High temperature and salt stress response in French bean (Phaseolus vulgaris)

Abiotic stresses, such as high temp., and salt stress are major factors which reduce crop productivity. Effects of high temp. (46-​48° C) and salt stress (0.4 M) on French bean (Phaseolus vulgaris)​, a major vegetable crop, were evaluated in terms of antioxidants and antioxidant enzymes in S-​9 cultivar. Both stresses caused similar responses in the plant. Oxidative stress indicators such as H2O2, TBARS, glutathione, ascorbic acid, and proline were significantly elevated. Similarly, antioxidant enzyme, guaiacol-​specific peroxidase (POX) was significantly elevated. Other enzymes, β-​amylase and acid phosphatase (AP) activities were marginally enhanced. However, stresses had contrasting effects on glutathione reductase (GR) and catalase (CAT)​, which were drastically reduced in temp. stress, and elevated in salt stress. No variations were obsd. in AP, POX, and CAT isoenzymes. Patterns of GR and β-​amylase isoenzymes differed between temp. and salt stress. SDS-​PAGE indicated entirely different sets of proteins in temp. and salt stressed seedlings. Growth rate and fresh mass were affected to same extent, relative to their resp. controls. DNA damage was more pronounced under temp. stress than under salt stress. Response mechanism of French bean appears to involve some players which are common to both the stresses, and few specific to individual stress

PERFORMANCE EVALUATION OF GREEN INHIBITORS IN CHLORIDE INDUCED CORROSION OF REINFORCING STEEL EMBEDDED IN CONCRETE

Abstract This study investigates the corrosion inhibition efficiency of some organic inhibitors and compares its performance against inorganic inhibitors. The inorganic inhibitors used in the study were sodium molybdate dihydrate (Na2MoO4·2H2O), benzotriazole, while organic inhibitors were prepared from Azadirachta indica (AI) and Calotropis gigantea (CG) plant. The concrete specimens were contaminated during concrete preparation with 2% NaCl by weight of cement. To evaluate the effect of these inhibitors on corrosion of reinforcing steel, cylindrical concrete specimens with centrally embedded reinforcement were prepared. Further to accelerate the corrosion process the specimens after curing period were exposed to NaCl(4%) solution. Concrete cube specimens were used to evaluate the effect of inhibitors on the compressive strength of concrete. The results of the study indicated that the corrosion inhibitors investigated in this study did not have adverse effects on compressive strength of concrete. Furthermore, Benzotriazole proved to be effective in delaying corrosion initiation of reinforcing steel embedded in concrete specimens contaminated with NaCl compared to Na2MoO4·2H2O. Observing the performance of both organic inhibitors, AI inhibitor performed better in mitigating the reinforcing steel corrosion compared to CG

Identification of miRNAs from French bean (Phaseolus vulgaris) under low nitrate stress

Objective: In this study, we report the role of miRNAs involved under nitrogen starvation from widely grown vegetable crop, French bean. In recent years, a great deal of attention has been paid to the elucidation of miRNAs involved in low nitrate stress. Methods: To identify miRNAs expressed under stress, cDNA libraries were analyzed. Results: We reported the nine potential miRNAs with 67 targets involved in nutrient transporters and other stress specific genes. Among the miRNA sequences obtained 6 sequences belong to miR172 family, one with miR169. RT-PCR analysis of expression of miR172 family was induced upon low nitrate stress while miR169 family was repressed. In addition, Pvu-SN7b and Pvu-miR16 may be new members of miRNA172 and miR169 families, respectively. Conclusion: The targets of Pvu-SN7b were major protein kinases, one among which is the Protein Kinase CK2. CK2 Kinase is found to involve in transcription-directed signaling, gene control and cell-cycle regulation. Other targets of Pvu-SN7b were involved in DNA-dependent transcription regulation, photo-periodism, calcium-mediated signaling. Pvu-miR16 targets Thymidine kinase, the key enzyme of deoxy-nucleotide synthesis. The cleavage of these targets affects cell proliferation there by affecting nodule formation. Pvu-miR8 inhibits translation of its target protein Pre-protein translocase, a membrane-bound protein transporter involved in trans-membrane protein transportation. Together these results denote the response and role of miRNAs to nitrate-limiting conditions in French bean

Identification of microRNAs and their targets in Finger millet by high throughput sequencing

