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991.
Autophagy Is Modulated in Human Neuroblastoma Cells Through Direct Exposition to Low Frequency Electromagnetic Fields 下载免费PDF全文
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Valeria D’Argenio Eugenio Notomista Mauro Petrillo Piergiuseppe Cantiello Valeria Cafaro Viviana Izzo Barbara Naso Luca Cozzuto Lorenzo Durante Luca Troncone Giovanni Paolella Francesco Salvatore Alberto Di Donato 《BMC genomics》2014,15(1)
Background
Novosphingobium sp. strain PP1Y is a marine α-proteobacterium adapted to grow at the water/fuel oil interface. It exploits the aromatic fraction of fuel oils as a carbon and energy source. PP1Y is able to grow on a wide range of mono-, poly- and heterocyclic aromatic hydrocarbons. Here, we report the complete functional annotation of the whole Novosphingobium genome.Results
PP1Y genome analysis and its comparison with other Sphingomonadal genomes has yielded novel insights into the molecular basis of PP1Y’s phenotypic traits, such as its peculiar ability to encapsulate and degrade the aromatic fraction of fuel oils. In particular, we have identified and dissected several highly specialized metabolic pathways involved in: (i) aromatic hydrocarbon degradation; (ii) resistance to toxic compounds; and (iii) the quorum sensing mechanism.Conclusions
In summary, the unraveling of the entire PP1Y genome sequence has provided important insight into PP1Y metabolism and, most importantly, has opened new perspectives about the possibility of its manipulation for bioremediation purposes.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-384) contains supplementary material, which is available to authorized users. 相似文献995.
Alcaro S Scipione L Ortuso F Posca S Rispoli V Rotiroti D 《Bioorganic & medicinal chemistry letters》2002,12(20):2899-2905
Pivaloyl-choline iodide 1 interactions with acetylcholinesterase (AChE) have been studied by theoretical and enzymatic methods. An integrated computational approach has clearly shown a substrate rather than inhibitory profile for 1. Enzymatic experiments have also supported the same theoretical conclusion indicating that AChE was able to hydrolyze 1 to choline. 相似文献
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Salvatore Chiantia 《生物化学与生物物理学报:生物膜》2009,1788(1):225-838
This review describes the application of fluorescence correlation spectroscopy (FCS) for the study of biological membranes. Monitoring the fluorescence signal fluctuations, it is possible to obtain diffusion constants and concentrations for several membrane components. Focusing the attention on lipid bilayers, we explain the technical difficulties and the new FCS-based methodologies introduced to overcome them. Finally, we report several examples of studies which apply FCS on both model and biological membranes to obtain interesting insight in the topic of lateral membrane organization. 相似文献
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Antonella Caccamo Smita Majumder Janice J. Deng Yidong Bai Fiona B. Thornton Salvatore Oddo 《The Journal of biological chemistry》2009,284(40):27416-27424
TDP-43 is a nuclear protein involved in exon skipping and alternative splicing. Recently, TDP-43 has been identified as the pathological signature protein in frontotemporal lobar degeneration with ubiquitin-positive inclusions and in amyotrophic lateral sclerosis. In addition, TDP-43-positive inclusions are present in Parkinson disease, dementia with Lewy bodies, and 30% of Alzheimer disease cases. Pathological TDP-43 is redistributed from the nucleus to the cytoplasm, where it accumulates. An ∼25-kDa C-terminal fragment of TDP-43 accumulates in affected brain regions, suggesting that it may be involved in the disease pathogenesis. Here, we show that overexpression of the 25-kDa C-terminal fragment is sufficient to cause the mislocalization and cytoplasmic accumulation of endogenous full-length TDP-43 in two different cell lines, thus recapitulating a key biochemical characteristic of TDP-43 proteinopathies. We also found that TDP-43 mislocalization is associated with a reduction in the low molecular mass neurofilament mRNA levels. Notably, we show that the autophagic system plays a role in TDP-43 metabolism. Specifically, we found that autophagy inhibition increases the accumulation of the C-terminal fragments of TDP-43, whereas inhibition of mTOR, a key protein kinase involved in autophagy regulation, reduces the 25-kDa C-terminal fragment accumulation and restores TDP-43 localization. Our results suggest that autophagy induction may be a valid therapeutic target for TDP-43 proteinopathies.TDP-43 (transactive response DNA-binding protein 43) is a conserved and ubiquitously expressed nuclear protein with a theoretical molecular mass of ∼44 kDa. It is encoded by the TARDBP gene on chromosome 1, which is made of six exons that can be alternatively spliced to yield 11 different isoforms, with the mRNA encoding TDP-43 being the major species (1). Functionally, TDP-43 appears to be involved in exon skipping and alternative splicing (2, 3), and it has also been shown to link different types of nuclear bodies (4). Structural studies have confirmed the presence of two RNA recognition motifs (RRM1 and RRM2) and a glycine-rich C-terminal tail, which is thought to mediate protein-protein interaction (5).Recently, TDP-43 has been shown to be the major pathological protein in a wide range of disorders referred to as TDP-43 proteinopathies (6–8). These include frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U),2 