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Overexpression of a novel geranylgeranyl pyrophosphate synthase gene (WsGGPPS) in planta resulted in increased levels of gibberellic acid and decrease in withanolide content. Withania somnifera (L.) Dunal, the herb from family Solanaceae is one of the most treasured medicinal plant used in traditional medicinal systems owing to its unique stockpile of pharmaceutically active secondary metabolites. Phytochemical and pharmacological studies in this plant were well established, but the genes affecting the regulation of biosynthesis of major metabolites were not well elucidated. In this study cloning and functional characterization of a key enzyme in terpenoid biosynthetic pathway viz. geranylgeranyl pyrophosphate synthase (EC 2.5.1.29) gene from Withania somnifera was performed. The full length WsGGPPS gene contained 1,104 base pairs that encode a polypeptide of 365 amino acids. The quantitative expression analysis suggested that WsGGPPS transcripts were expressed maximally in flower tissues followed by berry tissues. The expression levels of WsGGPPS were found to be regulated by methyl jasmonate (MeJA) and salicylic acid (SA). Amino acid sequence alignment and phylogenetic studies suggested that WsGGPPS had close similarities with GGPPS of Solanum tuberosum and Solanum pennellii. The structural analysis provided basic information about three dimensional features and physicochemical parameters of WsGGPPS protein. Overexpression of WsGGPPS in planta for its functional characterization suggested that the WsGGPPS was involved in gibberellic acid biosynthesis.

In any educational system there are broadly speaking, five clearly defined components. They are: (1) students, their needs and expectations; (2) teachers, their competencies and commitment; (3) infrastructure which includes buildings, libraries, laboratories and classrooms; and (4) syllabi of courses, their framing and execution; and (5) most importantly a clearly conceived and unambiguously stated objective. Detailed discussions on the theoretical aspects of these components can go on ad infinitum. In order to make our discussions meaningful and relevant, it will, of course, be desirable to read our analysis of the related issues in the context of our own situation in the country. It will not be an exaggeration to assert that the area which attracted the least serious attention of those responsible for the governance of our educational system during the post-independence period is education. We may gloat over the unbridled proliferation of educational institutions and explosion of student-population flocking to these institutions. But the big question remains and that is whether our educational system as a whole is founded on any definite objective which alone can provide a sustainable direction. Flexibility in objectives is understandable but a radical deviation from the age-old purpose of liberal education meant for shaping humans into a worthwhile creation of God can only prove disastrous. Education should aim at primarily developing students' personality and chiselling those inherent traits in him with which he is born in God's own image. This assertion may sound too holistic to utilitarian ears. But it has stood the test of time since humanity came into existence

Queues can be seen as a service facility where quality of service (QoS) is an important measure for the performance of the system. In many cases, the queue implements the optimal admission control (either discounted or average) policy in the presence of holding/congestion cost and revenue collected from admitted customers. In this paper, users offer an arrival rate at stationarity that depends on the QoS they experience. We study the interaction between arriving customers and such a queue under two different QoS measures—the asymptotic rate of the customers lost and the fraction of customers lost in the long run. In particular, we investigate the behaviour of equilibrium points and equilibrium sets associated with this interaction and their interpretations in terms of business cycles. We provide sufficient conditions for existence of equilibrium sets for M/M/1 queue. These conditions further help us to identify the relationship among system parameters for which equilibrium sets exist. Next, we consider $$\textit{GI}/M/1$$ queues and provide a sufficient condition for existence of multiple optimal revenue policies. We then specialize these results to study the equilibrium sets of (i) a D/M/1 queue and (ii) a queue where the arrival rate is locally continuous. The equilibrium behaviour in the latter case is more interesting as there may be multiple equilibrium points or sets. Motivated by such queues, we introduce a weaker version of monotonicity and investigate the existence of generalized equilibrium sets.

W.B. Yeats is a poet of great artistic honesty and integrity. In his critical statements he has candidly stated his artistic intentions and preoccupations. For such students of Yeats as have been puzzled by the artistic intentions of the poet in regard to the subject matter of his poetry, he has clarified his stance in his cryptic remark, “I remake myself” in my poetic compositions. Yeats, as every scholar knows it, is paradoxically a very complex and a simple poet. His complexity lies in his reader’s bewilderment at the contradictory artistic issues and his simplicity lies in its being a key to the unlocking of some of the ambiguities lurking in some of his poems. In his poetry, sometime he raises an issue which develops logically but the conclusion seems to stultify his explicit poetic statement, because the conclusion of the poem is deliberately made meaningfully ambiguous. His “Sailing to Byzantium” is a poem of this type of complex simplicity.

