186 research outputs found
DNA Methyltransferase 3 (MET3) is regulated by Polycomb group complex during Arabidopsis endosperm development
Complex epigenetic changes occur during plant reproduction. These regulations ensure the proper transmission of epigenetic information as well as allowing for zygotic totipotency. In Arabidopsis, the main DNA methyltransferase is called MET1 and is responsible for methylating cytosine in the CG context. The Arabidopsis genome encodes for three additional reproduction-specific homologs of MET1, namely MET2a, MET2b and MET3. In this paper, we show that the DNA methyltransferase MET3 is expressed in the seed endosperm and its expression is later restricted to the chalazal endosperm. MET3 is biallelically expressed in the endosperm but displays a paternal expression bias. We found that MET3 expression is regulated by the Polycomb complex proteins FIE and MSI1. Seed development is not impaired in met3 mutant, and we could not observe significant transcriptional changes in met3 mutant. MET3 might regulates gene expression in a Polycomb mutant background suggesting a further complexification of the interplay between H3K27me3 and DNA methylation in the seed endosperm
Methylome Response to Proteasome Inhibition by Pseudomonas syringae Virulence Factor Syringolin A
DNA methylation is an important epigenetic mark required for proper gene expression and silencing of transposable elements. DNA methylation patterns can be modified by environmental factors such as pathogen infection, in which modification of DNA methylation can be associated with plant resistance. To counter the plant defense pathways, pathogens produce effector molecules, several of which act as proteasome inhibitors. Here, we investigated the effect of proteasome inhibition by the bacterial virulence factor syringolin A (SylA) on genome-wide DNA methylation. We show that SylA treatment results in an increase of DNA methylation at centromeric and pericentromeric regions of Arabidopsis chromosomes. We identify several CHH differentially methylated regions (DMRs) that are enriched in the proximity of transcriptional start sites. SylA treatment does not result in significant changes in small RNA composition. However, significant changes in genome transcriptional activity can be observed, including a strong upregulation of resistance genes that are located on chromosomal arms. We hypothesize that DNA methylation changes could be linked to the upregulation of some atypical members of the de novo DNA methylation pathway, namely AGO3, AGO9, and DRM1. Our data suggests that modification of genome-wide DNA methylation resulting from an inhibition of the proteasome by bacterial effectors could be part of an epi-genomic arms race against pathogens. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license
Functional characterization of Arabidopsis ARGONAUTE 3 in reproductive tissues
Arabidopsis encodes ten ARGONAUTE (AGO) effectors of RNA silencing, canonically loaded with either 21â22 nucleotide (nt) long small RNAs (sRNA) to mediate postâtranscriptionalâgeneâsilencing (PTGS) or 24nt sRNAs to promote RNAâdirectedâDNAâmethylation. Using fullâlocus constructs, we characterized the expression, biochemical properties, and possible modes of action of AGO3. Although AGO3 arose from a recent duplication at the AGO2 locus, their expression patterns differ drastically, with AGO2 being expressed in both male and female gametes whereas AGO3 accumulates in aerial vascular terminations and specifically in chalazal seed integuments. Accordingly, AGO3 downâregulation alters gene expression in siliques. Similar to AGO2, AGO3 binds sRNAs with a strong 5ââadenosine bias, but unlike Arabidopsis AGO2, it binds most efficiently 24nt sRNAs. AGO3 immunoprecipitation experiments in siliques revealed that these sRNAs mostly correspond to genes and intergenic regions in a manner reflecting their respective accumulation from their lociâofâorigin. AGO3 localizes to the cytoplasm and coâfractionates with polysomes to possibly mediate PTGS via translation inhibition
Ătude sur la prĂ©servation des abeilles sauvages du Kauwberg (Uccle) dans une perspective de dĂ©veloppement agricole et ludo-sportif du site
Principaux constats
· 95 espĂšces dâabeilles sauvages ainsi que 62 espĂšces de syrphes ont Ă©tĂ© recensĂ©es au
sein du site du Kauwberg entre les années 2020 et 2021.
