@article {721, title = {Molecular phylogeny of Malenchus and Filenchus (Nematoda: Tylenchidae)}, journal = {Zoologica ScriptaZoologica Scripta}, volume = {in press}, year = {2017}, author = {Qing, X. and Decraemer, W. and Claeys, M. and Bert, W.} } @article {724, title = {Ultrastructure of sperm development in the genus Ditylenchus (Nematoda: Anguinidae)}, journal = {NematologyNematology}, volume = {17}, year = {2015}, pages = {313-324}, author = {Slos, D. and Ensafi, P. and Claeys, M. and Yushin, V.V. and Decraemer, W. and Bert, W.} } @article {730, title = {A hotspot of amoebae diversity: 8 new naked amoebae associated with the planktonic bloom-forming cyanobacterium Microcystis }, journal = {Acta ProtozoologicaActa Protozoologica}, volume = {51}, number = {2}, year = {2015}, pages = {2016}, author = {Van Wichelen, J. and D{\textquoteright}hondt, S. and Claeys, M. and Vyverman, W. and Berney, C. and Bass, D. and Vanormeling, P.} } @article {733, title = {Ultrastructural immunogold localization of major sperm protein (MSP) in spermatogenic cells of the nematode Acrobeles complexus (Nematoda, Rhabditida)}, journal = {Micron 89, 43-55Micron 89, 43-55}, number = {89}, year = {2016}, pages = { 43-55}, author = {Yushin, V.V. and Claeys, M. and Bert, W.} } @article {411, title = {High-pressure freezing and freeze-substitution fixation reveal the ultrastructure of immature and mature spermatozoa of the plant-parasitic nematode Trichodorus similis (Nematoda; Triplonchida; Trichodoridae)}, journal = {Micron}, volume = {77}, year = {2015}, pages = {25-31}, author = {Lak, B. and Yushin, V. V. and Slos, D. and Claeys, M. and Decraemer, W. and Bert, W.} } @article {413, title = {Transmission electron microscopy sample preparation protocols for ultrastructural study of cysts of free-living protozoa}, journal = {BiotechniquesBiotechniques}, volume = {58}, year = {2015}, pages = {181-188}, author = {Lambrecht, E. and Bar{\'e}, J. and Claeys, M. and Chavatte, N. and Bert, W. and Sabbe, K. and Houf, K.} } @article {306, title = {ULTRASTRUCTURE OF SPERM CELLS IN THE FEMALE GONODUCT OF XIPHINEMA}, journal = {Tissue \& CellTissue \& Cell}, volume = {23}, number = {6}, year = {1991}, note = {Vandevelde, mc coomans, a vanranst, l kruger, jcd claeys, m}, pages = {881-891}, abstract = {The ultrastructure of the sperm cells in the female gonoduct of the nematodes Xiphinema theresiae and X. pinoides is described. The nucleus of the sperm cells is composed of several electron-dense clumps of chromatin that is not surrounded by a nuclear envelope. A layer of mitochondria, in which the mitochondrial cristae are only rarely visible, lies around the nuclear material. In the surrounding cytoplasm packets of electron-dense fibres are abundant. The sperm in the uterus have the following surface differentiations: highly intertwined protrusions between adjacent sperm cells, protrusions coinciding with the plication of the inner uterine wall and a slightly undulated surface towards the uterine lumen. It is argued that in the uterus, the sperm cells actively move in proximal direction by a mechanism resembling pseudopodial movement, in which the packets of fibres are involved. In the oviduct, the sperm cells loose their surface protrusions and the packets of fibres gradually become less abundant. Since the oviduct has no pre-formed lumen, the sperm cells appear to wedge their way along by forcing oviduct cells apart.}, isbn = {0040-8166}, author = {VandeVelde, M. C. and Coomans, A. and Vanranst, L. and Kruger, J. C. D. and Claeys, M.} } @article {260, title = {Effect of nematicidal Bacillus thuringiensis strains on free-living nematodes .2. Ultrastructural analysis of the intoxication process in Caenorhabditis elegans}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {19}, number = {5}, year = {1996}, note = {Borgonie, G Claeys, M Leyns, F Arnaut, G DeWaele, D Coomans, A}, pages = {407-414}, abstract = {Transmission electron microscopy is used to describe the intoxication in Caenorhabditis elegans, feeding on toxic spore/crystals of Bacillus thuringiensis. The toxin acts directly against the intestine, first by affecting the anteriormost ring of four intestinal cells. Over a period of 12 hours, these cells lose much of their volume, the microvilli regress slowly, several cell organelles undergo dramatic change and are ultimately destroyed. No rupture of the apical intestinal cell membrane is observed. Non-intestinal tissues seem unaffected. This study indicates considerable ultrastructural differences in the mode of action between the nematicidal toxin and the insecticidal crystal toxins from B. thuringiensis.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and Leyns, F. and Arnaut, G. and DeWaele, D. and Coomans, A.} } @article {261, title = {Effect of a nematicidal Bacillus thuringiensis strain on free-living nematodes .3. Characterization of the intoxication process}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {19}, number = {6}, year = {1996}, note = {Borgonie, G Claeys, M Leyns, F Arnaut, G DeWaele, D Coomans, A}, pages = {523-528}, abstract = {The toxicity of Bacillus thuringiensis is temperature sensitive. Incubation of Caenorhabditis elegans with nematicidal B. thuringiensis strains at 16, 20, and 25 degrees C shows that toxicity decreases as temperature declines. At 16 degrees C, toxicity is completely lost, while it is maximal at 25 degrees C. Toxicity is pH sensitive and is significantly reduced when nematodes are incubated with the weak bases NH4Cl, chloroquine, acridine orange, methyl red, and neutral red. Based on these results, we proposed the hypothesis that the nematicidal factor is effectively internalized into the intestinal cells, a sharp deviation from the insecticidal B. thuringiensis toxins acting at the level of the brush border membrane. Although the absence of purified toxin prevents a more definitive elucidation of the mode of action, the results of this third and final part of this series of publications convincingly indicate that nematicidal B. thuringiensis do not hold the same promise as a biological control agent as the insecticidal B. thuringiensis strains.