Sean O'Casey came in the limelight with his Dublin Trilogy of which the first play, named, The shadow of a gunman, was premiered at the Abbey in 1923. But he had earlier written three plays- The Frost in the Flower (1917), The Harvest Festival (1918) and The Crimson in the Tricolor (1920)- which were rejected by the Abbey directorate. Of these the first and the last named above are still untraceable and it is "unlikely that either will ever be recovered now."1 However, Luckily the manuscript of The Harvest Festival was acquired by the Berg Collection of the New York Public Library in 1969 and was not available to scholars until 1978. Robert Patrick Murphy has said, "I have not been able to examine. The Harvest Festival. Lola L. Szladits, Curator of the Berg collection of the New York Public Library, considers the holograph a 'museum piece' and maintains an official policy of discouraging access by students."2 it was first published in America in 1978 and in Ireland and Britain in 19809. It is logical, therefore, that no study on the play could be made until this time, though references to it do occur in a number of book- length studies on O'Casey's plays. But even these stray remarks on the play are made on the basis of what O'Casey himself has to say about it in his Innisfallen Fare thee Well,3 and not on that on any close reading of the text. It is pertinent to notice that even seventeen years after its publication the play is yet to be performed. During his life time O'Casey himself showed no interest in the play in his writings and correspondence; his venture to revise the play remained incomplete; only the first Act is partly revised John O'Riordan has regretted: "The dramatist himself in his meridian years never strove to promote it."4 Even the O'Casey Annual and Sean O'Casey's Review, two major journals aiming at promoting fresh studies and researches on the unexplored areas of O'Casey's writings, have shown singular neglect of this play. Perhaps, drawing a clue from the dramatist himself, some of the major O'Casey scholars in their studies have disparaged the play.

Withania somnifera (Ashwagandha) is considered as Rasayana in Indian systems of medicine. This study reports a novel transcriptome of W. somnifera berries, with high depth, quality and coverage. Assembled and annotated transcripts for nearly all genes related with the withanolide biosynthetic pathway were obtained. Tissue-wide gene expression analysis reflected almost similar definitions for the terpenoid pathway in leaf, root and berry tissues with relatively higher abundance of transcripts linked to steroid, phenylpropanoid metabolism as well as flavonoid metabolism in berries. The metabolome map generated from the data embodied transcripts from 143 metabolic pathways connected together and mediated collectively by about 1792 unique enzyme functions specific to berry, leaf and root tissues, respectively. Transcripts specific to cytochrome p450 (CYP450), methyltransferases and glycosyltransferases were distinctively located in a tissue specific manner and exhibited a complex network. Significant distribution of transcription factor genes such as MYB, early light inducible protein (ELI), minichromosome maintenance1, agamous, deficiens and serum response factor (MADS) and WRKY etc. was observed, as the major transcriptional regulators of secondary metabolism. Validation of the assembly was ascertained by cloning WsELI, which has a light dependent regulatory role in development. Quantitative expression of WsELI was observed to be considerably modulated upon exposure to abiotic stress and elicitors. Co-relation of over-expression of WsELI, may provide new aspects for the functional role of ELI proteins in plants linked to secondary metabolism. The study offers the first comprehensive and comparative evaluation of W. somnifera transcriptome data between the three tissues and across other members of Solanaceae (Nicotiana, Solanum and Capsicum) with respect to major pathways and their metabolome regulation.

