23 research outputs found
Subnanometer structure of an enveloped virus fusion complex on viral surface reveals new entry mechanisms
No full textParamyxoviruses-including important pathogens like parainfluenza, measles, and Nipah viruses-use a recep-tor binding protein [hemagglutinin-neuraminidase (HN) for parainfluenza] and a fusion protein (F), acting in a complex, to enter cells. We use cryo-electron tomography to visualize the fusion complex of human parainflu-enza virus 3 (HN/F) on the surface of authentic clinical viruses at a subnanometer resolution sufficient to answer mechanistic questions. An HN loop inserts in a pocket on F, showing how the fusion complex remains in a ready but quiescent state until activation. The globular HN heads are rotated with respect to each other: one down-ward to contact F, and the other upward to grapple cellular receptors, demonstrating how HN/F performs dis-tinct steps before F activation. This depiction of viral fusion illuminates potentially druggable targets for paramyxoviruses and sheds light on fusion processes that underpin wide-ranging biological processes but have not been visualized in situ or at the present resolution
Leaf epidermal characteristics of medicinal species of the genus Solanum L. (Solanaceae) of the Biogeography Parnpean province
No full textSe presenta el análisis de las características de las hojas de Solanum amygdalifolium Steud., S. chenopodioides Lam., S. commersonii Dunal ex Poir. subsp. commersonii, S. eleagnifolium Cav., S. glaucophyllum Desf., S. granuloso-leprosum Dunal, S. pilcomayense Morong var. pilcomayense, S. pseudocapsicum L., S. sisymbriifolium Lam. var. sisymbriifolium y S. sublobatum Willd. ex Schult. Estas especies crecen en el Este de Argentina, Uruguay y Brasil (mitad austral de Rio Grande do Sul) y son utilizadas en medicina popular. En cada una de ellas se trata su identidad botánica, su descripción morfológica, el modelo de la pared anticlinal de las células epidérmicas, su tamaño y número por campo, el tamaño de los estomas y su número por campo, el índice estomático y la densidad y tipos de tricomas presentes. Los resultados se complementan con ilustraciones y tablas originales del autor. Por último, se incluye una clave dicotómica para la determinación de dichas especies, sobre la base de las características estudiadas.This work deals with the epidermal leaf characteristics of Solanum amygdalifolium Steud., S. chenopodioides Lam., S. commersonii Dunal ex Poir. subsp. commersonii, S. eleagnifolium Cav., S. glaucophyllum Desf., S. granuloso-leprosum Dunal, S. pilcomayense Morong var. pilcomayense, S. pseudocapsicum L., S. sisymbriifolium Lam. var. sisymbriifolium, and S. sublobatum Willd. ex Schult. These species are distributed in the East of Argentina, Uruguay and South of Río Grande do Sul, Brazil, and are used in popular medicine. Botanical identity, morphology, anticlinal cell wall pattems, epidermal cell dimensions and number per field, stomata size and number per field, stomatal index and trichome density and type, were analyzed. Results include ilustrations and tables from the author. Finally, a key that allows to distinguish the studied species is provided.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Leaf epidermal characteristics of medicinal species of the genus Solanum L. (Solanaceae) of the Biogeography Parnpean province
No full textSe presenta el análisis de las características de las hojas de Solanum amygdalifolium Steud., S. chenopodioides Lam., S. commersonii Dunal ex Poir. subsp. commersonii, S. eleagnifolium Cav., S. glaucophyllum Desf., S. granuloso-leprosum Dunal, S. pilcomayense Morong var. pilcomayense, S. pseudocapsicum L., S. sisymbriifolium Lam. var. sisymbriifolium y S. sublobatum Willd. ex Schult. Estas especies crecen en el Este de Argentina, Uruguay y Brasil (mitad austral de Rio Grande do Sul) y son utilizadas en medicina popular. En cada una de ellas se trata su identidad botánica, su descripción morfológica, el modelo de la pared anticlinal de las células epidérmicas, su tamaño y número por campo, el tamaño de los estomas y su número por campo, el índice estomático y la densidad y tipos de tricomas presentes. Los resultados se complementan con ilustraciones y tablas originales del autor. Por último, se incluye una clave dicotómica para la determinación de dichas especies, sobre la base de las características estudiadas.This work deals with the epidermal leaf characteristics of Solanum amygdalifolium Steud., S. chenopodioides Lam., S. commersonii Dunal ex Poir. subsp. commersonii, S. eleagnifolium Cav., S. glaucophyllum Desf., S. granuloso-leprosum Dunal, S. pilcomayense Morong var. pilcomayense, S. pseudocapsicum L., S. sisymbriifolium Lam. var. sisymbriifolium, and S. sublobatum Willd. ex Schult. These species are distributed in the East of Argentina, Uruguay and South of Río Grande do Sul, Brazil, and are used in popular medicine. Botanical identity, morphology, anticlinal cell wall pattems, epidermal cell dimensions and number per field, stomata size and number per field, stomatal index and trichome density and type, were analyzed. Results include ilustrations and tables from the author. Finally, a key that allows to distinguish the studied species is provided.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Discovery of Novel Viruses in Arachnids
No full textabstract: Arachnids belong to the phylum Arthropoda, the largest phylum in the animal kingdom. Ticks are blood-feeding arachnids that vector numerous pathogens of significant medical and veterinary importance, while scorpions have become a common concern in urban desert cities due to the high level of toxicity in their venom. To date, viruses associated with arachnids have been under sampled and understudied. Here viral metagenomics was used to explore the diversity of viruses present in ticks and scorpions. American dog ticks (Dermacentor variabilis) and blacklegged ticks (Ixodes scapularis) were collected in Pennsylvania while one hairy scorpion (Hadrurus arizonensis) and four bark scorpions (Centruroides sculpturatus) were collected in Phoenix. Novel viral genomes described here belong to the families Polyomaviridae, Anelloviridae, Genomoviridae, and a newly proposed family, Arthropolviridae.