MicroRNAs are short non-coding RNAs which play an important role in regulating gene expression by mRNA cleavage or by translational repression. The majority of identified miRNAs were evolutionarily conserved; however, others expressed in a species-specific manner. Finger millet is an important cereal crop; nonetheless, no practical information is available on microRNAs to date. In this study, we have identified 95 conserved microRNAs belonging to 39 families and 3 novel microRNAs by high throughput sequencing. For the identified conserved and novel miRNAs a total of 507 targets were predicted. 11 miRNAs were validated and tissue specificity was determined by stem loop RT-qPCR, Northern blot. GO analyses revealed targets of miRNA were involved in wide range of regulatory functions. This study implies large number of known and novel miRNAs found in Finger millet which may play important role in growth and development. © 2015 Elsevier B.V

Genome wide analysis of NAC transcription factors and their expression pattern during high temperature and drought stress in groundnut

NAC (NAM, ATAF1/2 and CUC2) is a prime plant specific transcription factor, which plays a pivotal role in stress signaling. Excavating a relatively large number of NAC TFs under complex environmental cues and understanding their molecular basis,\ua0remains a challenge. The objective of this study was to analyse a total of 76 NAC transcription factors of which 38 were from Arachis duranensis (AdNAC) and Arachis ipaensis (AiNAC) for phylogeny, chromosomal location, conserved motif identification including membrane bound NTLs (NAC trans-membrane like), promoter analysis and expression profiles under high temperature and drought stress.\ua0The study led to the identification of eight membrane bound NTLs, such as AdNAC26, AdNAC36, AiNAC16, AiNAC17, AiNAC37, AdNAC14, AiNAC12, and AiNAC29, and revealed that majority of NAC proteins had four NAC domain- containing conserved motifs and were localised at the nucleus. The study also reveals AdNAC21 and AiNAC3 as positive regulators under both stress conditions. Our results provide a basis for selection of promising stress- responsive NAC candidates for further functional analysis, leading to development of transgenics with improved productivity of groundnut varieties under drought and high temperature.NAC (NAM, ATAF1/2 et CUC2) est un facteur sp\ue9cifique primordial dans la transcription chez la plante, qui joue un r\uf4le principal dans la signalisation des stresses. Fouiller un nombre relativement important de NAC TFs sous le complexe des signaux environnementaux et comprendre leur base mol\ue9culaire, demeurent un d\ue9fi. L\u2019objectif de cette \ue9tude \ue9tait d\u2019analyser un total de 76 facteurs de transcription desquels 38 sont de Arachis duranensis (AdNAC) et Arachis ipaensis (AiNAC) pour la phylog\ue9nie, la localisation chromosomique, l\u2019identification du motif conserv\ue9 y comprises la membrane li\ue9e NTLs (semblable \ue0 NAC transe-membrane), analyse du promoteur et les profils d\u2019expression sous le stress de haute temp\ue9rature et de s\ue9cheresse. L\u2019\ue9tude a conduit \ue0 l\u2019identification de huit membranes NTLs li\ue9es, telles que AdNAC26, AdNAC36, AiNAC16, AiNAC17, AiNAC37, AdNAC14, AiNAC12, et AiNAC29, et a r\ue9v\ue9l\ue9 que la majorit\ue9 des prot\ue9ines NAC ont quatre domaines NAC- contenant des motifs conserv\ue9s et sont localis\ue9s dans le noyau. L\u2019\ue9tude a aussi r\ue9v\ue9l\ue9 AdNAC21 et AiNAC3 comme r\ue9gulateurs positifs sous les deux conditions \ue0 la fois. Nos r\ue9sultats ont fourni une base pour la s\ue9lection des NAC candidats donnant de r\ue9ponses satisfaisantes aux stresses pour une analyse fonctionnelle avanc\ue9e, conduisant au d\ue9veloppement des transg\ue9niques avec des vari\ue9t\ue9s d\u2019arachide \ue0 rendement am\ue9lior\ue9 sous la s\ue9cheresse et une haute temp\ue9rature

Imatinib resistance mutation analysis: experience from a tertiary oncology center

Purpose: BCR-ABL kinase domain (KD) mutations account for 50-90% of the imatinib resistance observed in patients of CML-chronic phase. In CML-CP patients receiving imatinib first-line, mutation analysis is recommended in case of failure or suboptimal response using European LeukemiaNet (ELN) criteria. The present study was carried out at a tertiary oncology centre in south India to assess which mutations accounted for resistance to imatinib among patients of chronic phase CML being treated with imatinib.Methods: This was a retrospective observational study. We analyzed patients who were tested for imatinib resistance mutation in view of suboptimal responses while on imatinib or imatinib failure. Direct sequencing of the BCR-ABL transcript by the Sanger method was used for IRMA testing.Results: Out of 120 tested for IRMA, 36 (30%) had detectable mutations. We observed a higher frequency of mutations at amino acids T315, F359 and M351T.Conclusions: Among the patients who were tested for imatinib resistance mutation in view of suboptimal responses while on imatinib or imatinib failure, 30% had IRMA +ve mutations. The high incidence of imatinib resistance in present study may be attributed to the fact that our patients were given higher dose of imatinib (600 mg), if they failed to achieve CCyR at 12 months or CHR at 3 months as they could not afford second generation TKIs