motor neuron disease, and amyotrophic lateral sclerosis (ALS). These last two disorders have been directly linked to mutations in TDP-43 (9, 10). In addition, TDP-43-positive inclusions are present in Parkinson disease, dementia with Lewy bodies, and 30% of Alzheimer disease cases (11–14). Sporadic and familial forms of FTLD-U and ALS are characterized by cytoplasmic accumulation of insoluble, hyperphosphorylated, ubiquitinated, and proteolytically cleaved C-terminal fragments in affected brain and spinal cord regions. The cytoplasmic accumulation of TDP-43 is associated with a depletion of nuclear TDP-43 (8, 15–21). These data suggest that some of these TDP-43 proteinopathies may share common mechanisms of pathogenesis.FTLD-U is caused by loss-of-function mutations in the progranulin gene, which lead, by an unknown mechanism, to the accumulation of cytoplasmic TDP-43 inclusions (22, 23). Notably, the TDP-43 inclusions in the ALS and FTLD-U brains are enriched with TDP-43 C-terminal fragments (8, 19). It has been suggested that the C-terminal fragments can be obtained by caspase-dependent cleavage of the full-length protein (24). However, it remains to be established if these fragments play a role in the disease pathogenesis.TDP-43 proteinopathies are characterized by the accumulation of abnormally modified TDP-43, suggesting that dysfunction in the intracellular quality control systems (ubiquitin-proteasome system and the autophagy-lysosome system) may be involved in the disease pathogenesis. The autophagic system is a conserved intracellular system designed for the degradation of long-lived proteins and organelles in lysosomes (25, 26). Three types of autophagy have been described: macroautophagy, microautophagy, and chaperon-mediated autophagy. Whereas macroautophagy and microautophagy involve the “in bulk” degradation of regions of the cytosol (27, 28), chaperon-mediated autophagy is a more selective pathway, and only proteins with a lysosomal targeting sequence are degraded (29). Cumulative evidence has suggested that an age-dependent decrease in the autophagy-lysosome system may account for the accumulation of abnormal proteins during aging (30, 31).Macroautophagy is induced when an isolation membrane is formed surrounding cytosolic components, forming an autophagic vacuole, which will eventually fuse with lysosomes for protein/organelle degradation. Induction of the isolation membrane is negatively regulated by mTOR (mammalian target of rapamycin) (32). It has been shown that increasing autophagy activation by mTOR inhibitors has beneficial effects in neurodegeneration (33–35). 相似文献
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Background and Aims
Species may occur over a wide geographical range within which populations can display large variation in reproductive success and genetic diversity. Neotinea maculata is a rare orchid of conservation concern at the edge of its range in Ireland, where it occurs in small populations. However, it is relatively common throughout the Mediterranean region. Here, factors that affect rarity of N. maculata in Ireland are investigated by comparing Irish populations with those found in Italy, where it is more common.Methods
Vegetation communities, breeding system and genetic diversity were compared using three amplified fragment length polymorphism (AFLP) primer pairs in populations in Ireland and Italy. Vegetation was quantified using quadrats taken along transects in study populations, and hand pollination experiments were performed to assess reliance of N. maculata on pollinators in both Irish and Italian populations.Key Results
Neotinea maculata occupies different vegetation communities in Italian and Irish populations. Breeding system experiments show that N. maculata is 100 % autogamous, and there are no differences in fruit and seed production in selfed, outcrossed and unmanipulated plants. AFLP markers revealed that Irish and Italian populations have similar genetic diversity and are distinct from each other.Conclusions
Neotinea maculata does not suffer any negative effects of autogamous reproduction; it self-pollinates and sets seed readily in the absence of pollinators. It occupies a variety of habitats in both Ireland and Italy; however, Irish populations are small and rare and should be conserved. This could be due to climatic factors and the absence of suitable soil mycorrhizas to allow recruitment from seed.Key words: Neotinea maculata, AFLP, autogamy, conservation, genetic diversity, Lusitanian species, pollination 相似文献999.
In this study we tested the cross-amplification of 33 microsatellite loci previously developed for two closely related Neotropical orchid genera (Epidendrum and Laelia). A set of ten loci were polymorphic across five examined species (20 individuals each) with 2 to 15 alleles per locus. The mean expected and observed heterozygosity (average across species) ranged from 0.34 to 0.82 and from 0.27 to 0.85, respectively. In addition we tested all loci in 35 species representative of the genus Epidendrum. Of these, 26 loci showed successful amplification. Cross-application of these loci represent a potential source of co-dominant markers for evolutionary, ecological and conservation studies in this important orchid genus. 相似文献
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Francesco Massart Francesca Marini Gerolamo Bianchi Salvatore Minisola Giovanni Luisetto Antonella Pirazzoli Sara Salvi Dino Micheli Laura Masi Maria Luisa Brandi 《Reproductive biology and endocrinology : RB&E》2009,7(1):32-8