85 research outputs found
EM Decay of X(3872) as the charmonium
The recently BaBar results raise the possibility that X(3872) has negative
parity. This makes people reconsider assigning X(3872) to the state. In this paper we give a general form of the wave function of
mesons. By solving the instantaneous Bethe-Salpeter equation, we get
the mass spectrum and corresponding wave functions. We calculate
electromagnetic decay widths of the first state which we assume to be
the X(3872) particle. The results are keV, eV and keV. The ratio of branch fractions
of the second and first channel is about 0.002, which is inconsistent with the
experimental value . So X(3872) is unlikely to be a
charmonium state. In addition, we obtain a relatively large decay width for
channel which is keV.Comment: Revised versio
Issues and Opportunities in Exotic Hadrons
The last few years have been witness to a proliferation of new results
concerning heavy exotic hadrons. Experimentally, many new signals have been
discovered that could be pointing towards the existence of tetraquarks,
pentaquarks, and other exotic configurations of quarks and gluons.
Theoretically, advances in lattice field theory techniques place us at the cusp
of understanding complex coupled-channel phenomena, modelling grows more
sophisticated, and effective field theories are being applied to an ever
greater range of situations. It is thus an opportune time to evaluate the
status of the field. In the following, a series of high priority experimental
and theoretical issues concerning heavy exotic hadrons is presented.Comment: White paper from INT workshop, "Modern Exotic Hadrons". References
added. Version to appear in Chinese Physics
Electro-enzymatic ATP regeneration coupled to biocatalytic phosphorylation reactions
Funding Information: A.L.D, M.P. and M.V. thank grants RTI2018-095090-B-I00 and PID2021-1241160B-I00 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union, and 2021AEP014 funded by CSIC. G.G.M. thanks grant BES-2016-078815 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union. I.L.-M. and M.V. acknowledge financial support through grant S2018/BAA-4403 SINOXPHOS-CM (EU-FEDER). I.A.C.P. and A.M.C. thank support from the Fundação para a Ciência e Tecnologia through fellowship SFRH/BD/146475/2019 and MOSTMICRO-ITQB R&D Unit (UIDB/04612/2020, UIDP/04612/2020) and LS4FUTURE Associated Laboratory (LA/P/0087/2020). Publisher Copyright: © 2023 The Author(s)Adenosine-5-triphosphate (ATP) is the main energy vector in biological systems, thus its regeneration is an important issue for the application of many enzymes of interest in biocatalysis and synthetic biology. We have developed an electroenzymatic ATP regeneration system consisting in a gold electrode modified with a floating phospholipid bilayer that allows coupling the catalytic activity of two membrane-bound enzymes: NiFeSe hydrogenase from Desulfovibrio vulgaris and F1Fo-ATP synthase from Escherichia coli. Thus, H2 is used as a fuel for producing ATP. This electro-enzymatic assembly is studied as ATP regeneration system of phosphorylation reactions catalysed by kinases, such as hexokinase and NAD+-kinase for respectively producing glucose-6-phosphate and NADP+.publishersversionpublishe
Upregulation of Haploinsufficient Gene Expression in the Brain by Targeting a Long Non-coding RNA Improves Seizure Phenotype in a Model of Dravet Syndrome
AbstractDravet syndrome is a devastating genetic brain disorder caused by heterozygous loss-of-function mutation in the voltage-gated sodium channel gene SCN1A. There are currently no treatments, but the upregulation of SCN1A healthy allele represents an appealing therapeutic strategy. In this study we identified a novel, evolutionary conserved mechanism controlling the expression of SCN1A that is mediated by an antisense non-coding RNA (SCN1ANAT). Using oligonucleotide-based compounds (AntagoNATs) targeting SCN1ANAT we were able to induce specific upregulation of SCN1A both in vitro and in vivo, in the brain of Dravet knock-in mouse model and a non-human primate. AntagoNAT-mediated upregulation of Scn1a in postnatal Dravet mice led to significant improvements in seizure phenotype and excitability of hippocampal interneurons. These results further elucidate the pathophysiology of Dravet syndrome and outline a possible new approach for the treatment of this and other genetic disorders with similar etiology
System-based proteomic analysis of the interferon response in human liver cells
BACKGROUND: Interferons (IFNs) play a critical role in the host antiviral defense and are an essential component of current therapies against hepatitis C virus (HCV), a major cause of liver disease worldwide. To examine liver-specific responses to IFN and begin to elucidate the mechanisms of IFN inhibition of virus replication, we performed a global quantitative proteomic analysis in a human hepatoma cell line (Huh7) in the presence and absence of IFN treatment using the isotope-coded affinity tag (ICAT) method and tandem mass spectrometry (MS/MS). RESULTS: In three subcellular fractions from the Huh7 cells treated with IFN (400 IU/ml, 16 h) or mock-treated, we identified more than 1,364 proteins at a threshold that corresponds to less than 5% false-positive error rate. Among these, 54 were induced by IFN and 24 were repressed by more than two-fold, respectively. These IFN-regulated proteins represented multiple cellular functions including antiviral defense, immune response, cell metabolism, signal transduction, cell growth and cellular organization. To analyze this proteomics dataset, we utilized several systems-biology data-mining tools, including Gene Ontology via the GoMiner program and the Cytoscape bioinformatics platform. CONCLUSIONS: Integration of the quantitative proteomics with global protein interaction data using the Cytoscape platform led to the identification of several novel and liver-specific key regulatory components of the IFN response, which may be important in regulating the interplay between HCV, interferon and the host response to virus infection
The sulfur pathway and diagnosis of sulfate depletion in grapevine
Sulfur is an essential nutrient to all plant species. Plants assimilate sulfur
in a well-described pathway, which has been taken up by roots. Regulatory mech-
anism has been the subject of many research papers. However, recent studies