Imatinib resistance mutation analysis: experience from a tertiary oncology center

Purpose: BCR-ABL kinase domain (KD) mutations account for 50-90% of the imatinib resistance observed in patients of CML-chronic phase. In CML-CP patients receiving imatinib first-line, mutation analysis is recommended in case of failure or suboptimal response using European LeukemiaNet (ELN) criteria. The present study was carried out at a tertiary oncology centre in south India to assess which mutations accounted for resistance to imatinib among patients of chronic phase CML being treated with imatinib.Methods: This was a retrospective observational study. We analyzed patients who were tested for imatinib resistance mutation in view of suboptimal responses while on imatinib or imatinib failure. Direct sequencing of the BCR-ABL transcript by the Sanger method was used for IRMA testing.Results: Out of 120 tested for IRMA, 36 (30%) had detectable mutations. We observed a higher frequency of mutations at amino acids T315, F359 and M351T.Conclusions: Among the patients who were tested for imatinib resistance mutation in view of suboptimal responses while on imatinib or imatinib failure, 30% had IRMA +ve mutations. The high incidence of imatinib resistance in present study may be attributed to the fact that our patients were given higher dose of imatinib (600 mg), if they failed to achieve CCyR at 12 months or CHR at 3 months as they could not afford second generation TKIs.</p

Interplay of nuclear receptors (ER, PR, and GR) and their steroid hormones in MCF-7 cells

Steroid hormones and their nuclear receptors play a major role in the development and progression of breast cancer. MCF-7 cells are triple-positive breast cancer cells expressing estrogen receptor (ER), progesterone receptor (PR), and glucocorticoid receptor (GR). However, interaction and their role in expression pattern of activator protein (AP-1) transcription factors (TFs) are not completely understood. Hence, in our study, MCF-7 cells were used as an in vitro model system to study the interplay between the receptors and hormones. MCF-7 cells were treated with estradiol-17β (E2), progesterone (P4), and dexamethasone (Dex), alone or in combination, to study the proliferation of cells and expression of AP-1 genes. MTT assay results show that E2 or P4 induced the cell proliferation by more than 35 %, and Dex decreased the proliferation by 26 %. E2 and P4 are found to increase ERα by more than twofold and c-Jun, c-Fos, and Fra-1 AP-1 TFs by more than 1.7-fold, while Dex shows opposite effect of E2- or P4-induced effect as well as effect on the expression of nuclear receptors and AP-1 factors. E2 antagonist Fulvestrant (ICI 182,780) found to reduce proliferation and E2-induced expression of AP1-TFs, while P4 or Dex antagonist Mifepristone (RU486) is found to block GR-mediated expression of NRs and AP-1 mRNAs. Results suggest that E2 and P4 act synergistically, and Dex acts as an antagonist of E2 and P4

Aqueous areca nut extract induces oxidative stress in human lung epithelial A549 cells: Probable role of p21 in inducing cell death

Areca nut a well-known masticator used across globe. Habitual chewing of areca nut is associated with serious oral health effects. However, the role of areca nut in oxidative stress induction and cell death is less understood. Hence, in the present study we aimed to evaluate the toxic mechanism of areca nut extract on human lung epithelial A549 cells. Cells were treated with or without aqueous areca nut extract and cell viability was measured by MTT assay. Cells treated with areca nut extract show reduced viability in a dose dependent manner with the IC50 of 0.5 concentration. Areca nut extract induced the reactive oxygen species (ROS), lipid peroxidation followed by membrane damage with leakage of lactate dehydrogenase (LDH) enzyme. Cells with continuous exposure of areca nut extract depletes the free radical neutralizing anti-oxidant enzymes like superoxide dismutase (SOD), Glutathione peroxidase (GSH-Px) and Glutathione-S-transferase (GST). Further, the analysis of mRNA expression of apoptotic genes and cell cycle regulators show decreased expression of anti-apoptotic gene (Bcl-2), Cyclin E1, Cyclin D1, CDK4, Rb and p53 whereas induced expression of p21 and marginal increase of pro-apoptotic gene (Bax) confirms the toxic nature of areca nut. Thus, cell death due to areca nut exposure may be through different mechanism rather than the conventional apoptotic pathway, where p21 induction might be independent of p53 action, which possibly suggests that there may be a role of p21 in oxidative stress induced cell death. Further FACS analysis confirms cell death in areca nut treated cells. © 2016 Elsevier Inc