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11.
Kamala Gupta Bhaskar Gupta Bharati Ghosh Dibyendu Narayan Sengupta 《Acta Physiologiae Plantarum》2012,34(1):29-40
Importance of higher polyamines, spermidine, and spermine, in relation to the mechanism and adaptation to combat abiotic stress
has been well established in cereals. Owing to their polycationic nature at physiological pH, polyamines bind strongly to
negative charges in cellular components such as nucleic acids, various proteins, and phospholipids. To study the physiological
role of polyamine during salinity stress, phosphorylation study was carried out in cytosolic soluble protein fraction isolated
from the roots of salt tolerant (Nonabokra) and salt sensitive (M-1-48) rice cultivars treated with none (control), NaCl (150 mM,
16 h), spermidine (1 mM, 16 h) or with abscisic acid (100 μM, 16 h). A calcium independent auto regulatory 42 kDa protein
kinase was found to phosphorylate myelin basic protein and casein but not histone. Interestingly, this was the only protein
to be phosphorylated in root cytosolic fraction during NaCl/abscisic acid/spermidine treatment indicating its importance in
salinity mediated signal transduction. This is the first report of polyamine as well as abscisic acid induced protein kinase
activity in rice root in response to salinity stress. 相似文献
12.
A deltamethrin containing insecticide formulation (Decis®) was evaluated for its toxic potential in developing chick embryos. For the present study, three water emulsified concentrations of Decis® (12.5 mg L?1, 25 mg L?1, and 50 mg L?1) were used. Fertilized eggs of Gallus domesticus were immersed in these three concentrations of the insecticide for 60 min at 37°C on day 0 of incubation and kept for incubation till embryonic day 7. Recovered embryos were evaluated for teratogenic and biochemical changes. The results revealed that administration of Decis® at its lower concentrations (12.5 mg L?1 and 25 mg L?1) did not show any significant teratological changes but the significant number of abnormal survivors was observed at 50 mg L?1 of dose concentration when compared with vehicle-treated control. Among biochemical changes, total glycogen and RNA contents of embryos was significantly decreased at 25 mg L?1 and 50 mg L?1 of Decis® concentrations. Similarly, significant alteration (p ≤ .05) was observed in alanine transaminase activity at 50 mg L?1 concentration of Decis®. Thus, the present study concluded that the no-effect-level for developmental toxicity for Decis® is below the concentration of 25 mg L?1 under standard laboratory conditions. 相似文献
13.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
14.
Bhaskar Kahali Jee‐Eun Kim Umesh Karandikar Clifton P. Bishop Ashok P. Bidwai 《Genesis (New York, N.Y. : 2000)》2010,48(1):44-55
Analysis of the retinal defects of a CK2 phosphomimetic variant of E(spl)M8 (M8S159D) and the truncated protein M8* encoded by the E(spl)D allele, suggest that the nonphosphorylated CtD “autoinhibits” repression. We have investigated this model by testing for inhibition (in “trans”) by the CtD fragment in its nonphosphorylated (M8‐CtD) and phosphomimetic (M8SD‐CtD) states. In N+ flies, ectopic M8‐CtD compromises lateral inhibition, i.e., elicits supernumerary bristles as with loss of N signaling. This antimorphic activity of M8‐CtD strongly rescues the reduced eye and/or bristle loss phenotypes that are elicited by ectopic M8SD or wild type M8. Additionally, the severely reduced eye of Nspl/Y; E(spl)D/+ flies is also rescued by M8‐CtD. Rescue is specific to the time and place, the morphogenetic furrow, where “founding” R8 photoreceptors are specified. In contrast, the phosphomimetic M8SD‐CtD that is predicted to be deficient for autoinhibition, exhibits significantly attenuated or negligible activity. These studies provide evidence that autoinhibition by the CtD regulates M8 activity in a phosphorylation‐dependent manner. genesis 48:44–55, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
15.
