<i>De novo</i> transcriptome profiling unveils the regulation of phenylpropanoid biosynthesis in unripe <i>Piper nigrum</i> berries

BACKGROUND: Black pepper (Piper nigrum L.) is rich in bioactive compounds that make it an imperative constituent in traditional medicines. Although the unripe fruits have long been used in different Ayurvedic formulations, the mechanism of gene regulation resulting in the production of the bioactive compounds in black pepper is not much investigated. Exploring the regulatory factors favouring the production of bioactive compounds ultimately help to accumulate the medicinally important content of black pepper. The factors that enhance the biosynthesis of these compounds could be potential candidates for metabolic engineering strategies to obtain a high level production of significant biomolecules. RESULTS: Being a non-model plant, de novo sequencing technology was used to unravel comprehensive information about the genes and transcription factors that are expressed in mature unripe green berries of P. nigrum from which commercially available black pepper is prepared. In this study, the key gene regulations involved in the synthesis of bioactive principles in black pepper was brought out with a focus on the highly expressed phenylpropanoid pathway genes. Quantitative real-time PCR analysis of critical genes and transcription factors in the different developmental stages from bud to the mature green berries provides important information useful for choosing the developmental stage that would be best for the production of a particular bioactive compound. Comparison with a previous study has also been included to understand the relative position of the results obtained from this study. CONCLUSIONS: The current study uncovered significant information regarding the gene expression and regulation responsible for the bioactivity of black pepper. The key transcription factors and enzymes analyzed in this study are promising targets for achieving a high level production of significant biomolecules through metabolic engineering. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12870-022-03878-1

Micropropagation of Clitoria ternatea L. (Papilionaceae) through callus regeneration and shoot tip multiplication

Methods for rapid multiplication of&nbsp;Clitoria tematea&nbsp;through callus regeneration and shoot tip cultures are described. Stem and leaf explants cultured on Gamborg's basal medium supplemented with 0.01-1 mg 1-1 2, 4-dichlorophenoxy acetic acid in combination with 0.01-2 mgl-1 kinetin or 1-3 mgl-1 benzyl adenine alone formed callus. These calli on transfer to Gamborg's medium supplemented with 1-2 mgl-1 benzyl adenine and 2-3 mgl-1 indole-3-acetic acid or 3-4 mg 1-1 indole-3-acetic acid alone developed shoot buds and the number of regenerated buds was maximum (8-10) with 2 mgl-1 benzyl adenine and indole-3-acetic acid containing medium. Callus retained the same morphogenic potential even after repeated subculturing .. Multiple shoots were induced from the shoot tips cultured on Gamborg's medium containing 3-5 mgl-1 benzyl adenine, 1mgl-1 benzyl adenine with 2 mgl-1 gibberellic acid. Shoots, developed from shoot tips, multiplied further by subculturing in the same medium or from callus, were rooted in Gamborg's medium containing 1-3 mgl-1 I-naphthalene acetic acid. The regenerated plants were transferred initially to vermiculite and later grown to maturity in the green house in garden soil and sand (1:3). &nbsp; &nbsp

Inkjet‐Printed Self‐Hosted TADF Polymer Light‐Emitting Diodes

Thermally activated delayed fluorescent (TADF) materials are extensively investigated as organic light-emitting diodes (OLEDs) with TADF emitting layers demonstrating high efficiency without the use of heavy metal complexes. Therefore, solution-processable and printable TADF emitters are highly desirable, moving away from expensive vacuum deposition techniques. In addition, using emissive materials not requiring an external host simplifies the fabrication process significantly. Herein, OLEDs using a solution-processable TADF polymer that do not need an external host are introduced. The non-conjugated TADF polymer features a TADF emitter (4-(9H-carbazol-9-yl)-2-(3′-hydroxy-[1,1′-biphenyl]-3-yl)-isoindoline-1,3-dione) as a side chain, as well as a hole-transporting side chain and an electron-transporting side chain on an inactive polymer backbone. All organic layers of the OLEDs are fabricated using solution processing methods. The OLEDs with inkjet-printed emissive layers have comparable maximum current and external quantum efficiency as their spin-coated counterparts, exceeding luminance of 2000 cd m$^{-2}$. The herein-explored strategy is a viable route toward self-hosted printable TADF OLEDs

