Induced systemic resistance (ISR) is one of the indirect mechanisms of growth promotion exerted by plant growth-promoting bacteria, and can be mediated by ethylene (ET). We assessed ET production and ...the expression of related genes in the Azospirillum-strawberry plant interaction. Ethylene production was evaluated by gas chromatography in plants inoculated or not with A. brasilense REC3. Also, plants were treated with AgNO
, an inhibitor of ET biosynthesis; with 1-aminocyclopropane-1-carboxylic acid (ACC), a precursor of ET biosynthesis; and with indole acetic acid (IAA). Plant dry biomass and the growth index were determined to assess the growth-promoting effect of A. brasilense REC3 in strawberry plants. Quantitative real time PCR (qRT-PCR) was performed to analyse relative expression of the genes Faetr1, Faers1 and Faein4, which encode ET receptors; Factr1 and Faein2, involved in the ET signalling pathway; Faacs1 encoding ACC synthase; Faaco1 encoding ACC oxidase; and Faaux1 and Faami1 for IAA synthesis enzymes. Results showed that ET acts as a rapid and transient signal in the first 12 h post-treatment. A. brasilense REC3-inoculated plants had a significantly higher growth index compared to control plants. Modulation of the genes Faetr1, Faers1, Faein4, Factr1, Faein2 and Faaco1 indicated activation of ET synthesis and signalling pathways. The up-regulation of Faaux1 and Faami1 involved in IAA synthesis suggested that inoculation with A. brasilense REC3 induces production of this auxin, modulating ET signalling. Ethylene production and up-regulation of genes associated with ET signalling in strawberry plants inoculated with A. brasilense REC3 support the priming activation characteristic of ISR. This type of resistance and the activation of systemic acquired resistance previously observed in this interaction indicate that both are present in strawberry plants, could act synergistically and increase protection against pathogens.
We present a multilocus phylogeny of the class Dacrymycetes, based on data from the 18S, ITS, 28S, RPB1, RPB2, TEF-1α, 12S, and ATP6 DNA regions, with c. 90 species including the types of most ...currently accepted genera. A variety of methodological
approaches was used to infer phylogenetic relationships among the Dacrymycetes, from a supermatrix strategy using maximum likelihood and Bayesian inference on a concatenated dataset, to coalescence-based calculations, such as quartet-based summary methods of independent single-locus
trees, and Bayesian integration of single-locus trees into a species tree under the multispecies coalescent. We evaluate for the first time the taxonomic usefulness of some cytological phenotypic characters, i.e., vacuolar contents (vacuolar bodies and lipid bodies), number of nuclei of recently
discharged basidiospores, and pigments, with especial emphasis on carotenoids. These characters, along with several others traditionally used for the taxonomy of this group (basidium shape, presence and morphology of clamp connections, morphology of the terminal cells of cortical/marginal
hyphae, presence and degree of ramification of the hyphidia), are mapped on the resulting phylogenies and their evolution through the class Dacrymycetes discussed. Our analyses reveal five lineages that putatively represent five different families, four of which are accepted and named.
Three out of these four lineages correspond to previously circumscribed and published families (Cerinomycetaceae, Dacrymycetaceae, and Unilacrymaceae), and one is proposed as the new family Dacryonaemataceae. Provisionally, only a single order, Dacrymycetales,
is accepted with in the class. Furthermore, the systematics of the two smallest families, Dacryonaemataceae and Unilacrymaceae, are investigated to the species level, using coalescence-based species delimitation on multilocus DNA data, and a detailed morphological study including
morphometric analyses of the basidiospores. Three species are accepted in Dacryonaema, the type, Da. rufum, the newly combined Da. macnabbii (basionym Dacrymyces macnabbii), and a new species named Da. macrosporum. Two species are accepted in Unilacryma,
the new U. bispora, and the type, U. unispora, the latter treated in a broad sense pending improved sampling across the Holarctic.