C. Bhaskar Palakolanu S. Reddy K. Sarath Chandra Sudeep Sabde Debashis Mitra Anand K. Kondapi 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(4):780-790
Early pregnancy associated protein-1 (Epap-1), a 90 kDa glycoprotein present in first trimester placental tissue, inhibits HIV-1 entry through interaction with HIV-1 gp120 at V3 and C5 regions. In the present study, we have identified the specific 32 mer region of Epap-1 that can interact with V3 loop. This was achieved by docking between Epap-1 molecular model and gp120 and studying the interaction of peptides with gp120 in vitro. Out of four peptides analyzed, two peptides (P-2 and P-3) showed significant interaction with V3 domain (N = 8; N = 7) of gp120. In the studies conducted using soluble gp120 and virus, peptide P-2 has shown conserved interaction at V3 loop regions recognized by 257D and F425 antibodies and higher anti-viral activity. Also, P-2 inhibited cell fusion mediated dye transfer between gp120 expressing HL2/3 and CD4 expressing Sup T1 cells suggesting its inhibition of viral entry, which is further confirmed by its action on HIV infection mediated by Tat activated beta gal expression in TZM-bl cells. Further optimization of P-2 peptide showed that the anti-viral activity and gp120 interaction residues lie in the N-terminal region of the peptide. These results together suggest that P-2 inhibits viral entry through specific interaction at V3 loop region. 相似文献
16.
Bhaskar Ponugoti Fanxing Xu Chenying Zhang Chen Tian Sandra Pacios Dana T. Graves 《The Journal of cell biology》2013,203(2):327-343
Keratinocyte mobilization is a critical aspect of wound re-epithelialization, but the mechanisms that control its precise regulation remain poorly understood. We set out to test the hypothesis that forkhead box O1 (FOXO1) has a negative effect on healing because of its capacity to inhibit proliferation and promote apoptosis. Contrary to expectations, FOXO1 is required for keratinocyte transition to a wound-healing phenotype that involves increased migration and up-regulation of transforming growth factor β1 (TGF-β1) and its downstream targets, integrin-α3 and -β6 and MMP-3 and -9. Furthermore, we show that FOXO1 functions in keratinocytes to reduce oxidative stress, which is necessary to maintain cell migration and prevent cell death in a TGF-β1–independent manner. Thus, our studies identify a novel function for FOXO1 in coordinating the response of keratinocytes to wounding through up-regulation of TGF-β1 and other factors needed for keratinocyte migration and protection against oxidative stress, which together promote migration and decrease apoptosis. 相似文献
17.
Santosh S. Chobe Bhaskar S. Dawane Khaled M. Tumbi Prajwal P. Nandekar Abhay T. Sangamwar 《Bioorganic & medicinal chemistry letters》2012,22(24):7566-7572
The DNA molecule is a target for plethora of anticancer and antiviral drugs that forms covalent and non-covalent adducts with major or minor groove of DNA. In present study we synthesized series of novel Pyrazolo [1,5-a]pyrimidine derivatives. The newly synthesized compounds were characterized by elemental analysis, IR, 1H NMR, and mass spectral data. The selected compounds were studied for interaction with Calf thymus DNA (CT-DNA) using electronic spectra, viscosity measurement and thermal denaturation studies. Further, molecular interactions were revealed for compound IIIa and IVa by computational methodologies. The preferred mode of ligand binding with double helical DNA as well as preferable DNA groove were explored by molecular docking in different DNA models. 相似文献
18.
