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841.
842.
Mariana L. Martín Leandra Lechner Eduardo J. Zabaleta Graciela L. Salerno 《Planta》2013,237(3):813-822
Recent findings demonstrate that alkaline/neutral invertases (A/N-Invs), enzymes that catalyze the breakdown of sucrose into glucose and fructose, are essential proteins in plant life. The fact that different isoforms are present in multiple locations makes them candidates for the coordination of metabolic processes. In the present study, we functionally characterized the encoding gene of a novel A/N-Inv (named A/N-InvC) from Arabidopsis, which localizes in mitochondria. A/N-InvC is expressed in roots, in aerial parts (shoots and leaves) and flowers. A detailed phenotypic analysis of knockout mutant plants (invc) reveals an impaired growth phenotype. Shoot growth was severely reduced, but root development was not affected as reported for A/N-InvA mutant (inva) plants. Remarkably, germination and flowering, two energy demanding processes, were the most affected stages. The effect of exogenous growth regulators led us to suggest that A/N-InvC may be modulating hormone balance in relation to the radicle emergence. We also show that oxygen consumption is reduced in inva and invc in comparison with wild-type plants, indicating that both organelle isoenzymes may play a fundamental role in mitochondrion functionality. Taken together, our results emphasize the involvement of mitochondrial A/N-Invs in developmental processes and uncover the possibility of playing different roles for the two isoforms located in the organelle. 相似文献
843.
844.
Claire Booyjz̈sen Charlotte A. Scarff Ben Moreton Ian Portman James H. Scrivens Giovanni Costantini Peter J. Sadler 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012,1820(3):427-436
BackgroundThe nature of fibrillar deposits from aqueous solutions of human serum and recombinant human transferrin on mica and carbon-coated formvar surfaces has been investigated.Methods and ResultsAtomic force microscopy showed that the deposition of recombinant transferrin onto the hydrophilic surface of mica resulted in the formation of a monolayer-thick film composed of conformationally-strained flattened protein molecules. Elongated fibres developed on top of this layer and appeared to be composed of single proteins or small clusters thereof. Monomeric and dimeric transferrins were separated by gel permeation chromatography and their states of aggregation confirmed by mass spectrometry and dynamic light scattering. Transmission electron-microscopy showed that dimeric transferrin, but not monomeric transferrin, deposited on carbon-coated formvar grids forms rounded (circular) structures ca. 250 nm in diameter. Small transferrin fibrils ca. 250 nm long appeared to be composed of smaller rounded sub-units. Synchrotron radiation-circular dichroism and, Congo red and thioflavin-T dye-binding experiments suggested that transferrin aggregation in solution does not involve major structural changes to the protein or formation of classical β-sheet amyloid structures. Collisional cross sections determined via ion mobility–mass spectrometry showed little difference between the overall protein shapes of apo- and holo-transferrin in the gas phase.General significanceThe possibility that transferrin deformation and aggregation are involved in neurological disorders such as Parkinson's and Alzheimer's disease is discussed. This article is part of a Special Issue entitled Transferrins: Molecular mechanisms of iron transport and disorders. 相似文献
846.
In a review of 19 years'' experience with inhalation of foreign bodies by children the 33 patients (mean age 28 months) were found to have presented most frequently with wheezing or coughing, or both, of recent onset, and to have decreased air entry, rhonchi or respiratory stridor, or a combination of these signs. Eighteen children had inhaled a nut, a pea or a bean. The other 15 had inhaled various organic and inorganic objects. All the children underwent bronchoscopy, and the foreign body was completely removed in 19 during the first procedure; the remainder required repeated bronchoscopy or direct surgical removal of the foreign body, or both. Permanent disability or death was not encountered. The findingsof the study indicate that early bronchoscopic removal is the preferred treatment when a child inhales a foreign body. 相似文献
847.
Monda Hiarhi Cozzolino Vincenza Vinci Giovanni Drosos Marios Savy Davide Piccolo Alessandro 《Plant and Soil》2018,429(1-2):407-424
Plant and Soil - The use of composted agricultural wastes as source of biostimulant compounds provides an added value to the recycling of biomasses. This study aims to expand the knowledge on the... 相似文献
848.