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and Leyns, F. and Arnaut, G. and DeWaele, D. and Coomans, A.} } @article {262, title = {Effect of nematicidal Bacillus thuringiensis strains on free-living nematodes .1. Light microscopic observations, species and biological stage specificity and identification of resistant mutants of Caenorhabditis elegans}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {19}, number = {4}, year = {1996}, note = {Borgonie, G Claeys, M Leyns, F Arnaut, G DeWaele, D Coomans, A}, pages = {391-398}, abstract = {Light-microscopic observations of the toxic action of Bacillus thuringiensis spore/crystals reveals that, in Caenorhabditis elegans, the intestine is destroyed in two stages over a period of 24 h. The anterior ring of four cells is the first and foremost target. Observations indicate that the intestine is the only tissue being destroyed. Screening of fourteen additional rhabditid nematode species against three nematicidal B. thuringiensis strains active against C. elegans, resulted in only one additional sensitive nematode species, and indicates a high species specificity of the nematicidal factor. However, in contrast to insect-specific B. thuringiensis toxins, the nematicidal toxin exhibits low developmental stage specificity against C. elegans; all developmental stages, including adult nematodes are sensitive. Moreover, sensitivity increases as development proceeds. Using ethyl methyl sulfonate induced mutagenesis two mutants of C. elegans have been recovered, exhibiting reduced sensitivity of up to 50 \% against one of the nematicidal strains. Moreover, one of the mutants exhibited cross-resistance to a second nematicidal B. thuringiensis strain against which it was not screened. Preliminary data indicate that the reduced sensitivity in the mutants is not due to reduced pharyngeal pumping activity.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and Leyns, F. and Arnaut, G. and DeWaele, D. and Coomans, A.} } @article {276, title = {PRESENCE OF PERITROPHIC-LIKE MEMBRANES IN THE INTESTINE OF 3 BACTERIOPHAGOUS NEMATODES (NEMATODA, RHABDITIDA)}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {18}, number = {3}, year = {1995}, note = {Borgonie, g claeys, m vanfleteren, j dewaele, d coomans, a}, pages = {227-233}, abstract = {Ultrastructural analysis shows the presence of membranes originating at the top of the intestinal microvilli, along the entire length of the intestine in the three rhabditid nematodes Caenorhabditis elegans, Panagrolaimus superbus and Acrobeloides maximus. The membranes allow the passage of fluorescein isothiocyanate, methyl red, neutral red and acridine orange, but allow only sparse passage of ferritin molecules. Upon the introduction of a sublethal dose of sodium azide, the intestinal lumen displays an increased secretion of membrane layers. Whole mount staining of the nematodes with the Solanum tuberosum and Triticum vulgare lectins, known to bind with high affinity to chitin, shows only specific binding of Solanum tuberosum lectin to the brush border in all developmental stages of C. elegans, P. superbus and A. maximus. The results reveal the presence of membranes in the intestine of three species of one of the most ancient metazoan phyla, exhibiting morphological and functional characteristics reminiscent of peritrophic membranes in insects.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and Vanfleteren, J. and DeWaele, D. and Coomans, A.} } @article {277, title = {IN-VIVO AND IN-VITRO CHARACTERIZATION OF THE INTESTINE OF 15 BACTERIOPHAGOUS NEMATODES (NEMATODA, RHABDITIDA)}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {18}, number = {2}, year = {1995}, note = {Borgonie, g claeys, m dewaele, d coomans, a}, pages = {115-122}, abstract = {The intestine of the fifteen free-living Rhabditida belonging to three different families was studied using three different approaches : i) using three different axenic media, cultivation of all fifteen nematode species was attempted; ii) in vivo analyses were performed by using two vital stains and one fluorescent dye and by comparing staining patterns; iii) in vitro analyses was done using the intestinal markers acid phosphatase, esterase and the lectin of Ricinus communis II. Although the nematodes can be cultured monoxenically on the same bacterium, Escherichia coli, attempts to culture the fifteen nematode species on the same axenic medium failed. Distinct differences are observed between different areas along the intestinal tract by in vivo study using stains. Similar observations were made in vitro using the intestinal marker acid phosphatase and the binding pattern of Ricinus communis II. This was less evident using esterase as a marker, since considerable non-intestinal tissue staining was evident. The data obtained indicate considerable biochemical differences in the intestinal cells between the nematode species, even if the nematode species belong to the same family.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and DeWaele, D. and Coomans, A.} } @article {278, title = {ULTRASTRUCTURE OF THE INTESTINE OF THE BACTERIOPHAGOUS NEMATODES CAENORHABDITIS-ELEGANS, PANAGROLAIMUS SUPERBUS AND ACROBELOIDES MAXIMUS (NEMATODA, RHABDITIDA)}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {18}, number = {2}, year = {1995}, note = {Borgonie, g claeys, m dewaele, d coomans, a}, pages = {123-133}, abstract = {The intestine of the three free-living rhabditid nematodes Caenorhabditis elegans, Panagrolaimus superbus and Acrobeloides maximus was studied using transmission electron microscopy of sections made at three locations along the intestine. Between the three nematode species, ultrastructural differences in cellular components are minor. However, two cell types present in all three nematode species are positioned differently along the intestinal tract. Furthermore, two different types of secretions into the intestinal lumen were identified, one only at the anterior intestine, the second present along the entire length of the intestinal lumen. F-actin staining of fifteen whole-mount nematodes revealed the presence of a well developed, cross-shaped intestinal muscle, only present in Cephalobid species.