<i>In vitro</i> organogenesis and genetic transformation in popular <i>Cucumis sativus</i> L. <span style="font-size:14.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:Fd1825245-Identity-H;color:black;mso-ansi-language: EN-IN;mso-fareast-language:EN-IN;mso-bidi-language:HI" lang="EN-IN">through <i>Agrobacterium tumefaciens</i></span>

329-333The effect of growth regulators and culture conditions on the morphogenetic response of cotyledonary leaf discs was studied in popular cucumber variety (Cucumis sativus cv. Sheetal). Organogenesis was induced directly without any intervening callus phase on Murashige and Skoog medium supplemented with different concentrations of benzyladenine and indole propionic acid. Best results (93%)were obtained in the presence of the 4mg/L benzyladenine and 1 mg/L IPA. The elongated shoots were rooted in basal medium with 1 mg/L indole butyric acid, hardened and transferred to the field conditions. Genetic transformation system has been established for Cucumis sativus cv. Sheetal, plants by infecting cotyledonary explants with Agrobacterium tumefaciens strain LBA4404 carrying binary plasmid pBIl21 , which contains scorable marker,β-glucuronidase and selectable marker nptll under the CaMV 35S promoter. Infection was most effective when explants were infected with Agrobacterium for 15 min and co-cultivated for 2 days in the co-cultivation medium. Shoots were regenerated directly from cotyledonary leaf explants in the presence of kanamycin (50μg/ml) and analysed. Southern blot analysis confirmed that transformation had occurred. This method will allow genetic improvement of this crop by the introduction of agronomically important genes.</span

In vitro micropropagation of Piper longum - an important medicinal plant

Efficient and rapid tissue culture systems were developed for Piper longum, an important medicinal plant, through shoot tip multiplication and direct regeneration. Multiple shoots were induced from shoot tips cultured on agar-based Murashige and Skoog (MS) medium containing 4.44-22.19 µ M benzyladenine (BA) and 4.64-13.9µ M kinetin (K). Maximum number of shoots were induced with 8.9 µ M BA and 4.64 µ M K. Adventitious shoot regeneration from leaf segments was achieved on MS containing 3.6-22.19 µ M BA along with 3.31-12.4 µ M picloram (P). Shoot differentiation occurred directly from the leaf bases without intermediale callus formation. Maximum shoot buds were obtained on MS medium with 17.76 µ M BA and 8.28 µ M P. Elongated shoots were separated and rooted in MS supplemented with 2.46 µM indole butyric acid (IBA). Plantlets, thus developed were established in soil

A deeper view into the significance of simple sequence repeats in pre-miRNAs provides clues for its possible roles in determining the function of microRNAs

Abstract Background The central tenet of ‘genome content’ has been that the ‘non-coding’ parts are highly enriched with ‘microsatellites’ or ‘Simple Sequence Repeats’ (SSRs). We presume that the presence and change in number of repeat unit (n) of SSRs in different genomic locations may or may not become beneficial, depending on the position of SSRs in a gene. Very few studies have looked into the existence of SSRs in the hair-pin precursors of miRNAs (pre-miRNAs). The interplay between SSRs and miRNAs is not yet clearly understood. Results Considering the potential significance of SSRs in pre-miRNAs, we analysed the miRNA hair-pin precursors of 171 organisms, which revealed a noticeable (29.8%) existence of SSRs in their pre-miRNAs. The maintenance of SSRs in pre-miRNAs even in the complex, highly evolved phyla like Chordata and Magnoliophyta shed light upon its diverse functions. Putative effects of SSRs in either regulating the biogenesis or function of miRNAs were more underlined based on computational and experimental analysis. A preliminary computational analysis to explore the relevance of such SSRs maintained in pre-miRNA sequences led to the detection of splicing regulatory elements (SREs) either in or near to the SSRs. The absence of SSRs correspondingly decreased the detection of SREs. Conclusion The present study is the first implication for the possible involvement of SSRs in shaping the SREs to undergo Alternative Splicing events to produce miRNA isoforms in accordance with different stress environments. This part of work well demonstrates the importance of studying such consistently maintained SSRs residing in pre-miRNAs and can enhance more and more research towards deciphering the exact function of SSRs in the near future

Journal of Proteomics &amp; Bioinformatics- Open Access www.omicsonline.com Research Article JPB/Vol.2/July 2009 Molecular Characterization of Novel form of Type III Polyketide Synthase from Zingiber Officinale Rosc. and its Analysis using Bioinformatics Meth