Analysis of autophagy-related genes in tomato shows the involvement of SlATG18f in leaf curl disease tolerance and a CAPS marker developed from this gene demonstrates its usefulness in marker-assisted selection. Autophagy is a highly conserved catabolic process regulating cellular homeostasis and adaptation to different biotic and abiotic stress. Several autophagy-related proteins (ATGs) are reported to be involved in autophagic processes, and considering their importance in regulating growth and stress adaptation, these proteins have been identified and characterized in several plant species. However, there is no information available on the role of autophagy-related proteins regulating the tolerance of tomato to tomato leaf curl disease (ToLCD). Given this, the present genome-wide study identified thirty ATG-encoding genes (SlATG) in tomato, followed by their functional characterization. Expression profiling of the SlATG genes in contrasting tomato cultivars subjected to virus infection showed a 4.5-fold upregulation of SlATG18f in the tolerant cultivar. Further, virus-induced gene silencing of SlATG18f in the tolerant cultivar conferred disease susceptibility, which suggested the role of this gene in Tomato leaf curl New Delhi virus tolerance. Comparison of the gene sequence of both tolerant and susceptible cultivars along with the 5′ upstream regions identified an SNP (A/T) at -2916 upstream of the start codon. A cleaved amplified polymorphic sequence (CAPS) marker was developed targeting this region, which showed a significant association with the tolerance characteristics in the tomato germplasm (R2 = 0.1787). Altogether, the study identified a potential gene that could be used to develop ToLCNDV tolerant tomato cultivars using transgene-based or marker-assisted breeding-based approaches.

Transcription factors (TFs) are important regulators of cellular and metabolic functions including secondary metabolism. Deep and intensive RNA-seq analysis of Withania somnifera using transcriptomic databases provided 3532 annotated transcripts of transcription factors in leaf and root tissues, belonging to 90 different families with major abundance for WD-repeat (174 and 165 transcripts) and WRKY (93 and 80 transcripts) in root and leaf tissues respectively, followed by that of MYB, BHLH and AP2-ERF. Their detailed comparative analysis with Arabidopsis thaliana, Capsicum annum, Nicotiana tabacum and Solanum lycopersicum counterparts together gave interesting patterns. However, no homologs for WsWDR representatives, LWD1 and WUSCHEL, were observed in other Solanaceae species. The data extracted from the sequence read archives (SRA) in public domain databases were subjected to re-annotation, re-mining, re-analysis and validation for dominant occurrence of WRKY and WD-repeat (WDR) gene families. Expression of recombinant LWD1 and WUSCHEL proteins in homologous system led to enhancements in withanolide content indicating their regulatory role in planta in the biosynthesis. Contrasting expression profiles of WsLWD1 and WsWUSCHEL provided tissue-specific insights for their participation in the regulation of developmental processes. The in-depth analysis provided first full-spectrum and comparative characteristics of TF-transcripts across plant species, in the perspective of integrated tissue-specific regulation of metabolic processes including specialized metabolism.

We consider the problem of learning linear classifiers when both features and labels are binary. In addition, the features are noisy, i.e., they could be flipped with an unknown probability. In Sy-De attribute noise model, where all features could be noisy together with same probability, we show that 0-1 loss (l0−1) need not be robust but a popular surrogate, squared loss (lsq) is. In Asy-In attribute noise model, we prove that l0−1 is robust for any distribution over 2 dimensional feature space. However, due to computational intractability of l0−1, we resort to lsq and observe that it need not be Asy-In noise robust. Our empirical results support Sy-De robustness of squared loss for low to moderate noise rates.

Withania somnifera owing to its strong and remarkable stress tolerance property is a reliable candidate for the determination of genes involved in mechanism of adaption/tolerance of various stress conditions. 187 AP2/ERF gene related transcripts (GRTs) were identified during comprehensive search in W. somnifera transcriptome repertoire. Major hits in homology search were observed from the model plant Arabidopsis and members of Solanaceae family. Cloning, expression analysis of the gene and genetic transient transformation with the gene (WsAP2) were performed to predict its functional role in planta. Enhanced expression of some of the pathway genes for terpenoid biosynthesis was observed in transformed tissues in comparison to the control tissues. It is speculated that WsAP2 gene crucially regulates the expression of GGPPS gene in addition to the regulation of other important genes of terpenoid pathway via induction of expression of other genes such as HMGR, CAS, DXS and DXR. To the best of our knowledge, this is the first report representing detailed study of AP2/ERF gene family in W. somnifera. It is also suggested from the study that gene might have role in eliciting responses to combat stress and attribute the strong stress tolerant property associated with the plant.

