scholarly journals Diversity and Host Relationships of the Mycoparasite Sepedonium (Hypocreales, Ascomycota) in Temperate Central Chile

2021 ◽  
Vol 9 (11) ◽  
pp. 2261
Author(s):  
Josefa Binimelis-Salazar ◽  
Angélica Casanova-Katny ◽  
Norbert Arnold ◽  
Celia A. Lima ◽  
Heraldo V. Norambuena ◽  
...  
Keyword(s):  
Central Chile ◽  
Fungal Host ◽  
Specific Distribution ◽  
Nothofagus Forests ◽  
Mycoparasitic Fungus ◽  
Timber Plantations ◽  
Host Parasite ◽  
Species Descriptions ◽  
New Evidence

We present the first major survey of regional diversity, distribution and host-association of Sepedonium. Whereas the rather scarce worldwide records of this mycoparasitic fungus suggested no specific distribution pattern of most species before, we provide new evidence of endemic and specific host-parasite guilds of Sepedonium in Southern South America, including the description of a new species. The corresponding inventory was performed in temperate central Chile. The regional landscape, a mosaic of exotic timber plantations and remnants of native Nothofagus forests, facilitates a unique combination of endemic and adventitious Boletales hosts. During a two-year survey, 35 Sepedonium strains were isolated and cultured from infected basidiomata of allochthonous Chalciporus piperatus, Paxillus involutus, Rhizopogon spp. and Suillus spp., as well as from the native Boletus loyita, B. loyo, B. putidus and Gastroboletus valdivianus. Taxonomic diagnosis included morphology of conidia and conidiophores, sequences of ITS, RPB2 and EF1 molecular markers and characteristics of in vitro cultures. Phylogenetic reconstructions were performed using Bayesian methods. Four Sepedonium species could be identified and characterized, viz.: S. ampullosporum, S. chrysospermum, S. laevigatum and the newly described species S. loyorum. The most frequent species on introduced Boletales was S. ampullosporum, followed by S. chrysospermum and S. laevigatum. S. loyorum sp. nov. was found exclusively on native boletacean hosts, separated from its closest relative S. chalcipori by micromorphological and molecular attributes. Species descriptions and identification keys are provided. Ecological and biogeographical aspects of endemic and allochthonous symbiotic units consisting of mycoparasite, ectomycorrhizal fungal host and respective mycorrhizal tree are discussed.

scholarly journals Schistosoma mansonicercariae experience influx of macromolecules during skin penetration

Parasitology ◽  
2009 ◽  
Vol 136 (11) ◽  
pp. 1257-1267 ◽  
Author(s):  
J. THORNHILL ◽  
P. M. Z. COELHO ◽  
P. McVEIGH ◽  
A. MAULE ◽  
A. D. JURBERG ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Lucifer Yellow ◽  
Surface Membrane ◽  
Skin Penetration ◽  
Pharyngeal Muscle ◽  
Novel Host ◽  
Host Parasite ◽  
Fluorescent Molecules ◽  
Germinal Mass

SUMMARYWe have observed that when cercariae penetrate the skin of mice, there is influx into their tissues of Lucifer Yellow and certain labelled molecules of up to 20 kDa molecular weight. This observation was made using a variety of fluorescent membrane-impermeant compounds injected into the skin before the application of cercariae. This unexpected phenomenon was investigated further by transforming cercariaein vitroin the presence of the membrane-impermeant compounds and examining the distribution by microscopy. In schistosomula derived from this procedure, the nephridiopore and surface membrane were labelled while the pre- and post-acetabular glands were not labelled. The region associated with the oesophagus within the pharyngeal muscle clearly contained the fluorescent molecules, as did the region adjacent to the excretory tubules and the germinal mass. We used cercariae stained with carmine to aid identification of regions labelled with Lucifer Yellow. Although the mechanism of this influx is unclear, the observation is significant. From it, we can suggest an hypothesis that, during skin penetration, exposure of internal tissues of the parasite to external macromolecules represents a novel host-parasite interface.

Cellular Samurai: katanin and the severing of microtubules

2000 ◽  
Vol 113 (16) ◽  
pp. 2821-2827 ◽  
Author(s):  
L. Quarmby
Keyword(s):  
Epithelial Cells ◽  
Essential Role ◽  
Aaa Atpase ◽  
C Elegans ◽  
Microtubule Severing ◽  
Biochemical Studies ◽  
New Evidence

Recent biochemical studies of the AAA ATPase, katanin, provide a foundation for understanding how microtubules might be severed along their length. These in vitro studies are complemented by a series of recent reports of direct in vivo observation of microtubule breakage, which indicate that the in vitro phenomenon of catalysed microtubule severing is likely to be physiological. There is also new evidence that microtubule severing by katanin is important for the production of non-centrosomal microtubules in cells such as neurons and epithelial cells. Although it has been difficult to establish the role of katanin in mitosis, new genetic evidence indicates that a katanin-like protein, MEI-1, plays an essential role in meiosis in C. elegans. Finally, new proteins involved in the severing of axonemal microtubules have been discovered in the deflagellation system of Chlamydomonas.