In many lichen-forming fungi, molecular phylogenetic analyses lead to the discovery of cryptic species within traditional morphospecies. However, in some cases, molecular sequence data also questions ...the separation of phenotypically characterised species. Here we apply an integrative
taxonomy approach - including morphological, chemical, molecular, and distributional characters - to re-assess species boundaries in a traditionally speciose group of hair lichens, Bryoria sect. Implexae. We sampled multilocus sequence and microsatellite data from
142 specimens from a broad intercontinental distribution. Molecular data included DNA sequences of the standard fungal markers ITS, IGS, GAPDH, two newly tested loci (FRBi15 and FRBi16), and SSR frequencies from 18 microsatellite markers. Datasets were analysed with Bayesian and maximum
likelihood phylogenetic reconstruction, phenogram reconstruction, STRUCTURE Bayesian clustering, principal coordinate analysis, haplotype network, and several different species delimitation analyses (ABGD, PTP, GMYC, and DISSECT). Additionally, past population demography and divergence times
are estimated. The different approaches to species recognition do not support the monophyly of the 11 currently accepted morphospecies, and rather suggest the reduction of these to four phylogenetic species. Moreover, three of these are relatively recent in origin and cryptic, including phenotypically
and chemically variable specimens. Issues regarding the integration of an evolutionary perspective into taxonomic conclusions in species complexes, which have undergone recent diversification, are discussed. The four accepted species, all epitypified by sequenced material, are Bryoria fuscescens,
B. glabra, B. kockiana, and B. pseudofuscescens. Ten species rank names are reduced to synonymy. In the absence of molecular data, they can be recorded as the B. fuscescens complex. Intraspecific phenotype plasticity and factors affecting the speciation of different
morphospecies in this group of Bryoria are outlined.
The class Myxomycetes consists of free-living protists characterised by their complex life cycle, which includes both microscopic (amoebae, flagellates and cists) and macroscopic stages ...(spore-bearing fruiting bodies, sclerotia, andplasmodia). Withinit, theorder Physarales,
with more than 450 recognised species, constitutes the largest group. Although previous studies have shown the polyphyly of some of the traditionally accepted genera, its internal phylogenetic relationships have remained uncertain so far, and together with the lack of data for some keyspecies,
itprevented any taxonomic and nomenclatural revisions. We have compiled a substantially expanded data setinterms of both taxon sampling and molecular data, including most of the genera described to date and four unlinked DNA regions, for which we provide partial sequences: nSSU, EF-1α
, α-Tub, and mtSSU, analysed through maximum likelihood and Bayesian methods. Our results confirm that the family Didymiaceae is paraphyletic to the rest of Physarales. Within Didymiaceae s. lat., the recent reinstatement of the genus Polyschismium
for most species traditionally ascribed to Lepidoderma, except for the type (Ronikieretal.2022), is further supported here, as well as the definite inclusion of the genus Mucilago in Didymium and Lepidoderma s. str.(L. tigrinum) in Diderma
(Prikhodkoetal.2023). Additionally, thegenus Diachea is redefined to include some species previously treated in Physaraceae (Craterium spp. with true columella). Within the monophyletic family Physaraceae, most genera are recovered as polyphyletic, suggesting that
they should be no longer accepted as currently defined. However, the lack of resolution of some relationships within Physaraceae prevents us from resuscitating or creating several new genera to mitigate polyphyly. Among the well-defined groups with clear molecular signatures, we propose
two taxonomic and nomenclatural changes at generic level:1) a new genus, Nannengaella, is proposed for a major clade containing Physarum globuliferum and other species with heavily calcified sporophores and, often, a true calcareous columella;2) Lignydium is resurrected
for the clade containing Fuligo muscorum. Additionally, Trichamphora is suggested as the correct name for the clade containing Physarum pezizoideum. The taxonomy and nomenclature of some provisional genera, currently synonymous with Fuligo and Physarum, are
disentangled, and we provide a comprehensive and updated nomenclatural conspectus that can be used when better resolved phylogenies are obtained. In total, 22 new combinations are proposed in different genera. Aprovisional key to the genera of the order is also provided.
