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1.
Int J Mol Sci ; 25(9)2024 Apr 29.
Article de Anglais | MEDLINE | ID: mdl-38732085

RÉSUMÉ

Meloidogyne hapla is one of the most important nematode pathogens. It is a sedentary, biotrophic parasite of plants that overwinters in the soil or in diseased roots. The development of M. hapla is temperature dependent. Numerous studies have been performed on the effect of temperature on the development of M. hapla, but only a few of them analyzed the heat shock protein (hsp) genes. The aim of the study was to perform expression profiling of eight hsp genes (Mh-hsp90, Mh-hsp1, Mh-hsp4, Mh-hsp6, Mh-hsp60, Mh-dnj19, Mh-hsp43, and Mh-hsp12.2) at two development stages of M. hapla, i.e., in eggs and second-stage juveniles (J2). The eggs and J2 were incubated under cold stress (5 °C), heat stress (35 °C, 40 °C), and non-stress (10 °C, 20 °C, and 30 °C) conditions. Expression profiling was performed by qPCR. It was demonstrated that only two genes, Mh-hsp60 and Mh-dnj19, have been upregulated by heat and cold stress at both development stages. Heat stress upregulated the expression of more hsp genes than cold stress did. The level of upregulation of most hsp genes was more marked in J2 than in eggs. The obtained results suggest that the Mh-hsp90 and Mh-hsp1 genes can be used as bioindicators of environmental impacts on nematodes of the Meloidogyne genus.


Sujet(s)
Protéines du choc thermique , Tylenchoidea , Tylenchoidea/physiologie , Animaux , Protéines du choc thermique/génétique , Protéines du choc thermique/métabolisme , Température , Protéines d'helminthes/génétique , Protéines d'helminthes/métabolisme , Ovule/métabolisme , Ovule/croissance et développement , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes au cours du développement
2.
Sci Rep ; 13(1): 21268, 2023 12 02.
Article de Anglais | MEDLINE | ID: mdl-38042912

RÉSUMÉ

Betula pendula Roth. is considered a pioneering plant species important for urban ecosystems. Based on the sequencing of fungal ITS, we characterized the ectomycorrhizal (ECM) communities of twenty silver birch trees growing in a contaminated, highly anthropo-pressured urban environment and in a natural reserve site. We analysed chemical properties of each tree soil samples, focusing on effects of anthropogenic transformation. Three effects of urbanization: high heavy metal content, increased salinity and soil alkalinity, were highly correlated. The examined trees were divided into two forest and two urban clusters according to the level of anthropogenic soil change. The effect of soil transformation on the ECM communities was studied, with the assumption that stronger urban transformation leads to lower ECM vitality and diversity. The results of the study did not confirm the above hypothesis. The ECM colonization was above 80% in all clusters, but the forest clusters had significantly higher share of vital non-ECM root tips than the urban ones. Eleven mycorrhizal fungal species were identified varying from seven to nine and with seven species observed in the most contaminated urban plot. However, the lowest Shannon species diversity index was found in the most natural forest cluster. In conclusion, our findings demonstrate no significant negative effect of the urban stresses on the ECM communities of silver birch suggesting that both forest and urban trees have the potential to generate a similar set of ECM taxa.


Sujet(s)
Mycobiome , Mycorhizes , Betula/microbiologie , Sol , Écosystème , Arbres
3.
Int J Mol Sci ; 24(21)2023 Oct 30.
Article de Anglais | MEDLINE | ID: mdl-37958731

RÉSUMÉ

Biodiversity within composting systems involves a variety of microorganisms including nematodes. In the research, nematode populations were monitored within six simultaneously operating composting processes. These processes involved varying proportions of feedstock materials. The primary objective was to evaluate the consistency of nematode community succession patterns across the composting processes over a time of 3 months. During the study, samples were taken every month to isolate nematodes, determine the population density of the five trophic groups (per genus) and determine the dominant nematode species. It was shown that the bacterial-feeding community maintained dominance, while the fungus-feeding nematodes gradually increased in dominance as the maturation process progressed. The presence of predatory nematodes Mononchoides which were initially absent, along with the total absence of parasitic nematodes in the late stages of waste stabilization, serves as strong evidence for the reliable evaluation of the biodegradable waste processing level. Based on the obtained results, it is evident that the succession of nematode communities holds promise as a reliable method for evaluating compost maturity.


