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41.
Arup Ghosh Jitendra Chikara D. R. Chaudhary Aruna R. Prakash G. Boricha A. Zala 《Journal of Plant Growth Regulation》2010,29(3):307-315
Although the process for making EN 14214 grade Jatropha methyl ester (biodiesel) capable of running unmodified diesel engines in neat form has been demonstrated, getting higher
seed yield from Jatropha shrubs in wastelands is critical to the success of Jatropha biodiesel. But, low productivity is inherent to many Jatropha curcas germplasms and raising large-scale plantations using such untested planting material can lead to wasteful expenditures. Unreliable
and poor flowering and fruiting are important factors responsible for low productivity in the species. Although much is known
about growth retardants applied to field and horticultural crops, their role in improving the seed productivity of Jatropha has never been explored. Here we report for the first time that paclobutrazol could be an extremely useful chemical, whose
dose and time of application, if optimized, can significantly reduce unwanted vegetative growth, with concomitant improvement
in yield and seed oil content of Jatropha. In the year following application of paclobutrazol, an unexpected increase in seed yield, as high as 1127% relative to controls,
was obtained from one such unproductive Jatropha germplasm. We hypothesize that low seed production in this species may be a result of excess vegetative growth caused by
an unfavorable endogenous hormonal configuration which competes with growth and development of flower, fruit, or seed. This
undesired physiological state can be reversed by paclobutrazol application to achieve maximum oil yield from this energy shrub
that holds great promise in the future. 相似文献
42.
Jantana Keereetaweep Aruna Kilaru Ivo Feussner Kent D. Chapman 《FEBS letters》2010,584(14):3215-15214
The lipoxygenase (LOX) pathway was proposed to compete with hydrolysis and be partly responsible for the metabolism of polyunsaturated N-acylethanolamines (PU-NAEs). Treatment of Arabidopsis seedlings with lauroylethanolamide (NAE 12:0) resulted in elevated levels of PU-NAE species, and this was most pronounced in plants with reduced NAE hydrolase activity. Enzyme activity assays revealed that NAE 12:0 inhibited LOX-mediated oxidation of PU lipid substrates in a dose-dependent and competitive manner. NAE 12:0 was 10-20 times more potent an inhibitor of LOX activities than lauric acid (FFA 12:0). Furthermore, treatment of intact Arabidopsis seedlings with NAE 12:0 (but not FFA 12:0) substantially blocked the wound-induced formation of jasmonic acid (JA), suggesting that NAE 12:0 may be used in planta to manipulate oxylipin metabolism. 相似文献
43.
Belay?T.?Ayele Jocelyn?A.?OzgaEmail author Aruna?D.?Wickramarathna Dennis?M.?Reinecke 《Journal of Plant Growth Regulation》2012,31(2):235-252
The role of gibberellins (GAs) during germination and early seedling growth is examined by following the metabolism and transport
of radiolabeled GAs in cotyledon, shoot, and root tissues of pea (Pisum sativum L.) using an aseptic culture system. Mature pea seeds have significant endogenous GA20 levels that fall during germination and early seedling growth, a period when the seedling develops the capacity to transport
GA20 from the cotyledon to the shoot and root of the seedling. Even though cotyledons at 0–2 days after imbibition have appreciable
amounts of GA20, the cotyledons retain the ability to metabolize labeled GA19 to GA20 and express significant levels of PsGA20ox2 message (which encodes a GA biosynthesis enzyme, GA 20-oxidase). The large pool of cotyledonary GA20 likely provides substrate for GA1 synthesis in the cotyledons during germination, as well as for shoots and roots during early seedling growth. The shoots
and roots express GA metabolism genes (PsGA3ox genes which encode GA 3-oxidases for synthesis of bioactive GA1, and PsGA2ox genes which encode GA 2-oxidases for deactivation of GAs to GA29 and GA8), and they develop the capacity to metabolize GAs as necessary for seedling establishment. Auxins also show an interesting
pattern during early seedling growth, with higher levels of 4-chloro-indole-3-acetic acid (4-Cl-IAA) in mature seeds and higher
levels of indole-3-acetic acid (IAA) in young root and shoot tissues. This suggests a changing role for auxins during early
seedling development. 相似文献
44.
45.