Context. Debris disks are the natural by-products of the planet formation process. Scattered or polarized light observations are mostly sensitive to small dust grains that are released from the ...grinding down of bigger planetesimals. Aims. High angular resolution observations at optical wavelengths can provide key constraints on the radial and azimuthal distribution of the small dust grains. These constraints can help us better understand where most of the dust grains are released upon collisions. Methods. We present SPHERE/ZIMPOL observations of the debris disk around HR 4796 A, and we modeled the radial profiles along several azimuthal angles of the disk with a code that accounts for the effect of stellar radiation pressure. This enabled us to derive an appropriate description for the radial and azimuthal distribution of the small dust grains. Results. Even though we only modeled the radial profiles along, or close to, the semi-major axis of the disk, our best-fit model is not only in good agreement with our observations but also with previously published datasets (from near-infrared to sub-mm wavelengths). We find that the reference radius is located at 76.4 ± 0.4 au, and the disk has an eccentricity of 0.076−0.010+0.016 $0.076_{-0.010}^{+0.016}$ 0.076−0.010+0.016 with the pericenter located on the front side of the disk (north of the star). We find that small dust grains must be preferentially released near the pericenter to explain the observed brightness asymmetry. Conclusions. Even though parent bodies spend more time near the apocenter, the brightness asymmetry implies that collisions happen more frequently near the pericenter of the disk. Our model can successfully reproduce the shape of the outer edge of the disk without requiring an outer planet shaping the debris disk. With a simple treatment for the effect of the radiation pressure, we conclude that the parent planetesimals are located in a narrow ring of about 3.6 au in width.
There is currently no consensus on how humans are affecting the marine nitrogen (N) cycle, which limits marine biological production and CO2 uptake. Anthropogenic changes in ocean warming, ...deoxygenation, and atmospheric N deposition can all individually affect the marine N cycle and the oceanic production of the greenhouse gas nitrous oxide (N2O). However, the combined effect of these perturbations on marine N cycling, ocean productivity, and marine N2O production is poorly understood. Here we use an Earth system model of intermediate complexity to investigate the combined effects of estimated 21st century CO2 atmospheric forcing and atmospheric N deposition. Our simulations suggest that anthropogenic perturbations cause only a small imbalance to the N cycle relative to preindustrial conditions (∼+5 Tg N y−1 in 2100). More N loss from water column denitrification in expanded oxygen minimum zones (OMZs) is counteracted by less benthic denitrification, due to the stratification‐induced reduction in organic matter export. The larger atmospheric N load is offset by reduced N inputs by marine N2 fixation. Our model predicts a decline in oceanic N2O emissions by 2100. This is induced by the decrease in organic matter export and associated N2O production and by the anthropogenically driven changes in ocean circulation and atmospheric N2O concentrations. After comprehensively accounting for a series of complex physical‐biogeochemical interactions, this study suggests that N flux imbalances are limited by biogeochemical feedbacks that help stabilize the marine N inventory against anthropogenic changes. These findings support the hypothesis that strong negative feedbacks regulate the marine N inventory on centennial time scales.
Key Points
Negative nitrogen cycle feedbacks reduce anthropogenic perturbations
Oceanic N2O emissions are predicted to decline by 2100
Anthropogenically driven changes in ocean circulation and atmospheric N deposition combine to intensify OMZs
Abstract
STUDY QUESTION
Are the levels of total circulating cell-derived microparticles (cMPs) and circulating tissue factor-containing microparticles (cMP-TF) increased in patients with ...endometriosis?
SUMMARY ANSWER
The levels of total cMP, but not cMP-TF, were higher in patients with endometriosis, and these were attributed to higher levels in patients with deep infiltrating endometriosis (DIE).
WHAT IS KNOWN ALREADY
Previous studies have reported elevated levels of total cMP in inflammatory conditions as well as higher levels of other inflammatory biomarkers in endometriosis. Increased expression of tissue factor (a transmembrane receptor for Factor VII/VIIa) in eutopic and ectopic endometrium from patients with endometriosis has been described. There is no previous data regarding total cMP and cMP-TF levels in patients with endometriosis.
STUDY DESIGN, SIZE, DURATION
A prospective case–control study including two groups of patients was carried out. The E group included 65 patients with surgically confirmed endometriosis (37 with DIE lesions) and the C group comprises 33 women without surgical findings of any form of endometriosis. Patients and controls were recruited during the same 10-month period. Controls were the next patient without endometriosis undergoing surgery, after including two patients with endometriosis.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Venous blood samples for total cMP and cMP-TF determinations were obtained at the time of surgery, before anesthesia at a tertiary care center. To assess total cMP, an ELISA functional assay was used and cMP-TF activity in plasma was measured using an ELISA kit.