Sujet(s)
Compostage , Nematoda , Animaux , Sol , Nematoda/génétique , Biodiversité , Séquençage nucléotidique à haut débit
4.
J Nematol ; 55(1): 20230009, 2023 Feb.
Article de Anglais | MEDLINE | ID: mdl-37082220

RÉSUMÉ

Assuming that the seeds of Vicia sativa L. have a stressful effect on J2 stage Meloidogyne hapla, we undertook research on the effect of these seeds on the motility and mortality of J2 and determined the expression levels of selected hsp genes in J2. The assessment of the effect of V. sativa seeds on the motility of M. hapla specimens consisted of observing the movement of J2 immersed in a seed diffusate or in a tomato root filtrate at temperatures of 10, 17, and 21°C. In J2 treated with V. sativa (cv. Ina) seed diffusates, the expression level of hsp genes was determined by qPCR. J2 exposed to V. sativa diffusates were found to lose their motility, while their mortality did not exceed 30%. J2 in the seed diffusate were characterized by an increase in the expression levels of the Mh-hsp90, Mh-hsp1, and Mh-hsp43 genes. It is suggested that the hsp90 gene may be a potential bioindicator of the environmental impact on Meloidogyne nematodes. The impaired ability to move in J2 of M. hapla is attributable to the occurrence of V. sativa seeds in their habitat. These studies may contribute to developing methods of reducing crop damage caused by M. hapla.

5.
Pathogens ; 10(11)2021 Oct 21.
Article de Anglais | MEDLINE | ID: mdl-34832516

RÉSUMÉ

Ash shoot dieback has now spread throughout Europe. It is caused by an interaction between fungi that attack shoots (Hymenoscyphus fraxineus) and roots (Armillaria spp., in our case Armillaria gallica). While detection of the pathogen is relatively easy when disease symptoms are present, it is virtually impossible when the infestation is latent. Such situations occur in nurseries when seedlings become infected (the spores are carried by the wind several dozen miles). The diseases are masked by pesticides, fertilisers, and adequate irrigation to protect the plants. Root rot that develops in the soil is also difficult to detect. Currently, there is a lack of equipment that can detect root rot pathogens without digging up root systems, which risks damaging trees. For this reason, the use of an electronic nose to detect pathogens in infected tissue of ash trees grown in pots and inoculated with the above fungi was attempted. Disease symptoms were detected in all ash trees exposed to natural infection (via spores) in the forest. The electronic nose was able to detect the pathogens (compared to the control). Detection of the pathogens in seedlings will enable foresters to remove diseased trees and prevent the path from nursery to forest plantations by such selection.

6.
PeerJ ; 9: e12076, 2021.
Article de Anglais | MEDLINE | ID: mdl-34616604

RÉSUMÉ

BACKGROUND: Global warming and drying have markedly enhanced in most forests the risk of fires across the world, which can affect the taxonomic and functional composition of key tree-associated organisms such as ectomycorrhizal (ECM) fungi. The present study was conducted to characterise the alterations in the extent of root ECM colonisation, the ECM fungal communities, and their exploration types (i.e., indicator of ECM soil foraging strategies) in regenerated pines within a burned site as compared with an unburned site (five years after the fire event) in the Forest District Myszyniec, Poland. METHODS: To assess the ECM fungal communities of burned and control sites, soil soil-root monoliths were collected from the study sites in September 2019. A total of 96 soil subsamples were collected for soil analysis and mycorrhizal assessment (6 trees × 2 sites × 4 study plots × 2 microsites (north and south) = 96 subsamples). RESULTS: The percentage of root ECM colonisation was significantly lower in the burned site in comparison with the unburned (control) site. However, the ECM species richness did not differ between the control and burned sites. The identified ECM species in both sites were Imleria badia, Thelephora terrestris, Russula paludosa, R. badia, R. turci, R. vesca, Lactarius plumbeus, Phialocephala fortinii, and Hyaloscypha variabilis. The most frequent species in the burned and control sites were I. badia and T. terrestris, respectively. The relative abundances of contact, medium-distance smooth and long-distance exploration types in the burned site were significantly different from the control site, dominated by the medium-distance exploration type in both sites. The abundance of the long-distance exploration type in the burned site was markedly greater (27%) than that of the control site (14%), suggesting that the fire event had favoured this ECM foraging strategy. The results demonstrated that the fire led to reduced ECM colonisation of Scots pine trees in the burned site whereas the species richness was not affected, which can be attributed to degrees of fire-resistance in the ECM species, survival of ECM propagules in deeper soil layers, and/or continuous entry of spores/propagules of the ECM fungi from the adjacent forests via wind, water run-off or animals.