New Nesting Records and Breeding Ecology Observations of Rufous-legged Owls in the Mediterranean Temperate Forest of Central Chile

2021 ◽  
Author(s):  
Martín A. H. Escobar ◽  
M. Angélica Vukasovic ◽  
Jorge A. Tomasevic ◽  
Sandra V. Uribe ◽  
Ana M. Venegas ◽  
...  
Keyword(s):  
Clutch Size ◽  
Temperate Forest ◽  
Breeding Ecology ◽  
Ecological Data ◽  
Central Chile ◽  
Monterey Pine ◽  
Nestling Diet ◽  
Nestling Period ◽  
Nothofagus Forests ◽  
Southern Beech

ABSTRACT The Rufous-legged Owl (Strix rufipes) is the southernmost Strix owl species and its breeding ecology remains little known. We report new observations on the species' breeding ecology, including clutch size, egg size, duration of the incubation and nestling periods, and nestling diet. We conducted our observations on nests found during the summers of 1999 through 2004 in a forestry landscape of central Chile, dominated by Monterey pine (Pinus radiata) plantations with intermixed fragments of native southern beech (Nothofagus) forests. Clutch size was two eggs (n = 2 nests), with one egg larger than the other (mean = 48.8 × 40.1 mm). The incubation period was 30 d and the nestling period 34 d. We analyzed 10 pellets from nestling owls and identified 45 prey items, mostly dominated by large beetles, grasshoppers, and rodents (native and exotic). This information, though based on a limited number of nests, provides baseline ecological data that can inform future studies.

scholarly journals Impact of extracellular matrix properties on neuroblastoma genomic heterogeneity

2020 ◽  
Author(s):  
Amparo López-Carrasco ◽  
Susana Martín-Vañó ◽  
Rebeca Burgos-Panadero ◽  
Ezequiel Monferrer ◽  
Ana P Berbegall ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
High Risk ◽  
Cell Lines ◽  
Neuroblastoma Cell ◽  
Chromosome 9 ◽  
Future Research ◽  
Knock Out ◽  
Specific Distribution

Abstract Background Increased tissue stiffness is a common feature of malignant solid tumors, often associated with metastasis and poor patient outcomes. Vitronectin, as an extracellular matrix anchorage glycoprotein related to a stiff matrix, is present in a particularly increased quantity and specific distribution in high-risk neuroblastoma. Furthermore, as cells can sense and transform the proprieties of the extracellular matrix into chemical signals through mechanotransduction, genotypic changes related to stiffness are possible. Methods We have applied high density SNPa and NGS techniques to in vivo and in vitro models (orthotropic xenograft vitronectin knock-out mice and 3D bioprinted hydrogels with different stiffness) using two representative neuroblastoma cell lines (the MYCN amplified SK-N-BE(2) and the ALK mutated SH-SY5Y), to discern how tumor genomics patterns and clonal heterogeneity of both cell lines are affected. Results We describe a remarkable subclonal selection of some genomic aberrations in SK-N-BE(2) cells grown in knock-out vitronectin xenograft mice that also emerged when cultured for long times in stiff hydrogels. Specially, we detected an enlarged subclonal cell population with chromosome 9 aberrations in both models. Similar abnormalities were found in human high-risk neuroblastoma with MYCN amplification. Genomics of the SH-SY5Y cell line remained stable when cultured in both models. Conclusions Focus on heterogeneous intratumor segmental chromosome aberrations and mutations, as a mirror image of tumor microenvironment, is a vital area of future research.

scholarly journals Connectivity and network state-dependent recruitment of long-range VIP-GABAergic neurons in the mouse hippocampus

2018 ◽  
Author(s):  
Ruggiero Francavilla ◽  
Vincent Villette ◽  
Xiao Luo ◽  
Simon Chamberland ◽  
Einer Muñoz-Pino ◽  
...  
Keyword(s):  
Molecular Diversity ◽  
Pyramidal Cells ◽  
Functional Specialization ◽  
Gabaergic Interneurons ◽  
Long Distance ◽  
State Dependent ◽  
Mouse Hippocampus ◽  
Ca1 Area ◽  
New Evidence

AbstractGABAergic interneurons in the hippocampus provide for local and long-distance coordination of neurons in functionally connected areas. Vasoactive intestinal peptide-expressing (VIP+) interneurons occupy a distinct niche in circuitry as many of them specialize in innervating GABAergic cells, thus providing network disinhibition. In the CA1 hippocampus, VIP+ interneuron-selective cells target local interneurons. Here, we discovered a novel type of VIP+ neuron whose axon innervates CA1 and also projects to the subiculum (VIP-LRPs). VIP-LRPs showed specific molecular properties and targeted interneurons within the CA1 area but both interneurons and pyramidal cells within subiculum. They were interconnected through gap junctions but demonstrated sparse spike coupling in vitro. In awake mice, VIP-LRPs decreased their activity during theta-run epochs and were more active during quiet wakefulness but not coupled to sharp-wave ripples. Together, the data provide new evidence for VIP interneuron molecular diversity and functional specialization in controlling cell ensembles along the hippocampo-subicular axis.