}, isbn = {1164-5571}, author = {Borgonie, G. and Claeys, M. and DeWaele, D. and Coomans, A.} } @article {219, title = {Transovarial transmission of symbionts in Xiphinema brevicollum (Nematoda : Longidoridae)}, journal = {NematologyNematology}, volume = {2}, year = {2000}, note = {Coomans, A Vandekerckhove, TTM Claeys, MPart 4}, pages = {443-449}, abstract = {Transovarial transmission of bacterial symbionts in Xiphinema brevicollum was examined by means of electron microscopical- and fluorescence microscopical observations of intra-uterine and freshly laid non-embryonated eggs, as well as of embryonated eggs. The symbionts are mainly aggregated near one of the egg poles and this is observed in non-embryonated as well as in embryonated eggs. The bacteria are present in intestinal cells of first stage juveniles that are still enclosed by the egg-shell. In subsequent juvenile developmental stages their number increases and the intestinal cells are filled with the symbionts. Bacteria were not present in the genital primordium. It is hypothesised that the aggregated symbionts at one of the egg poles become enclosed in the E founder cell during embryogenesis and subsequently are distributed to the endodermal daughter cells. The bacteria become enclosed in the ovarial wall through an unknown mechanism only during the later stages of gonad development.}, isbn = {1388-5545}, author = {Coomans, A. and Vandekerckhove, T. T. M. and Claeys, M.} } @article {236, title = {Structure of the female reproductive system of Xiphinema americanum (Nematoda : Longidoridae)}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {21}, number = {5}, year = {1998}, note = {Coomans, A Claeys, M}, month = {Sep-Oct}, pages = {569-580}, abstract = {The female reproductive system of Xiphinema americanum differs from that of other Xiphinema species in several respects. The ovary has branched oocytes surrounded by epithelial wall cells in which symbiotic bacteria are embedded. The oviduct has a long pars dilatata which is not clearly separated from the slender part; its wall is extensively folded and extendible. The sphincter between oviduct and uterus has a sinuous lumen and {\textquoteright}internal musculature{\textquoteright}. The uterus is extremely short and has a folded wall; the two uteri constitute together an extendible ovejector. Shortening of the uterus is considered to be an evolutionary trend in the X. americanum-group. (C) Orstom/Elsevier, Paris.}, isbn = {1164-5571}, author = {Coomans, A. and Claeys, M.} } @article {245, title = {Internal lectin binding patterns in the nematodes Caenorhabditis elegans, Panagrolaimus superbus and Acrobeloides maximus}, journal = {Fundamental and Applied NematologyFundamental and Applied Nematology}, volume = {20}, number = {2}, year = {1997}, note = {Borgonie, G VanDriessche, E Link, CD Claeys, M DeWaele, D Coomans, A}, pages = {173-186}, abstract = {Using ten different lectins, the binding patterns were studied in three free-living rhabditid nematodes : Caenorhabditis elegans, Panagrolaimus superbus, and Acrobeloides maximus. Although all the nematode tissues showed binding by one or more of the lectins used, considerable differences were noticed between the three nematode species. Yolk, four of the coelomocytes, and the oocytes bind most often with the lectins used. Although the intestinal brush border interacts with a lot of foreign materials, it stained only with few lectins. The lectin binding pattern of the yolk indicated that, at the time of incorporation of the yolk in embryos or shortly thereafter, a processing of the yolk occurs resulting in changes in lectin-binding characteristics of the yolk protein.}, isbn = {1164-5571}, author = {Borgonie, G. and VanDriessche, E. and Link, C. D. and Claeys, M. and DeWaele, D. and Coomans, A.} } @article {195, title = {Development and pharyngeal gland activities of Heterodera schachtii infecting Arabidopsis thaliana roots}, journal = {NematologyNematology}, volume = {4}, year = {2002}, note = {Tytgat, T De Meutter, J Vanholme, B Claeys, M Verreijdt, L Gheysen, G Coomans, APart 8}, pages = {899-908}, abstract = {As plant-nematode research continues to use the model host plant Arabidopsis thaliana more and more, we made a detailed life cycle study of Heterodera schachtii on this host, and investigated pharyngeal gland activities at the most crucial steps during the establishment of the parasitic interaction. In our experimental set up, in most cases induction of syncytia occurred during day 2, and the second moult during day 6. In pre-parasitic juveniles, both subventral glands contained numerous secretory granules, which gradually disappeared during intracellular migration of the juvenile through the roots. At the same time, both glands decreased in size and, after induction of the feeding cell, new kinds of secretory granules could be observed in the cytoplasm. During migration and induction of the feeding cell, the dorsal pharyngeal gland continuously increased in size. Secretory granules were already present in the dorsal gland of pre-parasitic juveniles, and a continuous synthesis of these granules was observed thereafter. Once the syncytium was induced, however, different types of secretory granules were formed.}, isbn = {1388-5545}, author = {Tytgat, T. and De Meutter, J. and Vanholme, B. and Claeys, M. and Verreijdt, L. and Gheysen, G. and Coomans, A.