7.
Plant Dis ; 2021 May 02.
Article de Anglais | MEDLINE | ID: mdl-33934634

RÉSUMÉ

Raspberry (Rubus idaeus L.) and blackberry (Rubus fruticosus L.) are infected by at least 29 viruses, including the Tomato black ring virus (TBRV) (Martin et al. 2013). TBRV belongs to the genus Nepovirus (subgroup B) of the family Secoviridae and is listed as a plant pathogen in over 40 countries. TBRV infects a wide range of herbaceous and woody plants. In Poland, TBRV has been described on the plants of the following species: Tagetes patula, T. erecta, Cucumis sativus, Cucurbita pepo, Lactuca sativa, Solanum tuberosum, S. lycopersicum, Sambucus nigra, and Robinia pseudoacacia (Jonczyk et al. 2004, Hasiów-Jaroszewska et al. 2015). To this date, there is no information on the incidence of TBRV in raspberry and blackberry in Poland. In the spring of 2019, 52 blackberry leaf samples and 408 raspberry leaf samples were collected from 4 plantations located in central Poland. None of the raspberry plants (cvs. Glen Ample, Polka, Sokolica), nor the blackberry plants (cvs. Thornfree, Polar, Gaj, Kotata) exhibited viral symptoms. Enzyme-linked immunosorbent assay (ELISA) was carried out for extracts from the 460 collected leaf samples to detect TBRV using commercial antisera (Loewe Biochemica GmbH, Germany). The results indicated that 9 samples (4 blackberry, 5 raspberry) were infected with TBRV. The isolates of the virus were transferred by sap inoculation and maintained in Nicotiana tabacum cv. Xanthi. Systemic ringspot, necrosis and patterned lines were observed on tobacco leaves. The presence of the virus in tobacco leaf samples was confirmed by reverse transcription PCR (RT-PCR). Total RNA was extracted from all 9 samples using the silica capture (SC) method described originally by Boom et al. (1990) and adapted to the detection of plant viruses by Malinowski (1997). Part of the CP gene was amplified with the CPF (5'-GCCTGTCTCTCTCGCAATG-3') and CPR (5'-AAGGAGCCAAACTGAAATGT-3') primer pair (Hasiów-Jaroszewska et al. 2015). Amplicons of the expected size (763 bp) were obtained for each sample. The amplified products were purified, sequenced in both directions, deposited in GenBank and assigned accession numbers: MT507387 to MT507390 and MT507394 for the isolates from Rubus idaeus and MT507391 to MT507393 and MN954654 for the isolates from Rubus fruticosus, respectively. The 9 newly obtained TBRV CP gene sequences, together with the 25 isolates deposited in GenBank, were aligned by ClustalW. The isolates obtained in this study showed a 99.0-100% nucleotides (nt) and a 98.7-100% amino acids (aa) identity in the part of the CP, respectively. Comparison of the part of the CP of the 4 blackberry and the 5 raspberry TBRV isolates with 25 TBRV isolates available in GenBank showed a 80.6-97.8% nt and a 87.9-99.5% aa identity, respectively. The results of the phylogenetic analysis have revealed that the TBRV isolates obtained in this study are closely related to 3 Polish isolates (AY157994, KR139941, KR139951) and 1 Bioreba ctrl Switzerland isolate (KT923164). These findings are of epidemiological significance due to the fact that TBRV was detected on symptomless Rubus plants, which therefore represent a reservoir of the virus and a threat in case of a symptomatic infection of sensitive cultivars. Accordingly, the results will assist in using appropriate strategies for reducing TBRV incidence in Rubus-growing areas. Moreover, this is, to the best of our knowledge, the first report of TBRV in raspberry and blackberry in Poland.

8.
PLoS One ; 16(4): e0237551, 2021.
Article de Anglais | MEDLINE | ID: mdl-33901193

RÉSUMÉ

The linden tree (Tilia spp.) is a popular tree for landscaping and urban environments in central and northwest European countries, and it is one of the most popular in cities in Poland. Ectomycorrhizal fungi form a symbiosis with many urban tree species and protect the host plant from heavy metals and against salinity. The aim of this study was to characterise the ECM fungal community of urban linden trees along the tree damage gradient. The study was performed on two sites located in the centre of the city of Gdansk, in northern Poland. The vitality assessment of urban linden trees was made according to Roloff's classification. Tree damage classes were related to soil characteristics using principal component analysis. The five ectomycorrhizal fungal species were shared among all four tree damage classes, and Cenococcum geophilum was found to be the most abundant and frequent ectomycorrhizal fungal species in each class. Soil samples collected in the vicinity of trees belonging to the R0 class had significantly lower pH Na, Cl and Pb content than other soils. Our knowledge of ectomycorrhizal communities in urban areas is still limited, and these findings provide new insights into ectomycorrhizal distribution patterns in urban areas.


