis of caspase-8 gene expression in Labeo rohita following Aeromonas hydrophila and Edwardsiella tarda infections and rhabdovirus vaccinations. The data in this article together suggest the critical role of caspase-8 during infection and apoptosis in Labeo rohita.

Celastrus paniculatus willd., an extremely versatile medicinal plant, is commonly used as memory sharpener, anti-depressant, rejuvenant, nervine tonic, free radical scavenger, anti-oxidant etc. The present review is made to enlighten the information based upon scientific evidence regarding morphological description, pharmacological actions and phytoconstituents of this plant. The leaves of the plant show significant anti-fungal and anti-microbial activity. The root bark exhibited antimalarial activity while seed shows sedative, antidepressant, antifertility and wound healing activity. These plants are naturally used for treatment of blood purification after delivery, menstruation cycle and abortion. Due to the wide range of medicinal properties, the plant is being harvested erratically from wild coupled with cultivars; the species is listed as endangered and a vulnerable medicinal plant. Hence, realising the importance of the plant and the current threat to its existence, more scientific effort is required for conservation and efficient propagation for this plant to meet the growing demand.

Among various caspases, caspase-9 plays a crucial role in the initiation phase of apoptotic cascade. To investigate about it in a high-valued freshwater fish species rohu (Labeo rohita), we cloned and characterized full-length caspase-9 cDNA (Lrcasp9) and analyzed its expression following bacterial infections and anti-viral vaccinations. The Lrcasp9 consisted of 1619-bp nucleotides (nt) having an ORF of 1302 nt encoding a polypeptide of 433 amino acids (aa) with a molecular mass of ∼ 48.20 kDa. Structurally, Lrcasp9 comprised of one CARD domain (1–89 aa) and one CASc domain (161–430 aa). The CASc domain consisted of one large subunit (p20) spanning from 168 to 300 aa, and a small sub unit (p10) from 343 to 430 aa. The caspase family signature histidine active motif H(233)SAYDCCVVIILSHG(247), cysteine active motif K(287)PKLFFIQACGG(298) and pentapeptide “QACGG” active sites present in the p20 domain of Lrcasp9 was conserved across fish species, mouse and human caspase-9. Phylogenetically, it was closely related to common carp caspase-9 and exhibited significant similarity (90.1%) and identity (85.3%) in their amino acid sequence. In the uninfected fish, Lrcasp9 gene expression was highest (~ 5.3-fold) in blood and lowest in gill. In response to Aeromonas hydrophila and Edwardsiella tarda infection and rhabdoviral vaccination, Lrcasp9 gene expression was significantly (p > 0.05) enhanced in gill, liver, kidney and spleen, and also in vitro during cell death, suggesting activation of the intrinsic apoptotic pathway in bacterial infections and anti-viral vaccination in Labeo rohita.