} } @article {210, title = {Evaluation of fixation methods for ultrastructural study of Caenorhabditis elegans embryos}, journal = {Microscopy Research and TechniqueMicroscopy Research and Technique}, volume = {49}, number = {2}, year = {2000}, note = {Vancoppenolle, B Claeys, M Borgonie, G Tytgat, T Coomans, A}, month = {Apr}, pages = {212-216}, abstract = {Various fixation methods for transmission electron microscopy (TEM) were tested on Caenorhabditis elegans embryos. By combining various techniques, using 3.4\% chitinase in combination with 1\% alpha-chymotripsin, we were able to establish a new fixation procedure that for the first time preserves both membranes and internal cellular ultrastructure of C. elegans embryos in different stages of development. This unique procedure will enable a hitherto unattainable standard for TEM research of C. elegans embryos. Sectioning of specific developmental stages fixed with this method allows a detailed study of ultrastructural aspects of embryogenesis. Microsc. Res. Tech. 49:212-216, 2000. (C) 2000 Wiley-Liss, Inc.}, isbn = {1059-910X}, author = {Vancoppenolle, B. and Claeys, M. and Borgonie, G. and Tytgat, T. and Coomans, A.} } @article {171, title = {Cuticular structure of three Bunonema species and first description of the male of B. penardi Stefanski, 1914 (Nematoda : Bunonematidae)}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Times Cited: 0 Article English Borgonie, G State Univ Ghent, Dept Biol, Nematol Sect, KL Ledeganckstr 35, B-9000 Ghent, Belgium Cited References Count: 38 889AI BRILL ACADEMIC PUBLISHERS PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS LEIDEN Part 4}, pages = {473-484}, abstract = {This study reanalyses some morphological and ultrastructural aspects of three Bunonema species. Specimens of B. penardi, B. hessi and B.franzi were studied using light microscopy and SEM. Bunonema franzi was also studied by TEM. The male of B. penardi is described, this being the first record of males in the genus Bunonema. Additional morphometric data on the females of this species are presented. SEM pictures show details of the deviant amphid position within the Bunonematidae. In contrast to earlier reports, our TEM results show that the evagination of the cuticle in ridges and tubercles is due to the thickening of the median zone of the cuticle. Ultrastructural details of the species-specific polygonal mesh network on the right body side are revealed. The rods that constitute this network lie above the epicuticle and are therefore extracuticular}, keywords = {BODY WALL, cuticle, FINE-STRUCTURE, GENUS, light microscopy, microscopy, morphology, Nematoda, PROTEIN, RHABDITIDA, SEM, STOMA, TEM, tubercle, ultrastructure, YOLK}, isbn = {1388-5545}, author = {Van Gansbeke, R. and Bert, W. and Govaerts, A. and Claeys, M. and Van Driessche, R. and Manhout, J. and Borgonie, G.} } @article {172, title = {Cuticular structure of three Bunonema species and first description of the male of B-penardi Stefanski, 1914 (Nematoda : Bunonematidae)}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Van Gansbeke, R Bert, W Govaerts, A Claeys, M Van Driessche, R Manhout, J Borgonie, GPart 4}, pages = {473-484}, abstract = {This study reanalyses some morphological and ultrastructural aspects of three Bunonema species. Specimens of B. penardi, B. hessi and B.franzi were studied using light microscopy and SEM. Bunonema franzi was also studied by TEM. The male of B. penardi is described, this being the first record of males in the genus Bunonema. Additional morphometric data on the females of this species are presented. SEM pictures show details of the deviant amphid position within the Bunonematidae. In contrast to earlier reports, our TEM results show that the evagination of the cuticle in ridges and tubercles is due to the thickening of the median zone of the cuticle. Ultrastructural details of the species-specific polygonal mesh network on the right body side are revealed. The rods that constitute this network lie above the epicuticle and are therefore extracuticular.}, isbn = {1388-5545}, author = {Van Gansbeke, R. and Bert, W. and Govaerts, A. and Claeys, M. and Van Driessche, R. and Manhout, J. and Borgonie, G.} } @article {173, title = {A new class of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in plant parasitic cyst nematodes}, journal = {Molecular Plant-Microbe InteractionsMolecular Plant-Microbe Interactions}, volume = {17}, number = {8}, year = {2004}, note = {Tytgat, T Vanholme, B De Meutter, J Claeys, M Couvreur, M Vanhoutte, I Gheysen, G Van Criekinge, W Borgonie, G Coomans, A Gheysen, G}, month = {Aug}, pages = {846-852}, abstract = {By performing cDNA AFLP on pre- and early parasitic juveniles, we identified genes encoding a novel type of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in the cyst nematode Heterodera schachtii. The proteins consist of three domains, a signal peptide for secretion, a mono-ubiquitin domain, and a short C-terminal positively charged domain. A gfp-fusion of this protein is targeted to the nucleolus in tobacco BY-2 cells. We hypothesize that the C-terminal peptide might have a regulatory function during syncytium formation in plant roots.}, isbn = {0894-0282}, author = {Tytgat, T. and Vanholme, B. and De Meutter, J. and Claeys, M. and Couvreur, M. and Vanhoutte, I. and Gheysen, G. and Van Criekinge, W. and Borgonie, G. and Coomans, A.