Sujet(s)
Mycobiome/physiologie , Mycorhizes/classification , Mycorhizes/physiologie , Tilia/microbiologie , Arbres/microbiologie , Ascomycota/classification , Ascomycota/physiologie , Biodiversité , Écosystème , Forêts , Pologne , Sol/composition chimique , Microbiologie du sol , Symbiose/physiologie
9.
Mol Genet Genomics ; 296(2): 259-269, 2021 Mar.
Article de Anglais | MEDLINE | ID: mdl-33169231

RÉSUMÉ

Bursaphelenchus xylophilus is an emerging pathogenic nematode that is responsible for a devastating epidemic of pine wilt disease worldwide, causing severe ecological damage and economic losses to forestry. Two forms of this nematode have been reported, i.e., with strong and weak virulence, commonly referred as virulent and avirulent strains. However, the pathogenicity-related genes of B. xylophilus are not sufficiently characterized. In this study, to find pathogenesis related genes we re-sequenced and compared genomes of two virulent and two avirulent populations. We identified genes affected by genomic variation, and functional annotation of those genes indicated that some of them might play potential roles in pathogenesis. The performed analysis showed that both avirulent populations differed from the virulent ones by 1576 genes with high impact variants. Demonstration of genetic differences between virulent and avirulent strains will provide effective methods to distinguish these two nematode virulence forms at the molecular level. The reported results provide basic information that can facilitate development of a better diagnosis for B. xylophilus isolates/strains which present different levels of virulence and better understanding of the molecular mechanism involved in the development of the PWD.


Sujet(s)
Variation génétique , Rhabditida/génétique , Facteurs de virulence/génétique , Séquençage du génome entier/méthodes , Animaux , Évolution moléculaire , Séquençage nucléotidique à haut débit , Protéines de protozoaire/génétique , Rhabditida/pathogénicité
10.
Zootaxa ; 4742(1): zootaxa.4742.1.7, 2020 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-32230394

RÉSUMÉ

A new species of the genus Pratylenchoides has been described. It was found in Polish Jurassic Highland, in Ojców National Park. Pratylenchoides ojcowensis sp. nov. was isolated from the soil located around tangled roots of Elymus sp. and Trifolium sp. This species is marked by a conical head in both females and males which is not separated from the body contour and has with 4-5 annuli; a relatively short stylet (20.3-21.3 µm females, 17.7-20.9 µm males) with oval knobs directed posteriorly; the dorsal pharyngeal nucleus located anterior to the cardia (the subventral pharyngeal nuclei located posterior; a pharyngeal lobe of length about two body widths (1.8-2.6); a lateral field with 6 lines in the middle part of body and sometimes with partially areolated outer bands; intestinal fasciculi present; round sperm in the spermatheca in females; a female tail with a maximum of 29 annuli, and an annulated tail terminus. The status of the new species has been verifiied by DNA sequencing and phylogenetic analysis of the 28S rDNA region. The results obtained in the study indicated that P. ojcowensis sp. nov. is most related to P. alkani, P. ritteri and P. nevadensis from which is distinguished by the shape of the female head (conoid vs rounded), shorter stylet in females (20.3-21.3 µm vs 22.0-25.0 µm, 21.0-25.0 µm, 22.0-26.0 µm) and differences in 28S rDNA sequences. In addition (as per the original descriptions Yüksel 1977, Sher 1970, Talavera Tobar 1996) it is distinguished from P. alkani by smaller number of male's head annuli (4-5 vs 7-9), from P. ritteri it is distinguished by posteriorly directed stylet knobs (vs directed laterally), from P. nevadensis it is distinguished by oval and posteriorly directed stylet knobs (vs rounded and directed laterally).


Sujet(s)
Nematoda , Tylenchoidea , Animaux , ADN ribosomique , Femelle , Mâle , Phylogenèse , Racines de plante , Pologne
11.
Pharmacol Rep ; 71(4): 636-643, 2019 Aug.
Article de Anglais | MEDLINE | ID: mdl-31176893

RÉSUMÉ

BACKGROUND: The inverse relationship between GnRH transcript level and GABA neurons activity has suggested that GABA at the hypothalamic level may exert a suppressive effect on subsequent steps of the GnRH biosynthesis. In the present study, we analyzed the effects of GABA type A receptor agonist (muscimol) or antagonist (bicuculline) on molecular mechanisms governing GnRH/LH secretion in follicular-phase sheep. METHODS: ELISA technique was used to investigate the effects of muscimol and/or bicuculline on levels of post-translational products of genes encoding GnRH ligand and GnRH receptor (GnRHR) in the preoptic area (POA), anterior (AH) and ventromedial (VMH) hypothalamus, stalk/median eminence (SME), and GnRHR in the anterior pituitary (AP). Real-time PCR was chosen for determination of the effect of drugs on kisspeptin (Kiss 1) mRNA level in POA and VMH including arcuate nucleus (VMH/ARC), and on Kiss1 receptor (Kiss1r) mRNA abundance in POA-hypothalamic structures. These analyses were supplemented by RIA method for measurement of plasma LH concentration. RESULTS: The study demonstrated that muscimol and bicuculline significantly decreased or increased GnRH biosynthesis in all analyzed structures, respectively, and led to analogous changes in plasma LH concentration. Similar muscimol- and bicuculline-related alterations were observed in levels of GnRHR. However, the expression of Kiss 1 and Kiss1r mRNAs in selected POA-hypothalamic areas of either muscimol- and bicuculline-treated animals remained unaltered. CONCLUSIONS: Our data suggest that GABAergic neurotransmission is involved in the regulatory pathways of GnRH/GnRHR biosynthesis and then GnRH/LH release in follicular-phase sheep conceivably via indirect mechanisms that exclude involvement of Kiss 1 neurons.