· Sur lâensemble de la richesse dâabeilles sauvages, 15 espĂšces sont menacĂ©es (statut de liste
rouge nationale) au sein du Kauwberg : une espĂšce en danger dâextinction, deux en situation
vulnérables, dix en statuts presque menacées et deux dont les données sont déficientes.
· Sur lâensemble de la richesse dâabeilles sauvages, 15 espĂšces sont oligolectiques et 80
polylectiques
· Nâayant pas de liste rouge pour les espĂšces de syrphes de Belgique, 10 espĂšces enregistrĂ©es
sont à considérer comme rares à trÚs rares, ce qui démontre une nouvelle fois que le site du
Kauwberg accueille riche biodiversitĂ© de pollinisateurs ; aucune nâest toutefois considĂ©rĂ©e en
danger Ă lâĂ©chelle europĂ©enne.
· Les milieux ouverts et les potagers se rĂ©vĂšlent ĂȘtre les plus riches et abondants en abeilles
sauvages.
· Au sein des habitats ouverts et potagers, une dominance se dessine vis-Ă -vis dâApis mellifera,
omniprésente dans cette zone naturelle protégée.
Recommandations de gestion
· Constituer des bandes fleuries adaptĂ©es Ă ces espĂšces dâabeilles oligolectiques et/ou
menacĂ©es dâextinction.
· Maintenir et Ă©difier de zones de nidification dâespĂšces oligolectiques et/ou menacĂ©es
dâextinction : bois mort, zones dĂ©pourvues de vĂ©gĂ©tation orientĂ©es plein Sud (sabliĂšre, lisiĂšre
de forĂȘtâŠ)
· Maintenir une activité maraßchÚre dans le site, importante par la diversité floristique que ces
micro-habitats proposent.
· Maintenir les buttes artificiellement construites pour les activités de dirtbike, utiles pour les nids
des insectes/abeilles terricoles.
· RĂ©duire la pression exercĂ©e par lâapiculture en rĂ©duisant voire supprimant les ruches prĂ©sentes
directement sur le site.
· Ouvrir le versant Ouest de la sabliĂšre pour augmenter lâopportunitĂ© de nidification des abeilles
terricoles avec une mise en défens du lieu de Mars à Octobre de chaque année pour aider à la
conservation et régénération de ces bourgades
Constitution et passé
Issu dâune journĂ©e dâĂ©tudes qui sâest tenue Ă Aix-Marseille UniversitĂ© en 2020, le prĂ©sent ouvrage propose des rĂ©flexions sur les rapports que la Constitution entretient avec le passĂ©, sur la façon dont elle le reprĂ©sente, lâapprĂ©hende, le traite voire lâutilise. Ce thĂšme, abordĂ© par les jeunes chercheurs de lâInstitut Louis Favoreu sous le parrainage de chercheurs expĂ©rimentĂ©s, trouve, dans lâactualitĂ©, des rĂ©sonances importantes avec, par exemple, la multiplication des lois mĂ©morielles et des devoirs de mĂ©moire, les dĂ©bats soulevĂ©s par une «⯠cancel culture âŻÂ» constitutionnelle ou encore la constitutionnalisation de «⯠vĂ©ritĂ©s âŻÂ» historiques. Les diffĂ©rentes contributions analysent, dans une perspective historique et comparĂ©e, la façon dont la Constitution/les Constitutions se saisissent du passĂ© : Ă cet Ă©gard, elles soulignent la diversitĂ© des maniĂšres de reprĂ©senter le passĂ© voire de se lâapproprier et interrogent la spĂ©cificitĂ© du discours constitutionnel sur le passĂ©. Elles analysent Ă©galement la façon dont la/les Constitutions utilisent le passĂ©, comment ce dernier intervient au soutien de la construction du rĂ©cit constitutionnel et comment il peut ĂȘtre mobilisĂ© par les diffĂ©rents acteurs constitutionnels, notamment le juge