Medicinal plants are the vital source of numerous structurally diverse pharmacologically active metabolites collectively called as secondary metabolites finding extensive applications in traditional systems of medicine and in pharmaceutical industries. Several distinctive and complex pathways operate in an interactive manner via metabolic networks that are responsible for the accumulation of such highly specialized metabolites. Secondary metabolites are believed to play a wide spectrum of physiological and functional roles in plants, many of which being investigated and supported by the experimental studies. Biosynthetic pathway related studies on various aspects in these medicinal plants have been found very tedious owing to several issues in plants such as considerably lower metabolite concentrations in native tissues, existence at different locations, and highly complex multi-step pathways, etc. Pathway elucidation and gene/enzyme discovery for studying metabolic pathway evolution and subsequent engineering could be better achieved by mining various pathway databases and reconstruction of metabolic networks available at different omics databases. Though medicinal plants have a limited range of genomic sequences available, however recently, next generation sequencing is being widely used to generate a comprehensive transcriptomic resource for these plants. It is anticipated that databases and resources generated from these studies are likely to play a key role towards the study and exploitation of metabolites from medicinal plants in near future. In this review, we have discussed next generation sequencing approaches, which were used for the generation of transcriptomic resources for several medicinally important plants. The relevance of transcriptomic approaches in curation of the pathways linked with the synthesis of major secondary metabolites along with their precursors of pharmaceutical importance in medicinal plants is also comprehensively analysed.

We first propose an empirical risk minimization based binary classification algorithm, ExpERM, with exponential function as surrogate loss function. Our ExpERM algorithm is scalable in both the dimension of feature space as well as in the number of data points as it is an unconstrained differentiable convex optimization problem or a convex optimization problem with a single constraint in the regularized ExpERM framework. Under mild assumption on data, we show that ExpERM classifier is unique. We implement ExpERM on wide collection (large-features, large-examples) of real datasets. We use Wilcoxon signed-rank test to show that these easily computable classifiers have good generalization property as their 5 or 10-fold cross validation error is not significantly different from those classifiers obtained by standard hinge loss based SVMs or AdaBoost classifiers. Using some large feature sized datasets, we make a statistical comparison of SVM and ExpERM and observe that ExpERM takes remarkably less time to train the model. Towards better understanding this simple and effective learning algorithm, we obtain PAC like sample complexity bounds for regularized ExpERM and high probability bounds for ExpERM based on Rademacher complexity and uniform stability notions. Our computational experience suggests that the regularization does not significantly improve the performance of the ExpERM based classifier. Due to repeated calls to be made to the binary classifier routines in implementation of combined multi-class algorithms, ExpERM scheme is expected to be significantly computationally cheaper and hence scalable. We statistically show that CV error of our binary ExpERM classifiers on many multi-class datasets is comparable to those obtained using computationally expensive binary class SVMs.

Plants are the natural source of innumerable chemicals which are synthesized via integrated complex networking biosynthetic pathways. We are dependent on plants for our needs since ancient time, and their population still seems enough for fulfilling our demands, but when we see in near future we are forced to think about the availability of resources for our next-generations, then we start to search for another alternative options of resources about food/food supplement, medicines and other required items. For accomplishing this task we are opting plant metabolic engineering by which we can produce higher amount of products in least time and less space. Metabolic engineering is the term giving a concept of alteration in metabolomics of any organism by regulating biosynthetic mechanism through reconstitution of changes at genetic level. Aim of metabolic engineering is enhancement of desired product through upregulation of some gene or may be through down regulation of other genes. It can be performed in either native system or any other heterologous system. Plant metabolic engineering needs knowledge about molecular biology techniques such as isolation and cloning of gene(s), and then its transformation in other suitable systems. By using plant metabolic engineering approach, tremendous changes at metabolic level in different plants have been done. In addition to basic techniques, systems biology approach seems to be more helpful by cutting some unnecessary exercise at wet lab level. By using bioinformatics tools, we can easily refine our targets (genes/enzymes) for application in metabolic engineering process. After a decade of research in this field still we are not at satisfactory status regarding the products development. We have to go many more steps ahead for attaining satisfactory achievements. Slow but steady progress in this area will soon result into a miracle growth and produce solution for all globally challenged problems.