Sujet(s)
Cycle oestral/métabolisme , Hormone de libération des gonadotrophines/biosynthèse , Axe hypothalamohypophysaire/effets des médicaments et des substances chimiques , Kisspeptines/métabolisme , Récepteurs GABA-A/métabolisme , Récepteurs à la gonadolibérine/biosynthèse , Animaux , Bicuculline/pharmacologie , Femelle , Agonistes du récepteur GABA-A/pharmacologie , Antagonistes du récepteur GABA-A/pharmacologie , Hormone de libération des gonadotrophines/sang , Axe hypothalamohypophysaire/métabolisme , Muscimol/pharmacologie , Neurones/métabolisme , Ovis
12.
Front Immunol ; 9: 1115, 2018.
Article de Anglais | MEDLINE | ID: mdl-29872440

RÉSUMÉ

Silver nanoparticles (AgNPs) are promising new antimicrobial agents against a wide range of skin and mucosal pathogens. However, their interaction with the immune system is currently not fully understood. Dendritic cells (DCs) are crucial during development of T cell-specific responses against bacterial and viral pathogens. We have previously shown that tannic acid-modified silver nanoparticles (TA-AgNPs) consist of a promising microbicide against HSV-2. The aim of this study was to compare the ability of TA-AgNPs or TA-AuNPs of similar sizes (TA-Ag/AuNPs) to induce DCs maturation and activation in the presence of HSV-2 antigens when used at non-toxic doses. First, we used JAWS II DC line to test toxicity, ultrastructure as well as activation markers (MHC I and II, CD40, CD80, CD86, PD-L1) and cytokine production in the presence of TA-Ag/AuNPs. Preparations of HSV-2 treated with nanoparticles (TA-Ag/AuNPs-HSV-2) were further used to investigate HSV-2 antigen uptake, activation markers, TLR9 expression, and cytokine production. Additionally, we accessed proliferation and activation of HSV-2-specific T cells by DCs treated with TA-AgNP/AuNPs-HSV-2. We found that both TA-AgNPs and TA-AuNPs were efficiently internalized by DCs and induced activated ultrastructure. Although TA-AgNPs were more toxic than TA-AuNPs in corresponding sizes, they were also more potent stimulators of DCs maturation and TLR9 expression. TA-Ag/AuNPs-HSV-2 helped to overcome inhibition of DCs maturation by live or inactivated virus through up-regulation of MHC II and CD86 and down-regulation of CD80 expression. Down-regulation of CD40 expression in HSV-2-infected DCs was reversed when HSV-2 was treated with TA-NPs sized >30 nm. On the other hand, small-sized TA-AgNPs helped to better internalize HSV-2 antigens. HSV-2 treated with both types of NPs stimulated activation of JAWS II and memory CD8+ T cells, while TA-AgNPs treatment induced IFN-γ producing CD4+ and CD8+ T cells. Our study shows that TA-AgNPs or TA-AuNPs are good activators of DCs, albeit their final effect upon maturation and activation may be metal and size dependent. We conclude that TA-Ag/AuNPs consist of a novel class of nano-adjuvants, which can help to overcome virus-induced suppression of DCs activation.


Sujet(s)
Cellules dendritiques/immunologie , Or , Nanoparticules métalliques , Argent , Tanins , Animaux , Marqueurs biologiques , Lignée cellulaire , Chlorocebus aethiops , Cytokines/métabolisme , Cellules dendritiques/métabolisme , Cellules dendritiques/ultrastructure , Expression des gènes , Or/composition chimique , Herpèsvirus humain de type 2/immunologie , Immunophénotypage , Activation des lymphocytes/génétique , Activation des lymphocytes/immunologie , Nanoparticules métalliques/composition chimique , Nanoparticules métalliques/ultrastructure , Souris , Argent/composition chimique , Lymphocytes T/immunologie , Lymphocytes T/métabolisme , Tanins/composition chimique
13.
Inflamm Res ; 66(8): 679-690, 2017 Aug.
Article de Anglais | MEDLINE | ID: mdl-28434120