Monitoring Greenland ice sheet buoyancy-driven calving discharge using glacial earthquakes
Since the 2000s, Greenland ice sheet mass loss has been accelerating, followed by increasing numbers of glacial earthquakes (GEs) at near-grounded glaciers. GEs are caused by calving of km-scale icebergs which capsize against the terminus. Seismic record inversion allows a reconstruction of the history of GE sources which captures capsize dynamics through iceberg-to-terminus contact. When compared with a catalog of contact forces from an iceberg capsize model, seismic force history accurately computes calving volumes while the earthquake magnitude fails to uniquely characterize iceberg size, giving errors up to 1 km Âł . Calving determined from GEs recorded ateight glaciers in 1993â2013 accounts for up to 21% of the associated discharge and 6% of the Greenland mass loss. The proportion of discharge attributed to capsizing calving may be underestimated by at least 10% as numerous events could not be identified by standard seismic detections (Olsen and Nettles, 2018). While calving production tends to stabilize in East Greenland, Western glaciers have released more and larger icebergs since 2010 and have become major contributors to Greenland dynamic discharge. Production of GEs and calving behavior are controlled by glacier geometry with bigger icebergs being produced when the terminus advances in deepening water. We illustrate how GEs can help in partitioning and monitoring Greenland mass loss and characterizing capsize dynamics
Volume 98 Issue 5, pp. 899-1054
ECOLOGY-EPIDEMIOLOGY-BEHAVIOR
Increased Surfacing Behavior in Longnose Killifish Infected by Brain-Encysting Trematode. B. L. FREDENSBORG and A. N. LONGORIA - 899
Spatial Structure of Helminth Communities in the Golden Grey Mullet, Liza aurata (Actinopterygii: Mugilidae), From the Western Mediterranean. RAUL MIGUEZ-LOZANO, TRINIDAD V. PARDO-CARRANZA, ISABEL BLASCO-COSTA, and JUAN ANTONIO BALBUENA - 904
Hepatozoon Infection Prevalence in Four Snake Genera: Influence of Diet, Prey Parasitemia Levels, or Parasite Type? BEATRIZ TOME, JOAD P. M. C. MAIA, and D. JAMES HARRIS - 913
ECTOPARASITOLOGY
Molecular Identification and Description of the Female of Nothoaspis reddelli (Ixodida: Argasidae) From a Cave in Southeastern Mexico. CARMEN GUZMAN-CORNEJO, RICARDO PAREDES-LEON, MARCELO B. LABRUNA, SANTIAGO NAVA, and JOSE M. VENZAL - 918
Prevalence of Hemoproteus iwa in Galapagos Great Frigatebirds (Fregata minor) and Their Obligate Fly Ectoparasite (01- Jersia spiniJera). IRIS I. LEVIN and PATRICIA G. PARKER - 924
Variable Microsatellite Loci for Population Genetic Analysis of Old World Monkey Lice (Pedicinus sp.). KATLYN SCHOLL, JULIE M. ALLEN, FABIAN H. LEENDERTZ, COLIN A. CHAPMAN, and DAVID L. REED - 930
FUNCTIONAL MORPHOLOGY
Ultrastructural Study of Vitellogenesis of Aphallus tubarium (Rudolphi, 1819) Poche, 1926 (Digenea: Cryptogonimidae), an Intestinal Parasite of Dentex dentex (Pisces: Teleostei). SAMUEL GREANI, YANN QUILICHINI, JOSEPHINE FOATA, and BERNARD MARCHAND - 938
IMMUNOLOGY
Seroprevalence of Toxoplasma gondii Infection in Domestic Horses in Durango State, Mexico. C. ALVARADO-ESQUIVEL, S. RODRIGUEZ-PENA, I. VILLENA, and J. P. DUBEY - 944