Monocytes play an important role in inflammation and atherosclerosis; however, the molecular details underlying these diverse functions are not completely understood. Proteomic analysis of monocytes can provide new insights into their biological role in coronary artery disease (CAD). Twenty angiographically confirmed male, CAD patients (≥50% stenosis) attending cardiology clinic of Nehru Hospital, PGIMER, Chandigarh, and who were not receiving any lipid lowering therapy and 20 TMT negative subjects who served as controls were enrolled in the study. Circulating monocytes isolated from overnight fasting blood samples were analyzed by 2D gel electrophoresis (pH 4-7), and differentially expressed protein spots were subjected to mass spectrometry and identification of proteins. We observed 333 ± 40 protein spots in monocytes from patients and 312 ± 20 in controls; out of which 63 protein spots showed altered intensity in CAD patients. Thirteen spots showed fivefold increased and two protein spots showed fivefold decreased expression in CAD group as compared to control group, respectively. Two proteins showing decreased expression in monocytes from CAD patients were identified as: (i) glutathione transferase and (ii) heat shock protein 70 KDa. Proteins showing increased expression in CAD patients were identified as: (i) vimentin, (ii) mannose binding lectin receptor protein, and (iii) S100A8 calcium-binding protein. The results of our study offer identification of several proteins in monocytes which can provide new perspectives in role of monocytes in pathogenesis of atherosclerosis. 相似文献
46.
Naushad SM Prayaga A Digumarti RR Gottumukkala SR Kutala VK 《Molecular and cellular biochemistry》2012,361(1-2):189-195
In view of recent studies highlighting the prognostic relevance of expression and CpG island methylator phenotype (CIMP) of Bcl-2/adenovirus E1B 19 kDa-interacting protein 3 (BNIP3) in invasive duct cell carcinoma (IDC), we hypothesized in this article that impaired one-carbon metabolism might influence CIMP phenotype of BNIP3. In order to substantiate the prognostic relevance of BNIP3, we explored its association with 8-oxo-2'deoxyguanosine (8-oxodG), a marker of oxidative stress with prognostic relevance. BNIP3 expression and CIMP phenotype were studied using semi-quantitative RT-PCR and combined bisulfite restriction analysis (COBRA), respectively, in 56 IDC tumors. Eight polymorphisms in one-carbon metabolism were studied using PCR-RFLP and PCR-AFLP approaches. 8-oxodG was measured using competitive ELISA kit. BNIP3 was found to be upregulated in IDC (cases vs. controls: 0.94 ± 0.05 vs. 0.18 ± 0.08, P < 0.0001). COBRA analysis confirmed hypomethylation of BNIP3 promoter CpG island in these cases. CIMP phenotype of BNIP3 showed positive association with tubule formation (P = 0.034) and methionine synthase reductase (MTRR) A66G (P = 0.002); inverse association with cytosolic serine hydroxyl methyltransferase (cSHMT) C1420T (P < 0.005) and 8-oxodG (<10% vs. >10% methylation: 7.24 ± 2.77 ng/ml vs. 4.42 ± 2.93 ng/ml, P < 0.0005); and no association with nuclear pleomorphism or mitotic index or ER, PR, and HER statuses. Synergistic effect of MTR A2756G and MTRR A66G variants on BNIP3 hypermethylator phenotype was clearly evident (P < 0.0007). MTRR A66G and cSHMT C1420T polymorphisms influence CIMP phenotype of BNIP3, thus epigenetically regulating BNIP3 in breast cancer. The linear association between BNIP3 and 8-oxodG substantiates the role of BNIP3 as redox sensor as well as prognostic marker in breast cancer. 相似文献
47.