RÉSUMÉ

OBJECTIVE AND DESIGN: The aim of this study was to elucidate the role of apoptosis mediated through Fas/FasL pathway using the mouse model of atopic dermatitis (AD). MATERIALS AND TREATMENT: AD was induced by epicutaneous application of ovalbumin (OVA) in wild-type C57BL/6, B6. MRL-Faslpr/J (Fas-) and B6Smn.C3-Faslgld/J (FasL-) mouse strains. METHODS: Skin samples were subjected to staining for Fas/FasL expression, M30 epitope and assessment of inflammatory response via immunohistochemical staining. Cytokine and chemokine production was assessed by real-time PCR. RESULTS: In comparison to wild-type mice, OVA sensitization of Fas- and FasL-deficient mice led to increased epidermal and dermal thickness, collagen deposition and local inflammation consisting of macrophages, neutrophils and CD4+ T cells. Fas- and FasL-deficient mice showed increased total counts of regulatory T cells (Tregs) and IgE levels in blood as well as increased expression of IL-1ß, IL-4, IL-5, IL-13 and TGF-1ß mRNA in comparison to wild-type mice. On the other hand, expression of CXCL9 and CXCL10, IL-17 mRNAs in the skin samples in Fas- and FasL-deficient mice was decreased. CONCLUSIONS: Our results show that lack of the Fas-induced apoptosis leads to exacerbation of AD characteristics such as Th2 inflammation and dermal thickening. Therefore, Fas receptor can play an important role in AD pathogenesis by controlling development of the local inflammation.


Sujet(s)
Eczéma atopique/immunologie , Ligand de Fas/immunologie , Antigènes CD95/immunologie , Allergènes , Animaux , Lymphocytes T CD4+/immunologie , Collagène/métabolisme , Cytokines/génétique , Eczéma atopique/sang , Eczéma atopique/génétique , Eczéma atopique/anatomopathologie , Modèles animaux de maladie humaine , Ligand de Fas/génétique , Femelle , Immunoglobuline E/sang , Macrophages/immunologie , Mâle , Souris de lignée C57BL , Souris transgéniques , Granulocytes neutrophiles/immunologie , Ovalbumine , Peau/immunologie , Peau/métabolisme , Peau/anatomopathologie , Antigènes CD95/génétique
14.
Zootaxa ; 4083(2): 297-300, 2016 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-27394233

RÉSUMÉ

Identification of nematode species by using conventional methods requires fixation of the isolated material and a suitable preparation for further analyses. Tentative identification using microscopic methods should also be performed prior to initiating molecular studies. In the literature, various methods are described for the preparation of nematodes from the genus Aphelenchoides for identification and microscopic studies. The most commonly used fixatives are formalin (Timm 1969; Szczygiel & Cid del Prado Vera 1981, Crozzoli et al. 2008, Khan et al. 2008), FAA (Wasilewska 1969; Vovlas et al. 2005, Khan et al. 2007) and TAF (Hooper 1958, Chizhov et al. 2006, Jagdale & Grewal 2006).


Sujet(s)
Fixateurs/composition chimique , Fixation tissulaire/instrumentation , Tylenchida/anatomie et histologie , Tylenchida/composition chimique , Structures anatomiques de l'animal/anatomie et histologie , Structures anatomiques de l'animal/composition chimique , Structures anatomiques de l'animal/croissance et développement , Animaux , Mensurations corporelles , Femelle , Taille d'organe , Fixation tissulaire/méthodes , Tylenchida/croissance et développement
15.
G3 (Bethesda) ; 6(8): 2285-98, 2016 08 09.
Article de Anglais | MEDLINE | ID: mdl-27233669

RÉSUMÉ

Domesticated species are often composed of distinct populations differing in the character and strength of artificial and natural selection pressures, providing a valuable model to study adaptation. In contrast to pure-breed dogs that constitute artificially maintained inbred lines, free-ranging dogs are typically free-breeding, i.e., unrestrained in mate choice. Many traits in free-breeding dogs (FBDs) may be under similar natural and sexual selection conditions to wild canids, while relaxation of sexual selection is expected in pure-breed dogs. We used a Bayesian approach with strict false-positive control criteria to identify FST-outlier SNPs between FBDs and either European or East Asian breeds, based on 167,989 autosomal SNPs. By identifying outlier SNPs located within coding genes, we found four candidate genes under diversifying selection shared by these two comparisons. Three of them are associated with the Hedgehog (HH) signaling pathway regulating vertebrate morphogenesis. A comparison between FBDs and East Asian breeds also revealed diversifying selection on the BBS6 gene, which was earlier shown to cause snout shortening and dental crowding via disrupted HH signaling. Our results suggest that relaxation of natural and sexual selection in pure-breed dogs as opposed to FBDs could have led to mild changes in regulation of the HH signaling pathway. HH inhibits adhesion and the migration of neural crest cells from the neural tube, and minor deficits of these cells during embryonic development have been proposed as the underlying cause of "domestication syndrome." This suggests that the process of breed formation involved the same genetic and developmental pathways as the process of domestication.