INVERTEBRATE-PARASITE RELATIONSHIPS
Excystation Signals Do Not Isolate Gregarine Gene Pools: Experimental Excystation of Blabericola migrator Among 11 Species of Cockroaches. SHELBY M. STEELE, DEBRA T. CLOPTON, and RICHARD E. CLOPTON - 946
LIFE CYCLES-SURVEY
A New Sarcocystis Species (Apicomplexa: Sarcocystidae) From the Rock Gecko Bunopus tuberculatus in Saudi Arabi. A. S. ABDEL-BAKI, H. M. ABDEL-HALEEM, and S. AL-QURAISHY - 951
A Retrospective Study of Abattoir Condemnation Due to Parasitic Infections: Economic Importance in Ahwaz, Southwestern Iran. HASSAN BORJI, MOHAMMAD AZIZZADEH, and MEHRAB KAMELLI - 954
Prevalence of Eimeria Infection in Yaks on the Qinghai-Tibet Plateau of China. HUI DONG, CHUNHUA LI, QIPING ZHAO, JING LI, HONGYU HAN, LIANLIAN JIANG, SHUNHAI ZHU, TING LI, CHUNLIN KONG, BING HUANG, and JINZHONG CAI - 958
Prevalence of Coccidial Infection in Dairy Cattle in Shanghai, China. HUI DONG, QIPING ZHAO, HONGYU HAN, LIANLIAN JIANG, SHUNHAI ZHU, TING LI, CHUNLIN KONG, and BING HUANG - 963
Genetic Sequence Data Identifies the Cercaria of Drepanocephalus spathans (Digenea: Echinostomatidae), a Parasite of the Double-Crested Cormorant (Phalacrocorax auritus), with Notes on Its Pathology in Juvenile Channel Catfish (Ictalurus punctatus). MATT J. GRIFFIN, LESTER H. KHOO, SYLVIE M. QUINIOU, MARY M. O\u27HEAR, LINDA M. POTE, TERRENCE E. GREENWAY, and DAVID J. WISE - 967
SYSTEMATICS-PHYLOGENETICS
A New Species of Megalobatrachonema (Nematoda: Kathlaniidae) in Fojia bumui (Squamata: Scincidae) From Papua New Guinea. CHARLES R. BURSEY, STEPHEN R. GOLDBERG, and FRED KRAUS - 973
Two New Species of Schizorchis (Cestoda: Anoplocephalidae) From Leporids (Lagomorpha: Leporidae) in China. KUIZHENG CAI, JIALIN BAI, and SHIEN CHEN - 977
The Genus Guerrerostrongylus (Nematoda: Heligmonellidae) in Cricetid Rodents From the Atlantic Rain Forest of Misiones, Argentina: Emended Description of Guerrerostrongylus zetta (Travassos, 1937) and Description of a New Species. MARIA CELINA DIGIANI, JULIANA NOTARNICOLA, and GRACIELA T. NAVONE - 985
A New Microphallid (Digenea) Species From Lontra provocax (Mammalia: Mustelidae) From Freshwater Environments of Northwestern Patagonia (Argentina). VERONICA R. FLORES, NORMA L. BRUGNI, and CARLA M. POZZI - 992
Description of Riouxgolvania kapapkamui sp. n. (Nematoda: Muspiceoidea: Muspiceidae), a Peculiar Intradermal Parasite of Bats in Hokkaido, Japan. HIDEO HASEGAWA, MASAHIKO SATO, KISHIO MAEDA, and YOSHIKO MURAYAMA - 995
A New Species of Choleoeimeria (Apicomplexa: Eimeriidae) From Meller\u27s Chameleon, Trioceros melleri (Sauria: Chamaeleonidae). CHRIS T. McALLISTER - 1001
A New Species of Eimeria (Apicomplexa: Eimeriidae) From the Northern Myotis, Myotis septentrionalis (Chiroptera: Vespertilionidae), in Oklahoma. CHRIS T. McALLISTER, R. SCOTT SEVILLE, and ZACHARY P. ROEHRS - 1003
A New Spirurid (Nematoda) Parasite From Mormoopid Bats in Mexico. JORGE LUIS PERALTA-RODRIGUEZ, JUAN MANUEL CASPETA-MANDUJANO, and JOSE ANTONIO GUERRERO - 1006
THERAPEUTICS-DIAGNOSTICS
Resistance of Rhipicephalus microplus to Amitraz and Cypermethrin in Tropical Cattle Farms in Veracruz, Mexico. AGUSTIN FERNANDEZ-SALAS, ROGER IVAN RODRIGUEZ-VIVAS, and MIGUEL ANGEL ALONSO-DIAZ - 1010