scholarly journals Dual RNA-Seq Analysis of Trichophyton rubrum and HaCat Keratinocyte Co-Culture Highlights Important Genes for Fungal-Host Interaction

Genes ◽  
2018 ◽  
Vol 9 (7) ◽  
pp. 362 ◽  
Author(s):  
Monise Petrucelli ◽  
Kamila Peronni ◽  
Pablo Sanches ◽  
Tatiana Komoto ◽  
Josie Matsuda ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Trichophyton Rubrum ◽  
Glyoxylate Cycle ◽  
Human Keratinocytes ◽  
Rna Seq ◽  
Fungal Host ◽  
Host Interaction ◽  
Genes Encoding ◽  
Hacat Keratinocyte

The dermatophyte Trichophyton rubrum is the major fungal pathogen of skin, hair, and nails that uses keratinized substrates as the primary nutrients during infection. Few strategies are available that permit a better understanding of the molecular mechanisms involved in the interaction of T. rubrum with the host because of the limitations of models mimicking this interaction. Dual RNA-seq is a powerful tool to unravel this complex interaction since it enables simultaneous evaluation of the transcriptome of two organisms. Using this technology in an in vitro model of co-culture, this study evaluated the transcriptional profile of genes involved in fungus-host interactions in 24 h. Our data demonstrated the induction of glyoxylate cycle genes, ERG6 and TERG_00916, which encodes a carboxylic acid transporter that may improve the assimilation of nutrients and fungal survival in the host. Furthermore, genes encoding keratinolytic proteases were also induced. In human keratinocytes (HaCat) cells, the SLC11A1, RNASE7, and CSF2 genes were induced and the products of these genes are known to have antimicrobial activity. In addition, the FLG and KRT1 genes involved in the epithelial barrier integrity were inhibited. This analysis showed the modulation of important genes involved in T. rubrum–host interaction, which could represent potential antifungal targets for the treatment of dermatophytoses.

scholarly journals Analysis of Plasmodium vivax schizont transcriptomes from field isolates reveals heterogeneity of expression of genes involved in host-parasite interactions

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sasha V. Siegel ◽  
Lia Chappell ◽  
Jessica B. Hostetler ◽  
Chanaki Amaratunga ◽  
Seila Suon ◽  
...  
Keyword(s):  
Plasmodium Vivax ◽  
Ex Vivo ◽  
Culture Method ◽  
Surface Proteins ◽  
Parasite Development ◽  
Field Isolates ◽  
Host Parasite Interactions ◽  
Short Period ◽  
Host Parasite

Abstract Plasmodium vivax gene regulation remains difficult to study due to the lack of a robust in vitro culture method, low parasite densities in peripheral circulation and asynchronous parasite development. We adapted an RNA-seq protocol “DAFT-seq” to sequence the transcriptome of four P. vivax field isolates that were cultured for a short period ex vivo before using a density gradient for schizont enrichment. Transcription was detected from 78% of the PvP01 reference genome, despite being schizont-enriched samples. This extensive data was used to define thousands of 5′ and 3′ untranslated regions, some of which overlapped with neighbouring transcripts, and to improve the gene models of 352 genes, including identifying 20 novel gene transcripts. This dataset has also significantly increased the known amount of heterogeneity between P. vivax schizont transcriptomes from individual patients. The majority of genes found to be differentially expressed between the isolates lack Plasmodium falciparum homologs and are predicted to be involved in host-parasite interactions, with an enrichment in reticulocyte binding proteins, merozoite surface proteins and exported proteins with unknown function. An improved understanding of the diversity within P. vivax transcriptomes will be essential for the prioritisation of novel vaccine targets.

scholarly journals Malaria and red cell genetic defects

Blood ◽  
1989 ◽  
Vol 74 (4) ◽  
pp. 1213-1221 ◽  
Author(s):  
RL Nagel ◽  
EF Jr Roth
Keyword(s):  
Culture System ◽  
Potential Role ◽  
Dna Analysis ◽  
Red Cell ◽  
Metabolic Products ◽  
Recombinant Technology ◽  
Host Parasite ◽  
Made In

Abstract The study of inherited RBC resistance to malaria has increased our knowledge of the biochemistry and physiology of the host-parasite interaction and suggested potential sites for therapeutic intervention. Discovery by Jensen and Trager of the in vitro culture system for P falciparum has facilitated research in this area. Known RBC defects may affect invasion, growth, or merozoite liberation (Fig 1). Significant advances made in understanding mechanisms underlying protection against malaria should not obscure the fact that the data are far from complete. More knowledge is needed about the influence of the erythrocyte cytoskeleton on invasion and growth of parasites as well as the potential role of phospholipids, erythrocyte enzymes other than G6PD, or other metabolic products. Application of DNA analysis and recombinant technology may have an increasing impact on study of the interaction of RBC defects with malarial parasites.

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