Publications by authors named "Timothy Y James"

Article Synopsis
  • Reproductive barriers among sister species of the fungus Trichaptum abietinum are stronger where their populations overlap, suggesting that selection may be promoting these barriers to prevent hybridization.
  • Genetic analysis reveals six main groups of T. abietinum located in Asia, Europe, and North America, with North American groups showing reproductive isolation while European groups can interbreed.
  • The research highlights a correlation between genomic divergence and reproductive barriers, along with the potential role of specific genes in hybrid sterility, indicating that T. abietinum is a valuable model for studying how species evolve separately and maintain reproductive differences.
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Article Synopsis
  • * A study of 69 R. arrhizus strains showed that most had similar metabolic profiles, but 13 strains exhibited unique behaviors, indicating some niche differentiation among them.
  • * The research found that R. arrhizus has significant metabolic diversity, favoring alcohols and highlighting specific substrates that can promote sporulation, which could be useful for enhancing industrial processes.
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A case-control study of sporadic amyotrophic lateral sclerosis (ALS) in a mountainous village in the French Alps discovered an association of cases with a history of eating wild fungi (false morels) collected locally and initially identified and erroneously reported as . Specialist re-examination of dried specimens of the ALS-associated fungi demonstrated they were members of the group, namely , species that have been reported to contain substantially higher concentrations of gyromitrin than present in . Gyromitrin is metabolized to monomethylhydrazine, which is responsible not only for the acute oral toxic and neurotoxic properties of false morels but also has genotoxic potential with proposed mechanistic relevance to the etiology of neurodegenerative disease.

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Unlabelled: The impacts of microsporidia on host individuals are frequently subtle and can be context dependent. A key example of the latter comes from a recently discovered microsporidian symbiont of , the net impact of which was found to shift from negative to positive based on environmental context. Given this, we hypothesized low baseline virulence of the microsporidian; here, we investigated the impact of infection on hosts in controlled conditions and the absence of other stressors.

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The global panzootic lineage (GPL) of the pathogenic fungus Batrachochytrium dendrobatidis (Bd) has caused severe amphibian population declines, yet the drivers underlying the high frequency of GPL in regions of amphibian decline are unclear. Using publicly available Bd genome sequences, we identified multiple non-GPL Bd isolates that contain a circular Rep-encoding single-stranded (CRESS)-like DNA virus, which we named Bd DNA virus 1 (BdDV-1). We further sequenced and constructed genome assemblies with long read sequences to find that the virus is integrated into the nuclear genome in some strains.

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Generalist pathogens maintain infectivity in numerous hosts; how this broad ecological niche impacts host-pathogen coevolution remains to be widely explored. Batrachochytrium dendrobatidis (Bd) is a highly generalist pathogenic fungus that has caused devastating declines in hundreds of amphibian species worldwide. This review examines amphibian chytridiomycosis host-pathogen interactions and available evidence for coevolution between Bd and its numerous hosts.

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Fungi that are edible or fermentative were domesticated through selective cultivation of their desired traits. Domestication is often associated with inbreeding or selfing, which may fix traits other than those under selection, and causes an overall decrease in heterozygosity. A hallucinogenic mushroom, Psilocybe cubensis, was domesticated from its niche in livestock dung for production of psilocybin.

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Model organisms are crucial in research as they can provide key insights applicable to other species. This study proposes the use of the amphibian species , widely available through the aquarium trade, as a model organism for the study of chytridiomycosis, a disease caused by the fungus (Bd) and linked to amphibian decline and extinction globally. Currently, no model organisms are used in the study of chytridiomycosis, particularly because of the lack of availability and nonstandardized methods.

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What are the implications of misunderstanding sex as a binary, and why is it essential for scientists to incorporate a more expansive view of biological sex in our teaching and research? This roundtable will include many of our symposium speakers, including biologists and intersex advocates, to discuss these topics and visibilize the link between ongoing reification of dyadic sex within scientific communities and the social, political, and medical oppression faced by queer, transgender, and especially intersex communities. As with the symposium as a whole, this conversation is designed to bring together empirical research and implementation of equity, inclusion, and justice principles, which are often siloed into separate rooms and conversations at academic conferences. Given the local and national attacks on the rights of intersex individuals and access to medical care and bodily autonomy, this interdisciplinary discussion is both timely and urgent.