Cytochrome P450s (CYPs) catalyse a wide variety of oxygenation/hydroxylation reactions that facilitate diverse metabolic functions in plants. Specific CYP families are essential for the biosynthesis of species-specialized metabolites. Therefore, we investigated the role of different CYPs related to secondary metabolism in Withania somnifera, a medicinally important plant of the Indian subcontinent. In this study, complete complementary DNAs (cDNAs) of four different CYP genes were isolated and christened as WSCYP93Id, WSCYP93Sm, WSCYP734B and WSCYP734R. These cDNAs encoded polypeptides comprising of 498, 496, 522 and 550 amino acid residues with their deduced molecular mass of 56.7, 56.9, 59.4 and 62.2 kDa, respectively. Phylogenetic study and molecular modelling analysis of the four cloned WSCYPs revealed their categorization into two CYP families (CYP83B1 and CYP734A1) belonging to CYP71 and CYP72 clans, respectively. BLASTp searches showed similarity of 75 and 56 %, respectively, between the two CYP members of CYP83B1 and CYP734A1 with major variances exhibited in their N-terminal regions. The two pairs of homologues exhibited differential expression profiles in the leaf tissues of selected chemotypes of W. somnifera as well as in response to treatments such as methyl jasmonate, wounding, light and auxin. Light and auxin regulated two pairs of WSCYP homologues in a developing seedling in an interesting differential manner. Their lesser resemblance and homology with other CYP sequences suggested these genes to be more specialized and distinct ones. The results on chemotype-specific expression patterns of the four genes strongly suggested their key/specialized involvement of the CYPs in the biosynthesis of chemotype-specific metabolites, though their further biochemical characterization would reveal the specificity in more detail. It is revealed that WSCYP93Id and WSCYP93Sm may be broadly involved in the oxygenation reactions in the plant and, thereby, control various pathways involving such metabolic reactions in the plant. As a representative experimental validation of this notion, WSCYP93Id was heterologouly expressed in Escherichia coli and catalytic capabilities of the recombinant WSCYP93Id protein were evaluated using withanolides as substrates. Optimized assays with some major withanolides (withanone, withaferin A and withanolide A) involving spectrophotometric as well as high-pressure liquid chromatography (HPLC)-based evaluation (product detection) of the reactions showed conversion of withaferin A to a hydroxylated product. The genes belonging to other CYP group are possibly involved in some specialised synthesis such as that of brassinosteroids.

Withania somnifera due to its characteristic secondary metabolite content is of valuable medicinal significance and thus various omics approaches have been recently gaining lots of interest. Present updates had revealed various key enzymes involved in withanolide biosynthetic pathway. Molecular markers (SSRs) resources have also been established and have provided leads to study intra and inter-specific gene diversity. Various in-vitro studies have been conducted to improve the withanolide content in this important plant. Further, emerging metabolomic area like phytochemical genomics has also been applied in case of Withania somnifera for metabolite detection and its structural validation.

Tropinone reductases (TRs) are small proteins belonging to the SDR (short chain dehydrogenase/reductase) family of enzymes. TR-I and TR-II catalyze the conversion of tropinone into tropane alcohols (tropine and pseudotropine, respectively). The steps are intermediary enroute to biosynthesis of tropane esters of medicinal importance, hyoscyamine/scopolamine, and calystegins, respectively. Biosynthesis of tropane alkaloids has been proposed to occur in roots. However, in the present report, a tropine forming tropinone reductase (TR-I) cDNA was isolated from the aerial tissue (leaf) of a medicinal plant, Withania coagulans. The ORF was deduced to encode a polypeptide of 29.34 kDa. The complete cDNA (WcTRI) was expressed in E. coli and the recombinant His-tagged protein was purified for functional characterization. The enzyme had a narrow pH range of substantial activity with maxima at 6.6. Relatively superior thermostability of the enzyme (30% retention of activity at 60 °C) was catalytic novelty in consonance with the desert area restricted habitat of the plant. The in vitro reaction kinetics predominantly favoured the forward reaction. The enzyme had wide substrate specificity but did not cover the substrates of other well-known plant SDR related to menthol metabolism. To our knowledge, this pertains to be the first report on any gene and enzyme of secondary metabolism from the commercially and medicinally important vegetable rennet species.