MAIN RESULTS AND THE ROLE OF CHANCE
Total cMP levels in plasma were higher in the E group compared with the C group (P < 0.0001). The subanalysis of endometriosis patients with DIE or with ovarian endometriomas without DIE showed that total cMP levels were higher in the DIE group (P = 0.001). There were no statistically significant differences in cMP-TF levels among the groups analyzed.
LIMITATIONS, REASONS FOR CAUTION
This is a preliminary study in which the sample size was arbitrarily decided, albeit in keeping with previous studies analyzing cMP in other inflammatory diseases and other biomarkers in endometriosis. The control group included patients with other pathologies as well as healthy controls, and blood samples were taken at different phases of the cycle.
WIDER IMPLICATIONS OF THE FINDINGS
Elevated total cMP levels in DIE patients may reflect an inflammatory and/or procoagulant systemic status in these patients. Further studies are warranted to confirm our findings and to assess the role of cMP levels in the pathophysiology of DIE.
STUDY FUNDING/COMPETING INTEREST(S)
This study was supported in part by a grant from FIS-PI11/01560 and FIS-PI11/00977 within the ‘Plan Nacional de I + D + I’ and co-funded by the ‘ISCIII-Subdirección General de Evaluación’ and ‘Fondo Europeo de Desarrollo Regional (FEDER)’ and by the grant ‘Premi Fi de Residència Emili Letang 2015’ from the Hospital Clínic of Barcelona. The authors have no competing interests to disclose.
Acremonium strictum Elicitor Subtilisin (AsES) is a fungal elicitor that activates innate immunity, conferring disease resistance in strawberry (Fragaria × ananassa Duch.), Arabidopsis and other ...plant species. The aim of the present work was to evaluate the involvement of the ethylene (ET) signalling pathway in AsES‐mediated immune response in strawberry.
Ethylene production and expression of the genes responsible for ET synthesis, perception and response were measured after AsES treatment. ROS (H2O2) accumulation and immunity induced by AsES were studied after ET perception was blocked by 1‐methylcyclopropene (1‐MCP).
Biochemical and molecular results showed that AsES induced a marked increase in local and systemic biosynthesis of ET, both in a biphasic manner. Blocking of ET perception by 1‐MCP prior to AsES induction reduced production of ROS (H2O2) and prevented AsES from eliciting defence against fungal pathogens having different lifestyles, such as Botrytis cinerea (necrotrophic) and Colletotrichum acutatum (hemibiotrophic).
These findings contribute to elucidate the mode of action of the novel elicitor subtilase, AsES, specifically regarding the role of ET signalling in the activation of plant innate immunity, in addition to the multitude of processes regulated by ET in plants.
The novel protein elicitor AsES activates defense responses against Botrytis and Colletotrichum through the ethylene signaling pathway.
Myelofibrosis (MF) occurs as part of the natural history of polycythemia vera (PV) and essential thrombocythemia (ET), and remarkably shortens survival. Although JAK2V617F and CALR allele burden are ...the main transformation risk factors, inflammation plays a critical role by driving clonal expansion toward end-stage disease. NF-κB is a key mediator of inflammation-induced carcinogenesis. Here, we explored the involvement of miR-146a, a brake in NF-κB signaling, in MPN susceptibility and progression. rs2910164 and rs2431697, that affect miR-146a expression, were analyzed in 967 MPN (320 PV/333 ET/314 MF) patients and 600 controls. We found that rs2431697 TT genotype was associated with MF, particularly with post-PV/ET MF (HR = 1.5; p < 0.05). Among 232 PV/ET patients (follow-up time=8.5 years), 18 (7.8%) progressed to MF, being MF-free-survival shorter for rs2431697 TT than CC + CT patients (p = 0.01). Multivariate analysis identified TT genotype as independent predictor of MF progression. In addition, TT (vs. CC + CT) patients showed increased plasma inflammatory cytokines. Finally, miR-146a
mice showed significantly higher Stat3 activity with aging, parallel to the development of the MF-like phenotype. In conclusion, we demonstrated that rs2431697 TT genotype is an early predictor of MF progression independent of the JAK2V617F allele burden. Low levels of miR-146a contribute to the MF phenotype by increasing Stat3 signaling.
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