} } @article {178, title = {High-pressure freezing and freeze substitution of gravid Caenorhabditis elegans (Nematoda : Rhabditida) for transmission electron microscopy}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Claeys, M Vanhecke, D Couvreur, M Tytgat, T Coomans, A Borgonie, GPart 3}, pages = {319-327}, abstract = {Because chemical fixatives have a profound negative influence on tissue morphology and antigenicity, alternative fixation methods must be applied for some purposes. In this work we used high-pressure freezing (HPF) followed by freeze substitution to maximally preserve antigenicity and morphology. We developed a pipette method for bringing living Caenorhabditis elegans nematodes into the HPF recipient. Using cellulose tubes, it is possible to select individual nematodes for fixation. We were able to HPF complete adults and preserve the morphology in an enhanced fashion compared to chemically fixed tissue. Cellular organelles, especially mitochondria, were much better preserved. Uterine embryos protected by the intact eggshell were excellently preserved without the need for elaborate techniques. Antigenicity with MH27 and ICB4 antiscra was tested. With the MH27 serum, an adequate, reproducible, specific binding pattern with chemically fixed tissue could Only be achieved using purified antibodies, whereas with high-pressure freezing, unpurified MH27 antisera was effective. For ICB4 antisera, a reproducible specific binding pattern was achieved at a concentration of primary antiserum 1000x lower than that for chemically fixed tissue.}, isbn = {1388-5545}, author = {Claeys, M. and Vanhecke, D. and Couvreur, M. and Tytgat, T. and Coomans, A. and Borgonie, G.} } @article {180, title = {The apical disposition of the Caenorhabditis elegans intestinal terminal web is maintained by LET-413}, journal = {Developmental BiologyDevelopmental Biology}, volume = {268}, number = {2}, year = {2004}, note = {Bossinger, O Fukushige, T Claeys, M Borgonie, G McGhee, JD}, month = {Apr}, pages = {448-456}, abstract = {We wish to understand how organ-specific structures assemble during embryonic development. In the present paper, we consider what determines the subapical position of the terminal web in the intestinal cells of the nematode Caenorhabditis elegans. The terminal web refers to the organelle-depleted, intermediate filament-rich layer of cytoplasm that underlies the apical microvilli of polarized epithelial cells. It is generally regarded as the anchor for actin rootlets protruding from the microvillar cores. We demonstrate that: (i) the widely used monoclonal antibody MH33 reacts (only) with the gut-specific intermediate filament protein encoded by the ifb-2 gene; (ii) IFB-2 protein accumulates near the gut lumen beginning at the lima bean stage of embryogenesis and remains associated with the gut lumen into adulthood; and (iii) as revealed by immunoelectron microscopy, IFB-2 protein is confined to a discrete circumferential subapical layer within the intestinal terminal web (known in nematodes as the "endotube"); this layer joins directly to the apical junction complexes that connect adjacent gut cells. To investigate what determines the disposition of the IFB-2-containing structure as the terminal web assembles during development, RNAi was used to remove the functions of gene products previously shown to be involved in the overall apicobasal polarity of the developing gut cell. Removal of dlg-1, ajm-1, or hmp-1 function has little effect on the overall position or continuity of the terminal web IFB-2-containing layer. In contrast, removal of the function of the let-413 gene leads to a basolateral expansion of the terminal web, to the point where it can now extend around the entire circumference of the gut cell. The same treatment also leads to concordant basolateral expansion of both gut cell cortical actin and the actin-associated protein ERM-1. LET-413 has previously been shown to be basolaterally located and to prevent the basolateral expansion of several individual apical proteins. In the present context, we conclude that LET-413 is also necessary to maintain the entire terminal web or brush border assembly at the apical surface of C elegans gut cells, a dramatic example of the so-called "fence" function ascribed to epithelial cell junctions. On the other hand, LET-413 is not necessary to establish this apical location during early development. Finally, the distance at which the terminal web intermediate filament layer lies beneath the gut cell surface (both apical and basolateral) must be determined independently of apical junction position. (C) 2004 Elsevier Inc. All rights reserved.}, isbn = {0012-1606}, author = {Bossinger, O. and Fukushige, T. and Claeys, M. and Borgonie, G. and McGhee, J. D.} } @article {186, title = {Lysosomal and pseudocoelom routing protects Caenorhabditis elegans from ricin toxicity}, journal = {NematologyNematology}, volume = {5}, year = {2003}, note = {Borgonie, G Link, CD Claeys, M Coomans, APart 3}, pages = {339-350}, abstract = {The resistance of the nematode Caenorhabditis elegans towards the highly potent toxin ricin has been studied. Incubation of C. elegans in ricin did not affect life span or progeny production. However, micro-injection of the ricin A-chain into the distal, syncitial gonad caused degeneration and sterility in test specimens, confirming that C. elegans ribosomes are sensitive. Using transmission electron microscopy, it was observed that ricin is effectively internalised into the intestinal cells. When pre-labelled with bold. the toxin reached only the lysosomes. When native toxin was used, the toxin was either routed to the lysosomes or underwent transcytosis to the pseudocoelomatic cavity and incorporation into embryos. None of the ricin reached either the trans Golgi network or the Golgi apparatus. considered essential for toxicity. The observed oral non-toxicity is therefore due to alternate sorting of the toxin. a mechanism not previously observed. The data indicate that, although ricin can opportunistically bind to, and be internalised by, cell surface receptors. these receptors are not sufficient to elicit toxicity.}, isbn = {1388-5545}, author = {Borgonie, G. and Link, C. D. and Claeys, M. and Coomans, A.