RESEARCH NOTES
Seroprevalence Study on Theileria equi and Babesia caballi Antibodies in Horses From Central Province of Saudi Arabia. A. D. ALANAZI, M. S. ALYOUSIF, and M. M. HASSIEB - 1015
Influence of Rangelia vitalii (Apicomplexa: Piroplasmorida) on Copper, Iron and Zinc Bloodstream Levels in Experimentally Infected Dogs, ALEKSANDRO S, DA SILVA, RAQUELI T. FRANC;:A, MARCIO M. COSTA, CARLOS B. V. PAIM, FRANCINE C. PAIM, CLARISSA M. M. SANTOS, ERICO M. M. FLORES, TIAGO L. EILERS, CINTHIA M. MAZZANTI, SILVIA G. MONTEIRO, CARLOS H. DO AMARAL, and SONIA T. A. LOPES - 1018
Plagiorchis elegans (Trematoda) Induces Immune Response in an Incompatible Snail Host Biomphalaria glabrata (Pulmonata: Planorbidae). S. P. DAOUST, M. E. RAU, and J. D. McLAUGHLIN - 1021
Prevalence and Intensity of Fish-Borne Zoonotic Trematodes in Cultured Freshwater Fish From Rural and Urban Areas of Northern Vietnam. NGUYEN VAN DE, THANH HOA LE, and K. D. MURRELL - 1023
Details of the Paranephridial System of a Species of Prohyptiasmus (Cyclocoelidae: Hyptiasminae) From an American Coot, Fulica americana (Rallidae) in Oklahoma. NORMAN O. DRONEN, F. AGUSTIN JIMENEZ, and SCOTT L. GARDNER - 1026
Surface Ultrastructure of the Eggs of Malacopsylla grossiventris and Phthiropsylla agenoris (Siphonaptera: Malacopsyllidae). M. C. EZQUIAGA and M. LARES CHI - 1029
Prevalence of Ancylostoma braziliense in Cats in Three Northern Counties of Florida, United States. JANICE L. LIOTTA, KHUANCHAI N. KOOMPAPONG, JOSEPH P. YAROS, JOSEPH PRULLAGE, and DWIGHT D. BOWMAN - 1032
Obtaining an Isolate of Ancylostoma braziliense From Dogs Without the Need for Necropsy. JANICE L. LIOTTA, ALICE C. Y. LEE, SARP AKSEL, IBRAHIM ALKHALIFE, ALEJANDRO CRUZ-REYES, HEEJEONG YOUN, STEPHEN E. BIENHOFF, and DWIGHT D. BOWMAN - 1034
Obtaining an Isolate of Ancylostoma braziliense From Cats Without the Need for Necropsy. JANICE L. LIOTTA, ALICE C. Y. LEE, KHUANCHAI N. KOOMPAPONG, JOSEPH P. YAROS, JOSEPH PRULLAGE, MICHAEL A. ULRICH, and DWIGHT D. BOWMAN - 1037
Prevalence of Ancylostoma braziliense in Dogs From Alachua and Marion Counties, Florida, United States. JANICE L. LIOTTA, HEEJEONG YOUN, SARP AKSEL, STEPHEN E. BIENHOFF, and DWIGHT D. BOWMAN - 1039
Morphological Differentiation of Eggs of Ancylostoma caninum, Ancylostoma tubaeforme, and Ancylostoma braziliense From Dogs and Cats in the United States. ARACELI LUCIO-FORSTER, JANICE L. LIOTTA, JOSEPH P. YAROS, KAITLYN R. BRIGGS, HUSSNI O. MOHAMMED, and DWIGHT D. BOWMAN - 1041
Molecular and Immunological Characterization of a Novel 32-kDa Secreted Protein of Babesia microti. HIDEO OOKA, MOHAMAD A. TERKAWI, SHINUO CAO, GABRIEL ABOGE, YO UN-KYOUNG GOO, YUZI LUO, YAN LI, YOSHIFUMI NISHIKAWA, IKUO IGARASHI, and XUENAN XUAN - 1045
DNA Barcoding of Schistosome Cercariae Reveals a Novel Sub-Lineage within Schistosoma rodhaini From Ngamba Island Chimpanzee Sanctuary, Lake Victoria. C. J. STANDLEY and J. R. STOTHARD - 1049
Host Susceptibility Is Altered by Light Intensity After Exposure to Parasites. MICHELLE L. STEINAUER and KAITLIN M. BONNER - 1052
ANNOUNCEMENT:
Change in Editorship - 903
ERRATUM - 91