Sujet(s)
Sélection , Domestication , Protéines Hedgehog/génétique , Sélection génétique/génétique , Animaux , Théorème de Bayes , Chiens , Variation génétique , Génome , Étude d'association pangénomique , Génotype , Crête neurale/croissance et développement , Phénotype , Polymorphisme de nucléotide simple/génétique , Spécificité d'espèce
16.
Proc Biol Sci ; 282(1820): 20152189, 2015 12 07.
Article de Anglais | MEDLINE | ID: mdl-26631564

RÉSUMÉ

Although a large part of the global domestic dog population is free-ranging and free-breeding, knowledge of genetic diversity in these free-breeding dogs (FBDs) and their ancestry relations to pure-breed dogs is limited, and the indigenous status of FBDs in Asia is still uncertain. We analyse genome-wide SNP variability of FBDs across Eurasia, and show that they display weak genetic structure and are genetically distinct from pure-breed dogs rather than constituting an admixture of breeds. Our results suggest that modern European breeds originated locally from European FBDs. East Asian and Arctic breeds show closest affinity to East Asian FBDs, and they both represent the earliest branching lineages in the phylogeny of extant Eurasian dogs. Our biogeographic reconstruction of ancestral distributions indicates a gradual westward expansion of East Asian indigenous dogs to the Middle East and Europe through Central and West Asia, providing evidence for a major expansion that shaped the patterns of genetic differentiation in modern dogs. This expansion was probably secondary and could have led to the replacement of earlier resident populations in Western Eurasia. This could explain why earlier studies based on modern DNA suggest East Asia as the region of dog origin, while ancient DNA and archaeological data point to Western Eurasia.


Sujet(s)
Évolution biologique , Chiens/génétique , Animaux , Asie , Chiens/classification , Europe , Variation génétique , Génétique des populations , Étude d'association pangénomique , Phylogéographie , Polymorphisme de nucléotide simple
17.
J Exp Zool A Ecol Genet Physiol ; 323(10): 704-713, 2015 Dec.
Article de Anglais | MEDLINE | ID: mdl-26477614

RÉSUMÉ

The Phoridae are a family of small, hump-backed flies, dominating in post-fire areas. Some of these flies are probably able to survive a fire as an egg, larva, or pupa, and may be adapted to the fire-altered environment at the genomic level. In this study, we describe the influence of short-term temperature treatment on the expression of seven heat shock protein genes in the third-instar larvae and imagoes of a scuttle fly Megaselia scalaris-one of the cosmopolitan and polyphagous phorids. In terms of the response to temperature treatment, these genes tested against tubulin as a reference split into three classes. The first class consists of hsp22 (larvae), hsp23 (larvae), and hsp26 (both larvae and imagoes), and is upregulated at the lowest temperature (33°C). The second class consists of hsp22 (imagoes), hsp23 (imagoes), hsp40 (larvae and imagoes), and hsp70 (larvae and imagoes), and is upregulated or induced at 37°C. Expression of genes of the third class (hsp27 and hsp83-larvae and imagoes) increased after treatment at 41°C temperature. Expression of the first two classes of genes occurred at a temperature lower than the LT50 of larvae and imagoes. The fact that there is a gap between the temperature upregulating hsp genes and the temperature leading to the loss of viability suggests that not only the level of hsp gene expression but also the temperature at which gene expression increased is important in an adaptation of M. scalaris to harsh environment. J. Exp. Zool. 323A: 704-713, 2015. © 2015 Wiley Periodicals, Inc.

18.
Pol J Microbiol ; 63(1): 15-20, 2014.
Article de Anglais | MEDLINE | ID: mdl-25033657

RÉSUMÉ

The different members of the secreted aspartyl proteinase (Sap) family of the human pathogenic yeast Candida albicans are proposed to play different roles during infection and are differentially expressed at various body sites. In recent reports, expression analysis has focused on the genes SAP1-6, while the expression pattern of SAP7-10 was less well studied. We analyzed the SAP7-SAP10 expression profile of C. albicans under human serum influence that may be elucidated in the course of blood infection in humans and how this in vitro expression profile is associated with hyphal formation. The phenotypes of strains were examined under scanning electron microscopy. Quantitative RT-PCR (2-(deltadeltaC)T) was used to monitor SAP expression of C. albicans wild type cells and mutants lacking SAP9 and/or SAP10. Of the four analyzed SAP genes, only SAP7 was detectably induced in the double mutant and in the wild type strains in the model that mimics bloodstream infections. On the other hand, in the wild types (isolate 83 and CAF2-1), SAP7 was expressed 0.8- or 0.4-fold less than SAP10, respectively. Our findings suggest that Sap7 may respond to the challenge of the human blood environment. Furthermore, the results support the notion that compensatory upregulation of SAP7 and SAP8 in the deltasap9/deltasap10 mutant occurs in these conditions. SAP7-10 expression was strain-specific. Our findings point to a link between morphogenesis and expression of SAP9 in serum, where these conditions induce both hyphae and SAP9, but temporal gene expression patterns might be controlled by other factors.


