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 21‐22 nucleotide (nt) long small RNAs (sRNA) to mediate post‐transcriptional‐gene‐silencing (PTGS) or 24nt sRNAs to promote RNA‐directed‐DNA‐methylation. Using full‐locus 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 down‐regulation alters gene expression in siliques. Similar to AGO2, AGO3 binds sRNAs with a strong 5’‐adenosine 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 loci‐of‐origin. AGO3 localizes to the cytoplasm and co‐fractionates with polysomes to possibly mediate PTGS via translation inhibition

Constitution et passé

Issu d’une journée d’études qui s’est tenue à Aix-Marseille Université en 2020, le présent ouvrage propose des réflexions sur les rapports que la Constitution entretient avec le passé, sur la façon dont elle le représente, l’appréhende, le traite voire l’utilise. Ce thème, abordé par les jeunes chercheurs de l’Institut Louis Favoreu sous le parrainage de chercheurs expérimentés, trouve, dans l’actualité, des résonances importantes avec, par exemple, la multiplication des lois mémorielles et des devoirs de mémoire, les débats soulevés par une «  cancel culture  » constitutionnelle ou encore la constitutionnalisation de «  vérités  » historiques. Les différentes contributions analysent, dans une perspective historique et comparée, la façon dont la Constitution/les Constitutions se saisissent du passé : à cet égard, elles soulignent la diversité des manières de représenter le passé voire de se l’approprier et interrogent la spécificité du discours constitutionnel sur le passé. Elles analysent également la façon dont la/les Constitutions utilisent le passé, comment ce dernier intervient au soutien de la construction du récit constitutionnel et comment il peut être mobilisé par les différents 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 ³ . Calving determined from GEs recorded ateight glaciers in 1993–2013 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

Thermally Switchable Nanogate Based on Polymer Phase Transition

Mimicking and extending the gating properties of biological pores is of paramount interest for the fabrication of membranes that could be used in filtration or drug processing. Here, we build a selective and switchable nanopore for macromolecular cargo transport. Our approach exploits polymer graftings within artificial nanopores to control the translocation of biomolecules. To measure transport at the scale of individual biomolecules, we use fluorescence microscopy with a zero-mode waveguide set up. We show that grafting polymers that exhibit a lower critical solution temperature creates a toggle switch between an open and closed state of the nanopore depending on the temperature. We demonstrate tight control over the transport of DNA and viral capsids with a sharp transition (∼1 °C) and present a simple physical model that predicts key features of this transition. Our approach provides the potential for controllable and responsive nanopores in a range of applications

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 intrusions—catch-up saccades (CUS)—decreased 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