} } @article {187, title = {Comparative morpho-anatomical studies of the female gonoduct within the Pratylenchidae (Nematoda : Tylenchina)}, journal = {NematologyNematology}, volume = {5}, year = {2003}, note = {Times Cited: 2 Article English Bert, W State Univ Ghent, Dept Biol, Ledeganckstr 35, B-9000 Ghent, Belgium Cited References Count: 33 712QZ BRILL ACADEMIC PUBLISHERS PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS LEIDEN Part 2}, pages = {293-306}, abstract = {The cellular morphology of the gonoduct of six Pratylenchus species, three Pratylenchoides species, Radopholus similis, Zygorylenchus guevarai, Hirschmanniella loofi and Nacobbus aberrans was revealed by dissection and light microscopy. Except for Nacobbus aberrans, all studied species show an overall similarity in gonoduct construction, i.e., an ovary often ending with a ring of cells, an oviduct formed from two rows of four cells and a 12-celled spermatheca followed by a tricolumella containing 16-24 cells. Pratylenchoides magnicauda and Z guevarai did not diverge from the other Pratylenchidae in this respect, although their gonoduct differs from that of Amplimerlinius and Meloidogyne, both formerly postulated as related genera. The spermatheca structure observed in N. aberrans has not been reported elsewhere in the Nematoda, although the uterus is similar to that reported within the Heteroderinae and Meloidogyninae and the uterus comprises more than 300 cells, enlarging from a tricolumella to a polycolumella. Transmission electron microscopy of Z guevarai revealed details of the cytoplasmatic contact between epithelial cells and the germ cells; a finger-like ovarian wall cell extension was found penetrating the oocyte. The oviduct lacks a preformed lumen and comprises eight cells with highly plicated cell membranes. The spermatheca is constructed from flattened wall cells and is followed by columnar uterus cells where evidence of eggshell formation was demonstrated}, keywords = {CELLS, electron microscopy, ELECTRON-MICROSCOPY, GENUS, gonad, gonoduct, HETERODERINAE, Hirschmanniella, LESION NEMATODE, light microscopy, MELOIDOGYNE, microscopy, morphology, Nacobbus, Nematoda, PENETRANS NEMATA, Pratylenchoides, Pratylenchus, REPRODUCTIVE-SYSTEM, SPERMATHECA, TEM, ultrastructure, Zygotylenchus}, isbn = {1388-5545}, author = {Bert, W. and Van Gansbeke, R. and Claeys, M. and Geraert, E. and Borgonie, G.} } @article {160, title = {The comparative cellular architecture of the female gonoduct among Tylenchoidea (Nematoda : Tylenchina)}, journal = {Journal of NematologyJournal of Nematology}, volume = {38}, number = {3}, year = {2006}, note = {Times Cited: 1 Article English Bert, W Univ Ghent, Dept Biol, Nematol Unit, B-9000 Ghent, Belgium Cited References Count: 30 115AX SOC NEMATOLOGISTS}, pages = {362-375}, abstract = {The cellular architecture of the female gonoduct of 68 nematode populations representing 42 species belonging to Tylenchidae, Belonolaimidae, Hoplolaimidae and Meloinema is shown to have an overall similarity in cellular gonoduct structure. The oviduct consists of two rows of four cells; the spermatheca is comprised of 10 to 20 cells, and the uterus cells, except in the case of Psilenchus, are arranged in four (Tylenchidae) or three (Belonolaimidae, Hoplolaimidae and Meloinema) regular rows. Although the genus Meloinema is classified within Meloidogynidae, its spermatheca is clearly hoplolaimid-like and lacks the spherical shape with lobe-like protruding cells typical of Meloidogyne. Detailed morphology of expelled gonoducts may provide a valuable character set in phylogenctic analysis, and the cellular morphology of the spermatheca appears to be a distinguishing feature at species level, especially in the genera Tylenchus and Geocenamus. Ultrastructural data on the oviduct-spermatheca region of Meloidogvne incognita complement light-microscopic (LM) results. The combination of LM of expelled organs and transmission electron microscopy (TEM) on selected sections is put for-ward as a powerful tool to combine three-dimensional knowledge with ultrastructural detail}, keywords = {analysis, Belonolaimidae, CELLS, electron microscopy, ELECTRON-MICROSCOPY, Evolution, GENITAL SYSTEM, GENUS, gonoduct, Hoplolaimidae, MELOIDOGYNE, Meloinema, microscopy, morphology, Nematoda, NEMATODE, ORDER TYLENCHIDA, POPULATIONS, REPRODUCTIVE-SYSTEM, SPERMATHECA, taxonomy, TEM, Tylenchidae, ultrastructure}, isbn = {0022-300X}, author = {Bert, W. and Claeys, M. and Borgonie, G.} } @article {161, title = {The comparative cellular architecture of the female gonoduct among Tylenchoidea (Nematoda : Tylenchina)}, journal = {Journal of NematologyJournal of Nematology}, volume = {38}, number = {3}, year = {2006}, note = {Bert, W. Claeys, M. Borgonie, G.}, month = {Sep}, pages = {362-375}, abstract = {The cellular architecture of the female gonoduct of 68 nematode populations representing 42 species belonging to Tylenchidae, Belonolaimidae, Hoplolaimidae and Meloinema is shown to have an overall similarity in cellular gonoduct structure. The oviduct consists of two rows of four cells; the spermatheca is comprised of 10 to 20 cells, and the uterus cells, except in the case of Psilenchus, are arranged in four (Tylenchidae) or three (Belonolaimidae, Hoplolaimidae and Meloinema) regular rows. Although the genus Meloinema is classified within Meloidogynidae, its spermatheca is clearly hoplolaimid-like and lacks the spherical shape with lobe-like protruding cells typical of Meloidogyne. Detailed morphology of expelled gonoducts may provide a valuable character set in phylogenctic analysis, and the cellular morphology of the spermatheca appears to be a distinguishing feature at species level, especially in the genera Tylenchus and Geocenamus. Ultrastructural data on the oviduct-spermatheca region of Meloidogvne incognita complement light-microscopic (LM) results. The combination of LM of expelled organs and transmission electron microscopy (TEM) on selected sections is put for-ward as a powerful tool to combine three-dimensional knowledge with ultrastructural detail.