Aruna Govindaraju Alper Uzun LaShonda Robertson Mehmet O Atli Abdullah Kaya Einko Topper Elizabeth A Crate James Padbury Andy Perkins Erdogan Memili 《Reproductive biology and endocrinology : RB&E》2012,10(1):1-10
Background
Degenerative effects of critical regulators of reproduction, the kisspeptin peptides, on cellular aspects of sexually immature male gonads are known but similar information on accessory sex glands remain elusive.Methods
Prepubertal laboratory rats were injected kisspeptin-10 at three different dosage concentrations (10 pg, 1 ng and 1 microgram) for a period of continuous 12 days at the rate of two doses per day. Control rats were maintained in parallel. The day following the end of the experimental period, seminal vesicles were removed and processed for light and electron microscopic examination using the standard methods. DNA damage was estimated by DNA ladder assay and DNA fragmentation assay.Results
The results demonstrated cellular degeneration. Epithelial cell height of seminal vesicles decreased significantly at all doses (P < 0.05). Marked decrease in epithelial folds was readily noticeable, while the lumen was dilated. Ultrastructural changes were characterized by dilatation of endoplasmic reticulum and Golgi complex, heterochromatization of nuclei, invagination of nuclear membranes and a decreased number of secretory granules. Percent DNA damage to the seminal vesicle was 19.54 +/- 1.98, 38.06 +/- 2.09 and 58.18 +/- 2.59 at 10 pg, 1 ng and 1 microgram doses respectively.Conclusion
The study reveals that continuous administration of kisspeptin does not lead to an early maturation but instead severe degeneration of sexually immature seminal vesicles. 相似文献48.
YPK9 (Yeast PARK9; also known as YOR291W) is a non-essential yeast gene predicted by sequence to encode a transmembrane P-type transport ATPase. However, its substrate specificity is unknown. Mutations in the human homolog of YPK9, ATP13A2/PARK9, have been linked to genetic forms of early onset parkinsonism. We previously described a strong genetic interaction between Ypk9 and another Parkinson's disease (PD) protein α-synuclein in multiple model systems, and a role for Ypk9 in manganese detoxification in yeast. In humans, environmental exposure to toxic levels of manganese causes a syndrome similar to PD and is thus an environmental risk factor for the disease. How manganese contributes to neurodegeneration is poorly understood. Here we describe multiple genome-wide screens in yeast aimed at defining the cellular function of Ypk9 and the mechanisms by which it protects cells from manganese toxicity. In physiological conditions, we found that Ypk9 genetically interacts with essential genes involved in cellular trafficking and the cell cycle. Deletion of Ypk9 sensitizes yeast cells to exposure to excess manganese. Using a library of non-essential gene deletions, we screened for additional genes involved in tolerance to excess manganese exposure, discovering several novel pathways involved in manganese homeostasis. We defined the dependence of the deletion strain phenotypes in the presence of manganese on Ypk9, and found that Ypk9 deletion modifies the manganese tolerance of only a subset of strains. These results confirm a role for Ypk9 in manganese homeostasis and illuminates cellular pathways and biological processes in which Ypk9 likely functions. 相似文献
49.
Arujuna A Murphy C Hayat A Seffens H Gill JS 《Indian pacing and electrophysiology journal》2012,12(3):82-92
IntroductionWe describe the use of a ablating system to compartmentalise and regionally isolate the atria in paroxysmal and persistent atrial fibrillation (AF).Methods40 patients were studied, 25 paroxysmal AF and 14 persistent AF. One patient enrolled was later found to be in left atrial flutter and was excluded. The Cardima Revelation® TX catheter system with Intellitemp® Radiofrequency (RF) energy control device and a Medtronic Atakar® RF generator were used to place wide area circumferential ablations to achieve conduction block into the left and right sided pulmonary veins. Roof lines and mitral isthmus lines were also performed. In patients with persistent AF and in repeat procedures, right atrial compartmentalisation was performed with an anterior superior vena cava (SVC) to inferior vena cava (IVC) line and a septal SVC to IVC line.ResultsAt 6 months, 18 of the 39 patients were asymptomatic, 10 had improved symptoms and 22 were in sinus rhythm. In the paroxysmal group, 11 were asymptomatic, 7 had improved symptoms and 16 (64%) were in sinus rhythm. In the persistent group, 7 were asymptomatic, 3 had improved symptoms and 6 (43%) were in sinus rhythm. The total group AF burden was 37.8 ± 5.4 hrs pre-procedure and 23.1 ± 5.1 hrs at 6 months post procedure. Mean temperature, impedance and power recorded at each pole demonstrated effective power delivery at all poles. No catheter charring was observed, complication rates were comparable to standard AF ablation technique.ConclusionLinear ablation in the left and right atria to mimic Cox’s Maze is feasible and safe using this ablating system. 相似文献