EMDR Effects on Pursuit Eye Movements
This study aimed to objectivize the quality of smooth pursuit eye movements in a standard laboratory task before and after an Eye Movement Desensitization and Reprocessing (EMDR) session run on seven healthy volunteers. EMDR was applied on autobiographic worries causing moderate distress. The EMDR session was complete in 5 out of the 7 cases; distress measured by SUDS (Subjective Units of Discomfort Scale) decreased to a near zero value. Smooth pursuit eye movements were recorded by an Eyelink II video system before and after EMDR. For the five complete sessions, pursuit eye movement improved after their EMDR session. Notably, the number of saccade intrusionsâcatch-up saccades (CUS)âdecreased and, reciprocally, there was an increase in the smooth components of the pursuit. Such an increase in the smoothness of the pursuit presumably reflects an improvement in the use of visual attention needed to follow the target accurately. Perhaps EMDR reduces distress thereby activating a cholinergic effect known to improve ocular pursuit
Severe Asthma Standard-of-Care Background Medication Reduction With Benralizumab: ANDHI in Practice Substudy
Background: The phase IIIb, randomized, parallel-group, placebo-controlled ANDHI double-blind (DB) study extended understanding of the efficacy of benralizumab for patients with severe eosinophilic asthma. Patients from ANDHI DB could join the 56-week ANDHI in Practice (IP) single-arm, open-label extension substudy. Objective: Assess potential for standard-of-care background medication reductions while maintaining asthma control with benralizumab. Methods: Following ANDHI DB completion, eligible adults were enrolled in ANDHI IP. After an 8-week run-in with benralizumab, there were 5 visits to potentially reduce background asthma medications for patients achieving and maintaining protocol-defined asthma control with benralizumab. Main outcome measures for non-oral corticosteroid (OCS)-dependent patients were the proportions with at least 1 background medication reduction (ie, lower inhaled corticosteroid dose, background medication discontinuation) and the number of adapted Global Initiative for Asthma (GINA) step reductions at end of treatment (EOT). Main outcomes for OCS-dependent patients were reductions in daily OCS dosage and proportion achieving OCS dosage of 5 mg or lower at EOT. Results: For non-OCS-dependent patients, 53.3% (n = 208 of 390) achieved at least 1 background medication reduction, increasing to 72.6% (n = 130 of 179) for patients who maintained protocol-defined asthma control at EOT. A total of 41.9% (n = 163 of 389) achieved at least 1 adapted GINA step reduction, increasing to 61.8% (n = 110 of 178) for patients with protocol-defined EOT asthma control. At ANDHI IP baseline, OCS dosages were 5 mg or lower for 40.4% (n = 40 of 99) of OCS-dependent patients. Of OCS-dependent patients, 50.5% (n = 50 of 99) eliminated OCS and 74.7% (n = 74 of 99) achieved dosages of 5 mg or lower at EOT. Conclusions: These findings demonstrate benralizumab's ability to improve asthma control, thereby allowing background medication reduction
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