highlighted differences between crop plants and the model plant Arabidopsis
thaliana. Our work focuses on the identification of genes involved in the sulfur
metabolism in the Vitis vinifera genome, and their response to sulfur deficiency and
other abiotic stress endured by grapevine in the field, namely water stress. Here, we
describe the identification and brief characterization of the first assimilation
enzymes involved in the sulfur pathway, the enzyme responsible for sulfur activa-
tion, ATP sulfurylase (ATPS), and the two enzymes that reduce sulfate to sulfide,
Adenosine 50-phosphosulate reductase (APR) and Sulfite reductase (SiR). A reduc-
tion was observed in the number of ATPS and APR isoforms identified in
V. vinifera genome when compared to A. thaliana or Glycine max genomes. Two
ATPS isoforms were present in the Vitis genome, of which only ATPS1 transcript
was detected in the tested tissues, and one APR isoform, suggesting an absence of
redundancy in the role of both enzymes. ATPS1, APR and SiR transcript level was
up-regulated in response to 2 days exposure to sulfur deficiency in V. vinifera cell
cultures, which was completely reversed by the addition of GSH to the culture
medium. Apparently, oxidative stress triggered GSH has a pivotal role in the
regulation of ATPS1, APR and SiR transcription level, since their up-regulation
was observed in mRNA from field grapevine berries under water stress, which is
known to induce oxidative stress.info:eu-repo/semantics/publishedVersio
Phenomenology of Pc(4380)+, Pc(4450)+ and related states
The and states recently discovered at LHCb have
masses close to several relevant thresholds, which suggests they can be
described in terms of meson-baryon degrees of freedom. This article explores
the phenomenology of these states, and their possible partners, from this point
of view. Competing models can be distinguished by the masses of the neutral
partners which have yet to be observed, and the existence or otherwise of
further partners with different isospin, spin, and parity. Future experimental
studies in different decay channels can also discriminate among models, using
selection rules and algebraic relations among decays. Among the several
possible meson-baryon pairs which could be important, one implies that the
states are mixtures of isospins 1/2 and 3/2, with characteristic signatures in
production and decay. A previous experimental study of a Cabibbo-suppressed
decay showed no evidence for the states, and further analysis is required to
establish the significance of this non-observation. Several intriguing
similarities suggest that is related to the meson.Comment: 16 pages, 1 figure. Journal version (some very minor changes from
arXiv v1
Heat and water stress induce unique transcriptional signatures of heat-shock proteins and transcription factors in grapevine
Grapevine is an extremely important crop worldwide.
In southern Europe, post-flowering phases of the growth
cycle can occur under high temperatures, excessive light, and
drought conditions at soil and/or atmospheric level. In this
study, we subjected greenhouse grown grapevine, variety
Aragonez, to two individual abiotic stresses, water deficit stress
(WDS), and heat stress (HS). The adaptation of plants to stress
is a complex response triggered by cascades of molecular
networks involved in stress perception, signal transduction,
and the expression of specific stress-related genes and metabolites.
Approaches such as array-based transcript profiling allow
assessing the expression of thousands of genes in control
and stress tissues. Using microarrays, we analyzed the leaf
transcriptomic profile of the grapevine plants. Photosynthesis
measurements verified that the plants were significantly affected
by the stresses applied. Leaf gene expression was obtained
using a high-throughput transcriptomic grapevine array, the
23K custom-made Affymetrix Vitis GeneChip. We identified
1,594 genes as differentially expressed between control and
treatments and grouped them into ten major functional categories
using MapMan software. The transcriptome of Aragonez
was more significantly affected by HS when compared with
WDS. The number of genes coding for heat-shock proteins and
transcription factors expressed solely in response to HS suggesting
their expression as unique signatures of HS. However, a cross-talk between the response pathways to both stresses was
observed at the level of AP2/ERF transcription factors
Reference gene validation for quantitative RT-PCR during biotic and abiotic stresses in Vitis vinifera
Grapevine is one of the most cultivated fruit crop worldwide with Vitis vinifera being the species with the highest
economical importance. Being highly susceptible to fungal pathogens and increasingly affected by environmental factors, it
has become an important agricultural research area, where gene expression analysis plays a fundamental role. Quantitative
reverse transcription polymerase chain reaction (qRT-PCR) is currently amongst the most powerful techniques to perform
gene expression studies. Nevertheless, accurate gene expression quantification strongly relies on appropriate reference
gene selection for sample normalization. Concerning V. vinifera, limited information still exists as for which genes are the
most suitable to be used as reference under particular experimental conditions. In this work, seven candidate genes were
investigated for their stability in grapevine samples referring to four distinct stresses (Erysiphe necator, wounding and UV-C
irradiation in leaves and Phaeomoniella chlamydospora colonization in wood). The expression stability was evaluated using
geNorm, NormFinder and BestKeeper. In all cases, full agreement was not observed for the three methods. To provide
comprehensive rankings integrating the three different programs, for each treatment, a consensus ranking was created
using a non-weighted unsupervised rank aggregation method. According to the last, the three most suitable reference
genes to be used in grapevine leaves, regardless of the stress, are UBC, VAG and PEP. For the P. chlamydospora treatment,
EF1, CYP and UBC were the best scoring genes. Acquaintance of the most suitable reference genes to be used in grapevine
samples can contribute for accurate gene expression quantification in forthcoming studiesinfo:eu-repo/semantics/publishedVersio
- …