Copyright: © 2009 Radhakrishnan EK, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Enzymes of Type III polyketide synthase superfamily play an important role in the biosynthesis of medicinal natural products in plants. The PKSs generate the diversity of polyketide derivatives by changing their preference for starter molecules, the number of acetyl additions catalysed and the cyclisation of the polyketide intermediates. The amazing structural features of gingerol and related compounds of ginger (Zingiber officinale Rosc., Zingiberaceae) provide a genomic insight in to the presence of novel forms of PKS. The current study describes the isolation and characterisation of a novel of PKS from Z. officinale using degenerate oligonucleotide based PCR method. The inducible expression of recombinant ZoPKS in E. coli resulted in the formation of a protein with approximate molecular weight of 43kD. The comparative sequence and phylogenetic analysis of ZoPKS shows its significant variation from already identified PKSs. The novelty of the ZoPKS was further confirmed by homology modeling based comparative structural bioinformatics analysis. The novel form of PKS identified i

Isolation of morphovariants through plant regeneration in <i>Agrobacterium rhizogenes</i> induced hairy root cultures of <i>Plumbago rosea</i> L.

435-441 In vitro raised shoots of Plumbago rosea L. were infected with A4 strain of Agrobacterium rhizogenes to initiate hairy root formation, which produced 3.0±0.33 hairy roots per incision on explants in 20 d incubation. Southern blot analysis confirmed the integration of T-DNA into the genome of the roots. The hairy roots were cultured on MS agar medium supplemented with 2.0 mg/L BAP to induce the formation of shoots (3.2±0.24) of 0.2-0.4 cm length in 7-8 wks. Isolated shoots were multiplied through sub culturing in the presence of 0.5 mg/L BAP and the resultant shoots were subjected to combined elongation (3.29±0.16 cm) and rooting (12.6±0.57) in a medium supplemented with 0.1 mg/L IBA. The rooted plants were invariably abnormal with short internodes and wrinkled leaves showing 34.5% establishment in 2 months after transplantation in polybags and rearing under 75% sunlight in a shade house. Out of 38 plants transferred to the field, 20 (52.6%) survived and grew over 10-month period to reveal variations in morphological and growth characters. The growth of all the hairy root-derived plants was slow to varied extent, 13 among them retaining actively growing hairy roots and shoots having short internodes and expanded leaves, one with emerging normal shoot and a tuberous root in the midst of the abnormal shoot and hairy roots and the rest with hairy roots as well as 1-2 normal roots and abnormal shoots having wrinkled leaves. The biomass production ability of the transformed plants contributed by foliage and root characters was poor compared to plants raised from the nodal explants of normal shoot cultures. Southern blot analysis of DNA further confirmed the presence of bacterial T-DNA in these established plants in the field after 10 months. The demonstrated hairy root regeneration system including field establishment of the plants may be useful for scoring new variations especially in non-seed setting P. rosea.</smarttagtype

Imprints of PGPB association on the metabolic dynamism of <i>Piper nigrum</i>

Endophytes are endosymbiotic microorganisms that coexist within different plant species which assist the host in multifarious ways without causing any detrimental effects on the plant well-being. The current study is focused on the bacterial isolates found in the Piper nigrum in vitro culture in the basal MS medium. The growth of these bacterial isolates even after repeated surface sterilization of the explant concludes the nature of these isolates as endophytes and these isolates were identified as Pantoea sp., Luteibacter sp., Herbaspirillum sp., and Agrobacterium sp. through 16srRNA. The endophytes were tested for their potential to aid plant development by assessing the production of Indoleacetic Acid, Ammonia, Hydrogen Cyanide, 1-aminocyclopropane-1-carboxylic acid deaminase, Siderophore, fixation of Nitrogen, solubilization of Phosphate, heavy metal and salt tolerance. Pantoea sp. and Herbaspirillum sp. were found tolerant against salt and heavy metal stress respectively. Based on plant growth promotion assays, Pantoea sp. and Agrobacterium sp. were further selected for metabolomic profiling. The results indicated the effects of isolates on primary and secondary metabolite biogenesis, aminoacyl-tRNA synthesis and amino acid metabolic pathways. The profiling of important metabolites linked to crop development, revealing its metabolic mechanism of plant growth promoting activities facilitated through selected Plant Growth Promoting Bacteria.</p