}, isbn = {0022-300X}, author = {Bert, W. and Claeys, M. and Borgonie, G.} } @article {163, title = {Unusual intestinal lamellae in the nematode Rhabditophanes sp KR3021 (Nematoda : Alloinematidae)}, journal = {Journal of MorphologyJournal of Morphology}, volume = {264}, number = {2}, year = {2005}, note = {Willems, M Houthoofd, W Claeys, M Couvreur, M Van Driessche, R Adriaens, D Jacobsen, K Borgonie, G}, month = {May}, pages = {223-232}, abstract = {The free-living nematode Rhabditophanes sp. has recently been placed in a clade of animal parasites and may be a unique example of a reversal to a nonparasitic lifestyle. Detailed morphological analysis of the intestine reveals the unusual and unique structure of splitting microlamellae forming a meshwork with cavities along the entire intestinal tract. Secretion vesicles were observed along the whole tract and along the length of the lamellae. It is suggested that these lamellae are adaptations to a different digestive strategy where low food availability and a low absorption surface are compensated for by maximizing the nutrient uptake efficiency along the entire length of the intestine. The likely reversal to a free-living life cycle may have caused drastic changes in diet, providing the necessary driving forces to such morphological changes. (c) 2005 Wiley-Liss, Inc.}, isbn = {0362-2525}, author = {Willems, M. and Houthoofd, W. and Claeys, M. and Couvreur, M. and Van Driessche, R. and Adriaens, D. and Jacobsen, K. and Borgonie, G.} } @article {119, title = {A new preparation method to study fresh plant structures with X-ray computed tomography}, journal = {Journal of Microscopy-OxfordJournal of Microscopy-Oxford}, volume = {233}, number = {1}, year = {2009}, note = {Leroux, O. Leroux, F. Bellefroid, E. Claeys, M. Couvreur, M. Borgonie, G. Van Hoorebeke, L. Masschaele, B. Viane, R.}, month = {Jan}, pages = {1-4}, abstract = {Since the development of X-ray computed tomography as a medical diagnostic tool, it was adapted and extended for many scientific applications, including plant structure research. As for many biological studies, sample preparation is of major importance to obtain good-quality images. Therefore, we present a new preparation method for fresh material which includes critical point drying and heavy metal staining. This technique enhances the contrast of fresh tissues, prevents artefacts such as tissue compression, and requires no embedding.}, isbn = {0022-2720}, author = {Leroux, O. and Leroux, F. and Bellefroid, E. and Claeys, M. and Couvreur, M. and Borgonie, G. and Van Hoorebeke, L. and Masschaele, B. and Viane, R.} } @article {123, title = {An endosymbiotic bacterium in a plant-parasitic nematode: Member of a new Wolbachia supergroup}, journal = {International Journal for ParasitologyInternational Journal for Parasitology}, volume = {39}, number = {9}, year = {2009}, note = {Haegeman, Annelies Vanholme, Bartel Jacob, Joachim Vandekerckhove, Tom T. M. Claeys, Myriam Borgonie, Gaetan Gheysen, Godelieve}, month = {Jul}, pages = {1045-1054}, abstract = {Wolbachia is an endosymbiotic bacterium widely present in arthropods and animal-parasitic nematodes. Despite previous efforts, it has never been identified in plant-parasitic nematodes. Random sequencing of genes expressed by the burrowing nematode Radopholus similis resulted in several sequences with similarity to Wolbachia genes. The presence of a Wolbachia-like endosymbiont in this plant-parasitic nematode was investigated using both morphological and molecular approaches. Transmission electron microscopy, fluorescent immunolocalisation and staining with DAPI confirmed the presence of the endosymbiont within the reproductive tract of female adults. 16S rDNA,ftsZ and groEL gene sequences showed that the endosymbiont of R. similis is distantly related to the known Wolbachia supergroups. Finally, based on our initial success in finding sequences of this endosymbiont by screening an expressed sequence tag (EST) dataset, all nematode ESTs were mined for Wolbachia-like sequences. Although the retained sequences belonged to six different nematode species, R. similis was the only plant-parasitic nematode with traces of Wolbachia. Based on our phylogenetic study and the current literature we designate the endosymbiont of R. similis to a new supergroup (supergroup 1) rather than considering it as a new species. Although its role remains unknown, the endosymbiont was found in all individuals tested, pointing towards an essential function of the bacteria. (C) 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.}, isbn = {0020-7519}, author = {Haegeman, A. and Vanholme, B. and Jacob, J. and Vandekerckhove, T. T. M. and Claeys, M. and Borgonie, G. and Gheysen, G.} } @article {84, title = {Spermatogenesis and the structure of the testes in Nemertodermatida}, journal = {ZoomorphologyZoomorphology}, volume = {130}, number = {4}, year = {2011}, note = {Boone, Mieke Bert, Wim Claeys, Myriam Houthoofd, Wouter Artois, Tom}, month = {Dec}, pages = {273-282}, abstract = {The ultrastructure of the testes in two representatives of the enigmatic taxon Nemertodermatida was studied using transmission electron microscopy. Nemertoderma westbladi has paired testes, which are delineated by lining cells. Within each testis, different follicles, each surrounded by a membrane-like structure, are found. Flagellophora apelti has genuinely follicular testes, consisting of several follicles, each containing a certain stage of spermatogenesis. As the gametes are not enclosed by a structure that can be called a true gonad, the structure of the testes differs from most bilaterian animals, but resembles the organization of gametogenic areas of ctenophores. Each stage of spermatogenesis in F. apelti is described, enabling the inference of the origin of the structures seen in mature spermatozoa. The overall structure of the mature spermatozoa is similar in all nemertodermatids and unique within the Metazoa: an elongated head containing the nucleus; a middle piece containing an axoneme, mitochondrial derivatives and in F. apelti granular derivatives; and a flagellar tail.