Modulation of ROS/MAPK signaling pathways by okadaic acid leads to cell death via,mitochondrial mediated caspase-dependent mechanism 总被引:1,自引:0,他引:1
Ravindran J Gupta N Agrawal M Bala Bhaskar AS Lakshmana Rao PV 《Apoptosis : an international journal on programmed cell death》2011,16(2):145-161
Okadaic acid (OA) is a specific and potent protein phosphatase inhibitor and tumor promoter. The present study establishes the role of reactive oxygen species (ROS) and mitogen activated protein kinases in cell death induced by okadaic acid. The study showed that okadaic acid is cytotoxic at 10 nM with an IC50 of 100 nM in U-937 cells. The CVDE assay and mitochondrial dehydrogenase assay showed a time dependent cytotoxicity. The phase contrast visualization of the OA treated cells showed the apoptotic morphology and was confirmed with esterase staining for plasma membrane integrity. OA activated caspases-7, 9 and 3, PARP cleavage and induced nuclear damage in a time and dose dependent manner. Compromised mitochondrial membrane potential, release of cytochrome-c and apoptosis inducing factor confirms the involvement of mitochondria. A time dependent decrease in glutathione levels and a dose dependent increase in ROS with maximum at 30 min were observed. ROS scavenger-N-acetyl cysteine, mitochondrial stabilizer-cyclosporin-A, and broad spectrum caspase inhibitor Z-VAD-FMK inhibited the OA induced caspase-3 activation, DNA damage and cell death but caspase-8 inhibitor had no effect. OA activated p38 MAPK and JNK in a time dependent manner, but not ERK½. MAP kinase inhibitors SB203580, SP600125 and PD98059 confirm the role of p38 MAPK and JNK in OA induced caspase-3 activation and cell death. Over all, our results indicate that OA induces cell death by generation of ROS, and activation of p38 MAPK and JNK, and executed through mitochondrial mediated caspase pathway. 相似文献
19.
Influence of recirculation on the performance of anaerobic sequencing batch biofilm reactor (AnSBBR) was studied in the process of treating hypersaline (total dissolved inorganic solids (TDIS) approximately 26 g/l) and low biodegradable (BOD/COD approximately 0.3) composite chemical wastewater. Significant enhancement in the substrate removal efficiency and biogas yield was observed after introducing the recirculation to the system. Maximum efficiency (COD removal efficiency - 51%; SDR - 3.14 kg COD/cum-day) was observed at recirculation to feed (R/F) ratio of 2 (OLR - 6.15 kg C OD/cum-day; HLR - 2.30 cum (liquid)/cum day; UFV(A) - 0.023 m/h). Subsequent increase of R/F to 3 (OLR - 6.15 kg COD/cum-day; HLR - 3.07cum (liquid)/cum-day; UFV(A) - 0.035 m/h) resulted in reduction in COD removal efficiency (32%; SDR - 1.97 kg COD/cum-day). The enhanced performance of the system due to the introduction of recirculation was attributed to the improvement in the mass transfer between the substrate present in the bulk liquid and the attached biofilm. The hydrodynamic behavior due to recirculation mode of operation reduced the concentration gradient (substrate inhibition) of substrate and reaction by-products (VFA) resulting in mixed flow conditions. 相似文献
20.
Vinod Kumar Ashwani Sharma Bellur Chayapathy Narasimha Prasad Harishchandra Bhaskar Gururaj Parvatam Giridhar Gokare Aswathanarayana Ravishankar 《Acta Physiologiae Plantarum》2007,29(1):11-18
Direct shoot bud induction and plant regeneration was achieved in Capsicum frutescens var. KTOC. Aseptically grown seedling explants devoid of roots, apical meristem and cotyledons were inoculated in an inverted
position in medium comprising of Murashige and Skoog (Physiol Plant 15:472–497, 1962) basal medium supplemented with 2-(N-morpholine) ethanesulphonic acid buffer along with 2.28 μM indole-3-acetic acid, 10 μM silver nitrate and either of 13.31–89.77 μM
benzyl adenine (BA), 9.29–23.23 μM kinetin, 0.91–9.12 μM zeatin, 2.46–9.84 μM 2-isopentenyl adenine. Profuse shoot bud induction
was observed only in explants grown on a media supplemented with BA (26.63 μM) as a cytokinin source and 19.4 ± 4.2 shoot
buds per explant was obtained in inverted mode under continuous light. Incorporation of polyamine inhibitors in the culture
medium completely inhibited shoothoot bud induction. Incorporation of exogenous polyamines improved the induction of shoot
buds under 24 h photoperiod. These buds were elongated in MS medium containing 2.8 μM gibberellic acid. Transfer of these
shoots to hormone-free MS medium resulted in rooting and rooted plants were transferred to fields. This protocol can be efficiently
used for mass propagation and presumably also for regeneration of genetically transformed C. frutescens. 相似文献