Tryptophan decarboxylase (EC 4.1.1.28) catalyzes pyridoxal 5'-phosphate (PLP)-dependent decarboxylation of tryptophan to produce tryptamine for recruitment in a myriad of biosynthetic pathways of metabolites possessing indolyl moiety. A recent report of certain indolyl metabolites in Withania species calls for a possible predominant functional role of tryptophan decarboxylase (TDC) in the genome of Withania species to facilitate production of the indolyl progenitor molecule, tryptamine. Therefore, with this metabolic prospection, we have identified and cloned a full-length cDNA sequence of TDC from aerial tissues of Withania coagulans. The functional WcTDC gene comprises of 1506 bp open reading frame (ORF) encoding a 502 amino acid protein with calculated molecular mass and pI value of 56.38 kDa and 8.35, respectively. The gene was expressed in Escherichia coli, and the recombinant enzyme was affinity-purified to homogeneity to discern its kinetics of catalysis. The enzyme (WcTDC) exhibited much higher Km value for tryptophan than for pyridoxal 5'-phosphate and was dedicated to catalyze decarboxylation of only tryptophan or, to a limited extent, of its analogue (like 5-hydroxy tryptophan). The observed optimal catalytic functionality of the enzyme on the slightly basic side of the pH scale and at slightly higher temperatures reflected adaptability of the plant to hot and arid regions, the predominant natural habitat of the herb. This pertains to be the first report on cloning and characterization of heterologously expressed recombinant enzyme from W. coagulans and forms a starting point to further understanding of withanamide biosynthesis.

Omics-Based Approaches for Rice Improvement Somnath Roy, Amrita Banerjee, Somnath Bhattacharya, Arunava Pattanayak, and Kailash C Bansal Practical Omics Approaches for Drought Tolerance in Rice Prashant Vikram, B P Mallikarjuna Swamy, and Arvind Kumar Omics Approaches in Maize Improvement Pawan K Agrawal, Navinder Saini, B Kalyana Babu, and Jagdish C Bhatt Omics Approaches in Pulses Abhishek Bohra, Uday Chand Jha, Balwant Singh, Khela Ram Soren, Indra Prakash Singh, Sushil Kumar Chaturvedi, Nagaswamy Nadarajan, and Debmalya Barh Genetic Engineering in Potato Improvement Elena Rakosy-Tican Omics Applications in Brassica Species Xiaonan Li, Nirala Ramchiary, Vignesh Dhandapani, Su Ryun Choi, and Yong Pyo Lim Integrating Omics Approaches in Sugarcane Improvement Rachayya M Devarumath, Sachin B Kalwade, Pranali A Kulkarni,Suman S Sheelavanthmath, and Penna Suprasanna Recent Advances in Temperate Fruit Crops: An Omics Perspective Md Abdur Rahim and Livio Trainotti Omics Approaches in Tropical Fruit Crops Kundapura V Ravishankar, Kanupriya, Ajitha-kumar Rekha, Anuradha Upadhyay,Chinmaiyan Vasugi, N Vijayakumari, Pooja Kishnani, and Makki R Dinesh Catharanthus roseus: The Metabolome That Represents a Unique Reservoir of Medicinally Important Alkaloids under Precise Genomic Regulation Ashutosh K Shukla and Suman PS Khanuja Omics of Secondary Metabolic Pathways in Withania somnifera Dunal (ashwagandha) Neelam S Sangwan, Laxmi N Misra, Sandhya Tripathi, and Amit K Kushwaha Genetic Engineering in Ornamental Plants Rajesh Kumar Dubey, Simrat Singh, Gurupkar Singh Sidhu, and Manisha Dubey Omics Advances in Tea (Camellia sinensis) Mainaak Mukhopadhyay, Bipasa Sarkar, and Tapan Kumar Mondal Omics Approaches to Improving Fiber Qualities in Cotton Tianzhen Zhang, Xiangdong Chen, and Wangzhen Guo Forestry and Engineered Forest Trees Mohammed Ellatifi Application of Omics Technologies in Forage Crop Improvement Suresh Kumar and Vishnu Bhat Bioenergy Crops Enter the Omics Era Atul Grover, Patade Vikas Yadav, Maya Kumari, Sanjay Mohan Gupta,Mohommad Arif, and Zakwan Ahmed Molecular Farming in the Decades of Omics Dinesh K Yadav, Neelam Yadav, and SM Paul Khurana Natural Pesticidome Replacing Conventional Pesticides Daiane Hansen Intellectual Property Rights in Plant Biotechnology: Relevance, Present Status, and Future Prospects Dinesh Yadav, Gautam Anand, Sangeeta Yadav, Amit K Dubey, Naveen C Bisht,and Bijaya K Sarangi Index