}, isbn = {0720-213X}, author = {Boone, M. and Bert, W. and Claeys, M. and Houthoofd, W. and Artois, T.} } @article {97, title = {A Wolbachia-like endosymbiotic bacterium in the plant-parasitc nematode Rhadopholus similis}, journal = {Journal of NematologyJournal of Nematology}, volume = {42}, number = {3}, year = {2010}, note = {Haegeman Annelies, B. Vanholme Jacob, J. Vandekerckhove, T. T. M. Claeys, M. Borgonie, G. Gheysen, G.}, month = {Sep}, pages = {245-245}, isbn = {0022-300X}, author = {Haegeman, and Annelies, B. V. and Jacob, J. and Vandekerckhove, T. T. M. and Claeys, M. and Borgonie, G. and Gheysen, G.} } @article {107, title = {Ontogeny of the Complex Sperm in the Macrostomid Flatworm Macrostomum lignano (Macrostomorpha, Rhabditophora)}, journal = {Journal of MorphologyJournal of Morphology}, volume = {270}, number = {2}, year = {2009}, note = {Willems, Maxime Leroux, Frederic Claeys, Myriam Boone, Mieke Mouton, Stijn Artois, Tom Borgonie, Gaetan}, month = {Feb}, pages = {162-174}, abstract = {Spermiogenesis in Macrostomum lignano (Macrostomorpha, Rhabditophora) is described using light- and electron microscopy of the successive stages in sperm development. Ovoid spermatids develop to highly complex, elongated sperm possessing an undulating distal (anterior) process (or "feeler"), bristles, and a proximal (posterior) brush. In particular, we present a detailed account of the morphology and ontogeny of the bristles, describing for the first time the formation of a highly specialized bristle complex consisting of several parts. This complex is ultimately reduced when sperm are mature. The implications of the development of this bristle complex on both sperm maturation and the evolution and function of the bristles are discussed. The assumed homology between bristles and flagellae questioned. J. Morphol. 270:162-174, 2009. (C) 2008 Wiley-Liss, Inc.}, isbn = {0362-2525}, author = {Willems, M. and Leroux, F. and Claeys, M. and Boone, M. and Mouton, S. and Artois, T. and Borgonie, G.} } @article {72, title = {Mature spermatozoa of Brevibucca sp (Nematoda: Rhabditida: Brevibuccidae)}, journal = {Russian Journal of NematologyRussian Journal of NematologyRussian Journal of Nematology}, volume = {19}, number = {2}, year = {2011}, note = {ISI Document Delivery No.: 895YZTimes Cited: 0Cited Reference Count: 30Yushin, Vladimir V. Claeys, Myriam Houthoofd, WouterEUMAINE [RFBR 11-04-00368, RFBR 11-04-98555, FEB RAS 09-III-A-06-216]; RF government [2010-220-01-180]This research was supported in part by EUMAINE; RFBR 11-04-00368; RFBR 11-04-98555; FEB RAS 09-III-A-06-216 and RF government grant 2010-220-01-180. The authors are grateful to D.V. Fomin (Institute of Marine Biology, Vladivostok) for technical assistance.Russian acad sci, inst parasitologyMoscow}, pages = {131-138}, type = {Article}, abstract = {Mature spermatozoa found in the female gonoduct of the nematode Brevibucca sp. (Brevibuccidae, Rhabditida) were studied with transmission electron microscopy. As in other nematodes, the spermatozoa in Brevibucca sp. represent an aberrant type of male gametes characterised by the absence of an axoneme and an acrosome. Mature spermatozoa of Brevibucca sp. are amoeboid bipolar cells Ca 4-4.5 mu m diam.; each cell is subdivided into a main cell body and a pseudopod devoid of organelles. The main cell body includes a condensed nucleus, many mitochondria and so-called {\textquoteright}membranous organelles{\textquoteright} (MO). These unique organelles are characteristic of developing, as well as of mature, spermatozoa of many nematodes. The MO in Brevibucca sp. sperm resemble large (ca 0.5 diam.) vesicles with transparent content and a system of internal finger-like projections of the outer membrane. Each MO is joined to the plasmalemma of the main cell body and is open to the intercellular exterior via a pore. Each spermatozoon has a prominent pseudopod filled with the filamentous components of the cytoskeleton. The structure and development of the rhabditid (order Rhabditida apud De Ley \& Blaxter, 2002) sperm is somewhat conserved throughout the order. That is, the general pattern of spermatozoon recognized as "rhabditid" in Brevibucca sp. is similarly expressed in Spiruromorpha, Ascaridomorpha, Panagrolaimomorpha, Tylenchomorpha and Rhabditomorpha. Thus, such conservation lacks phylogenetic pointers at the scale of order. The spermatozoa of the rhabditid pattern observed also in Brevibucca sp. may be considered as an ancestral or symplesiomorphic character for several clades of the order Rhabditida.}, keywords = {caenorhabditis-elegans, dimorphism, female gonoduct, fibrous bodies, filarioidea, membranous organelles, mitochondria, phylogenetic-relationships, phylogeny, pseudopod, sperm development, spermatogenesis, sphaerularioidea, steinernematidae, tylenchomorpha, ultrastructure}, isbn = {0869-6918}, author = {Yushin, V. V. and Claeys, M. and Houthoofd, W.} } @article {41, title = {Interaction of Aspergillus fumigatus conidia with Acanthamoeba castellanii parallels macrophage{\textendash}fungus interactions}, journal = {Environmental MicrobiologyEnvironmental Microbiology}, volume = {Article first published online: 22 JUL 2013 | DOI: 10.1111/1758-2229.12082}, year = {2013}, author = {Van Waeyenberghe, L. and Bar{\'e}, J. and Pasmans, F. and Claeys, M. and Bert, W. and Haesebrouck, F. and Houf, K. and Martel, A.} } @article {20, title = {Transmission electron microscopy sample preparation protocols for ultrastructural study of cysts of free-living protozoa}, journal = {BiotechniquesBiotechniques}, year = {2015}, author = {Lambrecht, E. and Bar{\'e}, J. and Bert, W. and Sabbe, K. and Claeys, M. and Chavatte, N. and Houf, K.} }