Sujet(s)
Aspartic acid proteases/métabolisme , Candida albicans/métabolisme , Milieux de culture/composition chimique , Régulation de l'expression des gènes codant pour des enzymes/physiologie , Régulation de l'expression des gènes fongiques/physiologie , Mycologie/méthodes , Aspartic acid proteases/génétique , Candida albicans/génétique , Humains
19.
Reprod Fertil Dev ; 23(6): 780-7, 2011.
Article de Anglais | MEDLINE | ID: mdl-21791179

RÉSUMÉ

There is no information in the literature regarding the effect of corticotropin-releasing hormone (CRH) on genes encoding gonadotrophin-releasing hormone (GnRH) and the GnRH receptor (GnRHR) in the hypothalamus or on GnRHR gene expression in the pituitary gland in vivo. Thus, the aim of the present study was to investigate, in follicular phase ewes, the effects of prolonged, intermittent infusion of small doses of CRH or its antagonist (α-helical CRH 9-41; CRH-A) into the third cerebral ventricle on GnRH mRNA and GnRHR mRNA levels in the hypothalamo-pituitary unit and on LH secretion. Stimulation or inhibition of CRH receptors significantly decreased or increased GnRH gene expression in the hypothalamus, respectively, and led to different responses in GnRHR gene expression in discrete hypothalamic areas. For example, CRH increased GnRHR gene expression in the preoptic area, but decreased it in the hypothalamus/stalk median eminence and in the anterior pituitary gland. In addition, CRH decreased LH secretion. Blockade of CRH receptors had the opposite effect on GnRHR gene expression. The results suggest that activation of CRH receptors in the hypothalamus of follicular phase ewes can modulate the biosynthesis and release of GnRH through complex changes in the expression of GnRH and GnRHR genes in the hypothalamo-anterior pituitary unit.


Sujet(s)
Corticolibérine/pharmacologie , Phase folliculaire/métabolisme , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Hormone de libération des gonadotrophines/métabolisme , Hypothalamus/métabolisme , Adénohypophyse/métabolisme , Récepteurs à la gonadolibérine/métabolisme , Ovis/métabolisme , Analyse de variance , Animaux , Corticolibérine/agonistes , Amorces ADN/génétique , Femelle , Hormone lutéinisante/sang , Fragments peptidiques/pharmacologie , Dosage radioimmunologique , Réaction de polymérisation en chaine en temps réel
20.
J Appl Genet ; 52(2): 225-8, 2011 May.
Article de Anglais | MEDLINE | ID: mdl-21161624

RÉSUMÉ

The expression of nine functional candidates for QT abdominal fat weight and relative abdominal fat content was investigated by real-time polymerase chain reaction (PCR) in the liver, adipose tissue, colon, muscle, pituitary gland and brain of broilers. The high mobility group AT-hook 1 (HMG1A) gene was up-regulated in liver with a ratio of means of 2.90 (P ≤ 0.01) in the "fatty" group (relative abdominal fat content 3.5 ± 0.18%, abdominal fat weight 35.4 ± 6.09 g) relative to the "lean" group (relative abdominal fat content 1.9 ± 0.56%, abdominal fat weight 19.2 ± 5.06 g). Expression of this gene was highly correlated with the relative abdominal fat content (0.70, P ≤ 0.01) and abdominal fat weight (0.70, P ≤ 0.01). The peroxisome proliferator-activated receptor gamma (PPARG) gene was also up-regulated in the liver with a ratio of means of 3.34 (P ≤ 0.01) in the "fatty" group relative to the "lean" group. Correlation of its expression was significant with both the relative abdominal fat content (0.55, P ≤ 0.05) and the abdominal fat weight (0.57, P ≤ 0.01). These data suggest that the HMG1A and PPARG genes were candidate genes for abdominal fat deposition in chickens. Searching of rSNPs in regulatory regions of the HMG1A and PPARG genes could provide a tool for gene-assisted selection.


Sujet(s)
Poulets/génétique , Analyse de profil d'expression de gènes , Protéines HMGA/génétique , Foie/métabolisme , Récepteur PPAR gamma/génétique , Graisse abdominale/métabolisme , Adiposité/génétique , Animaux , Poulets/métabolisme , Spécificité d'organe
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