Gabriele Murineddu Francesco Deligia Giulio Ragusa Laura García-Toscano María Gómez-Cañas Battistina Asproni Valentina Satta Elena Cichero Ruth Pazos Paola Fossa Giovanni Loriga Javier Fernández-Ruiz Gerard A. Pinna 《Bioorganic & medicinal chemistry》2018,26(1):295-307
A series of sulfenamide and sulfonamide derivatives was synthesized and evaluated for the affinity at CB1 and CB2 receptors. The N-bornyl-S-(5,6-di-p-tolylpyridazin-3-yl)-sulfenamide, compound 11, displayed good affinity and high selectivity for CB1 receptors (Ki values of 44.6?nM for CB1 receptors and >40?μM for CB2 receptors, respectively). The N-isopinocampheyl-sulfenamide 12 and its sulfonamide analogue 22 showed similar selectivity for CB1 receptors with Ki values of 75.5 and 73.2?nM, respectively. These novel compounds behave as antagonists/inverse agonists at CB1 receptor in the [35S]-GTPγS binding assays, and none showed adequate predictive blood–brain barrier permeation, exhibiting low estimated LD50. However, testing compound 12 in a supraspinal analgesic test (hot-plate) revealed that it was as effective as the classic CB1 receptor antagonist rimonabant, in reversing the analgesic effect of a cannabinoid agonist. 相似文献
849.
Elisabetta Barresi Chiara Giacomelli Simona Daniele Ilaria Tonazzini Marco Robello Silvia Salerno Ilaria Piano Barbara Cosimelli Giovanni Greco Federico Da Settimo Claudia Martini Maria Letizia Trincavelli Sabrina Taliani 《Bioorganic & medicinal chemistry》2018,26(22):5885-5895
The expression levels and the subcellular localization of adenosine receptors (ARs) are affected in several pathological conditions as a consequence of changes in adenosine release and metabolism. In this respect, labelled probes able to monitor the AR expression could be a useful tool to investigate different pathological conditions. Herein, novel ligands for ARs, bearing the fluorescent 7-nitrobenzofurazan (NBD) group linked to the N1 (1,2) or N10 (3,4) nitrogen of a triazinobenzimidazole scaffold, were synthesized. The compounds were biologically evaluated as fluorescent probes for labelling A1 and A2B AR subtypes in bone marrow-derived mesenchymal stem cells (BM-MSCs) that express both receptor subtypes. The binding affinity of the synthetized compounds towards the different AR subtypes was determined. The probe 3 revealed a higher affinity to A1 and A2B ARs, showing interesting spectroscopic properties, and it was selected as the most suitable candidate to label both AR subtypes in undifferentiated MSCs.Fluorescence confocal microscopy showed that compound 3 significantly labelled ARs on cell membranes and the fluorescence signal was decreased by the cell pre-incubation with the A1 AR and A2B AR selective agonists, R-PIA and BAY 60-6583, respectively, thus confirming the specificity of the obtained signal. In conclusion, compound 3 could represent a useful tool to investigate the expression pattern of both A1 and A2B ARs in different pathological and physiological processes. Furthermore, these results provide an important basis for the design of new and more selective derivatives able to monitor the expression and localization of each different ARs in several tissues and living cells. 相似文献
850.
Eric van de Weg Mario Di Guardo Melanie Jänsch Didier Socquet-Juglard Fabrizio Costa Isabelle Baumgartner Giovanni A. L. Broggini Markus Kellerhals Michela Troggio François Laurens Charles-Eric Durel Andrea Patocchi 《Molecular breeding : new strategies in plant improvement》2018,38(1):5
Most cultivated apple cultivars are highly susceptible to fire blight, caused by Erwinia amylovora. However, differences in resistance levels are observed among cultivars and could be used in breeding. In this paper, we investigated the genetic basis of fire blight resistance of the cultivar ‘Enterprise’ and the advanced breeding selection X-6398. Genotyped pedigrees were used for validating and curating historic pedigree records. Various quantitative trait locus (QTL) discovery approaches were applied on the full-sib families ‘Gala’ × ‘Enterprise’ (GaEn) and X-6398 × X-6683 (IW) with the software FlexQTL? and MapQTL®. The paternal lineage of ‘Enterprise’ was reconstructed and showed to include ‘Cox’s Orange Pippin’. The QTLs found varied with the software used. Using FlexQTL?, two were found on linkage groups (LGs) 7 and 13, favourable alleles inherited by Enterprise from ‘Cox’s Orange Pippin’ and ‘Golden Delicious’, respectively. The former was identical to the previously named FB_F7 allele from ‘Fiesta’, while the latter is new and has been named FB_13GD. X-6398 had a QTL at the same position as FB_F7. Its favourable allele was new, originating from the unknown grandfather of X-4598, and was named FB_7X-6398. Using MapQTL® on GaEn, FB_F7 was also identified. Performing the same analysis on the subset of offspring that carried the favourable allele of FB_F7, two putative QTLs on LG8 and on top of LG13 were identified, which showed interactions with FB_F7. Implication of the findings for breeding for fire blight-resistant apples is discussed. Single nucleotide polymorphism data on Enterprise and its ancestors are provided. 相似文献