Polyomaviruses are non-enveloped viruses with a small, circular double-stranded DNA (dsDNA) genomes that have been identified in a variety of mammals, birds and fish and are known to cause various diseases. Arthropolviridae is a proposed family of circular, large tumor antigen encoding dsDNA viruses that have a unidirectional genome organization. Genomoviruses and anelloviruses are ssDNA viruses that have circular genomes ranging in size from 2–2.4 kb and 2.1–3.8 kb, respectively. Genomoviruses are ubiquitous in the environment, having been identified in a wide range of animal, plant and environmental samples, while anelloviruses have been associated with a plethora of animals.
Here, 16 novel viruses are reported that span four viral families. Eight novel polyomaviruses were recovered from bark scorpions, three arthropolviruses were recovered from dog ticks and one arthropolvirus from a hairy scorpion. Viruses belonging to the families Polyomaviridae and Arthropolviridae are highly divergent. This is the first more extensive study of these viruses in arachnids. Three genomoviruses were recovered from both dog and deer ticks and one anellovirus was recovered from deer ticks, which are the first records of these viruses being recovered from ticks. This work highlights the diversity of dsDNA and ssDNA viruses in the arachnid population and emphasizes the importance of performing viral surveys on these populations.Dissertation/ThesisMasters Thesis Microbiology 201
076 - James Zachary Curlin
No full textHuman Immunodeficiency Virus (HIV) is believed to have arisen in humans as a result of multiple independent cross-species exposures to Simian Immunodeficiency Viruses. Here the serial passaging of SIV in humanized mice across several generations recapitulates the genetic changes that make have facilitated such cross-species transmissions. Viral adaptation to the hu-mice was determined via qRT-PCR analysis of plasma viral loads and observation of CD4+ T-cell depletion. SIVs at various stages of adaptation from different generations were analyzed through Next Generation Sequencing (NGS). Many non-synonymous mutations were observed across each passage that may be responsible for improved cross-species transmission and adaptation
The Role of Innate APOBEC3G and Adaptive AID Immune Responses in HLA-HIV/SIV Immunized SHIV Infected Macaques
No full textThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
The effects of genome expansion on transposable element diversity in salamanders
No full text2021 Summer.Includes bibliographical references.Transposable elements (TEs) are repetitive sequences of DNA that replicate and proliferate throughout genomes. Taken together, all the TEs in a genome form a diverse community of sequences, which can be studied to draw conclusions about genome evolution. TE diversity can be measured using ecological models for species distribution that consider richness and evenness of communities. It is currently not well studied how genome expansion impacts the diversity of transposable elements. However, there are a few models that predict TE diversity decreasing as genomes expand due to varying mechanisms such as selection against ectopic recombination and competition between TEs and silencing machinery. Salamanders are known to have some of the largest vertebrate genomes. Salamanders of the genus Plethodon in particular have very large genomes consisting of high levels of TEs, with sizes ranging from 30 to 70 Gigabases (Gb). Here, I use Oxford Nanopore sequencing to generate low-coverage genomic sequences for four species of Plethodon that encompass two independent genome expansion events, one in the eastern clade and one in the western clade: Plethodon glutinosus (41.4 Gb), P. cinereus (30.5 Gb), P. idahoensis (71.7 Gb), and P. vehiculum (50.5 Gb). I classified the TEs in these datasets using RepeatMasker and DnaPipeTE and found ~51 superfamilies which accounted for 27-32% of the genomes. For each genome I calculated the Simpson's and Shannon's diversity indices to quantify diversity, taking into account both TE richness and evenness. In all cases, the values for Simpson's index were within 0.75 and 0.79, and for Shannon's index all species were within 1.88 and 1.99. We conclude that once genomes reach large sizes, they maintain high levels of TE diversity at the superfamily level, in contrast to observations made by previous studies done on smaller genomes
Porcine endogenous retroviruses PERV A and A/C recombinant are insensitive to a range of divergent mammalian TRIM5 proteins including human TRIM5
No full textThe potential risk of cross-species transmission of porcine endogenous retroviruses (PERV) to humans has slowed the development of xenotransplantation, using pigs as organ donors. Here, we show that PERVs are insensitive to restriction by divergent TRIM5{alpha} molecules despite the fact that they strongly restrict a variety of divergent lentiviruses. We also show that the human PERV A/C recombinant clone 14/220 reverse transcribes with increased efficiency in human cells, leading to significantly higher infectivity. We conclude that xenotransplantation studies should consider the danger of highly infectious TRIM5{alpha}-insensitive human-tropic PERV recombinants
Exploring the Hemp Virome and Assessing Hemp Germplasm for Resistance to an Emerging Pathogen
No full textHemp (Cannabis sativa L., 97% nucleotide identity to their nearest GenBank accessions. As the growing season progressed, viral incidence and the number of viral species increased. We observed similar and unique viromes between individual cultivars from the same field. Given the prevalence of BCTV in the virome and its prevalence across the western United States, 13 genotypes of hemp were screened for resistance to this pathogen. Two genotypes (4587 and 4710) had a lower BCTV log copy number and disease index than others. Our study provides initial evidence of the diversity of viral communities in hemp across Colorado and provides impetus for developing accurate detection methods and screening for host resistance. [Figure: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license
Assessment of anopheles vectorial capacity metrics and malaria transmission factors within the Rimdamal II Study
No full text2021 Fall.Includes bibliographical references.To view the abstract, please see the full text of the document