Centella asiatica (L.) Urban is an important medicinal plant and has been used since ancient times in traditional systems of medicine. C. asiatica mainly contains ursane skeleton based triterpenoid sapogenins and saponins predominantly in its leaves. This investigation employed Illumina next generation sequencing (NGS) strategy on a pool of three cDNAs from expanding leaf of C. asiatica and developed an assembled transcriptome sequence resource of the plant. The short transcript reads (STRs) generated and assembled into contigs and singletons, representing majority of the genes expressed in C. asiatica, were termed as 'tentative unique transcripts' (TUTs). The TUT dataset was analyzed with the objectives of (i) development of a transcriptome assembly of C. asiatica, and (ii) classification/characterization of the genes into categories like structural, functional, regulatory etc. based on their function. Overall, 68.49% of the 46,171,131 reads generated in the NGS process could be assembled into a total of 79,041 contigs. Gene ontology and functional annotation of sequences resulted into the identification of genes related to different sets of cellular functions including identification of genes related to primary and secondary metabolism. The wet lab validation of seventeen assembled gene sequences identified to be involved in secondary metabolic pathways and control of reactive oxygen species (ROS) was established by semi-quantitative and real time PCR (qRT-PCR). The validation also included sequencing/size matching of a set of semi-quantitative PCR amplicons with their in silico assembled contig/gene. This confirmed the appropriateness of assembling the reads and contigs. Thus, the present study constitutes the largest report to date on C. asiatica transcriptome based gene resource that may contribute substantially to the understanding of the basal biological functions and biochemical pathways of secondary metabolites as well as the transcriptional regulatory elements and genetic markers. This work sets the stage for multi-faceted future improvement of the plant, through discovery of new genes, marker-assisted breeding or genetic engineering, on this species as well as for other species of Apiaceae and triterpene producing medicinal plants.

Phenological activities of eight woody species planted in Kirtipur (central Nepal) were examined, each for one dry season between September 2001 and June 2003. From Pressure Volume (P-V) analysis, we determined relative water content at zero turgor (RWC z ), osmotic potential at zero turgor (Ψ sz ) and full turgor (Ψ sf ), and bulk modulus of elasticity (e) once a month through the course of dry season. Both evergreen species ( Cotoneaster bacillaris Wall., Quercus lanata Sm., Ligustrum confusum Decne., Woodfordia fruticosa (L.) Kurz.) and deciduous species ( Celtis australis Linn., Alnus nepalensis D.Don., Bauhinia variegata Linn. and Lagerstroemia indica Linn.) put out their new leaves during the dry summer when day length and temperature were increasing. Generally, bud break coincided with concentrated leaf fall during the dry summer and the leaf fall reduced total leaf area to its lowest value. The deciduous species were leafless for one to three months, followed by a prolonged period of leaf production and shoot elongation. Evergreen and deciduous species manifested distinct adaptive strategies to water deficit. Evergreens can reduce osmotic potential (Ψ s ) to its low value and maintain proper water potential (Ψ) gradient from soil to plant, which facilitates absorption of water during dry season. Elastic tissue in deciduous species is coupled with leaf shedding during the dry season; both factors may help maintain proper Ψ s for new growth during dry period. One evergreen species ( Woodfordia fruticosa ) and three deciduous species ( Celtis australis , Bauhinia variegata and Lagerstroemia indica ) have inherently high dehydration tolerance due to their elastic tissue. During drought there has been osmotic adjustment in Quercus lanata , and elastic adjustment in Ligustrum confusum , Celtis australis and Lagerstroemia indica . Key words: Himalayas, Pressure Volume (P-V) curve, relative water content (RWC), osmotic adjustment, elastic adjustment Himalayan Journal of Sciences Vol.4(6) 2007 p.49-56