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The first genome sequenced of a eukaryotic organism was for , as reported in 1996, but it was more than 10 years before any of the zygomycete fungi, which are the early-diverging terrestrial fungi currently placed in the phyla and , were sequenced. The genome for was completed in 2008; currently, more than 1000 zygomycete genomes have been sequenced. Genomic data from these early-diverging terrestrial fungi revealed deep phylogenetic separation of the two major clades-primarily plant-associated saprotrophic and mycorrhizal versus the primarily mycoparasitic or animal-associated parasites and commensals in the .

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Environmental DNA analyses of fungal communities typically reveal a much larger diversity than can be ascribed to known species. Much of this hidden diversity lies within undescribed fungal lineages, especially the early diverging fungi (EDF). Although these EDF often represent new lineages even at the phylum level, they have never been cultured, making their morphology and ecology uncertain.

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Eukaryotes have evolved myriad ways of uniting gametes during sexual reproduction. A repeated pattern is the convergent evolution of a mating system with the fusion of larger gametes with smaller gametes (anisogamy) from that of fusion between morphologically identical gametes (isogamy). In anisogamous species, sexes are defined as individuals that produce only one gamete type.

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Candida albicans is a frequent colonizer of human mucosal surfaces as well as an opportunistic pathogen. C. albicans is remarkably versatile in its ability to colonize diverse host sites with differences in oxygen and nutrient availability, pH, immune responses, and resident microbes, among other cues.

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Knowledge of breeding systems and genetic diversity is critical to select and combine desired traits that advance new cultivars in agriculture and horticulture. Mushrooms that produce psilocybin, magic mushrooms, may potentially be used in therapeutic and wellness industries, and stand to benefit from genetic improvement. We studied haploid siblings of Psilocybe subaeruginosa to resolve the genetics behind mating compatibility and advance knowledge of breeding.

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Gyromitrin (acetaldehyde -methyl--formylhydrazone) and its homologs are deadly mycotoxins produced most infamously by the lorchel (also known as false morel) , which is paradoxically consumed as a delicacy in some parts of the world. There is much speculation about the presence of gyromitrin in other species of the lorchel family (Discinaceae), but no studies have broadly assessed its distribution. Given the history of poisonings associated with the consumption of and , we hypothesized that gyromitrin evolved in the last common ancestor of these taxa and would be present in their descendants with adaptive loss of function in the nested truffle clade, .

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The fungal kingdom represents an extraordinary diversity of organisms with profound impacts across animal, plant, and ecosystem health. Fungi simultaneously support life, by forming beneficial symbioses with plants and producing life-saving medicines, and bring death, by causing devastating diseases in humans, plants, and animals. With climate change, increased antimicrobial resistance, global trade, environmental degradation, and novel viruses altering the impact of fungi on health and disease, developing new approaches is now more crucial than ever to combat the threats posed by fungi and to harness their extraordinary potential for applications in human health, food supply, and environmental remediation.

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Most of the described species in kingdom Fungi are contained in two phyla, the Ascomycota and the Basidiomycota (subkingdom Dikarya). As a result, our understanding of the biology of the kingdom is heavily influenced by traits observed in Dikarya, such as aerial spore dispersal and life cycles dominated by mitosis of haploid nuclei. We now appreciate that Fungi comprises numerous phylum-level lineages in addition to those of Dikarya, but the phylogeny and genetic characteristics of most of these lineages are poorly understood due to limited genome sampling.

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Glutamine synthetase (GlnS) is a key enzyme in nitrogen metabolism. We investigated the effect of the GlnS inhibitor glufosinate on the infection of by the blastocladialean fungus , assuming that interfering with the host nitrogen metabolism will affect the success of the parasite. Complete inhibition of infection, which could be bypassed by the GlnS product glutamine, was observed at millimolar concentrations of glufosinate.

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Sexual reproduction, mutation, and reassortment of nuclei increase genotypic diversity in rust fungi. Sexual reproduction is inherent to rust fungi, coupled with their coevolved plant hosts in native pathosystems. Rust fungi are hypothesised to exchange nuclei by somatic hybridisation with an outcome of increased genotypic diversity, independent of sexual reproduction.

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Balancing selection, an evolutionary force that retains genetic diversity, has been detected in multiple genes and organisms, such as the sexual mating loci in fungi. However, to quantify the strength of balancing selection and define the mating-related genes require a large number of strains. In tetrapolar basidiomycete fungi, sexual type is determined by two unlinked loci, MATA and MATB.

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Viruses infect virtually all forms of cellular life, and fungi are no exception. Knowledge regarding the diverse fungal viruses, or mycoviruses, including their genome structures, host ranges, and phenotypic effects, is growing at a fast pace. Mycovirus research has been stimulated by the idea that they could be an effective tool for biocontrol of fungal pathogens.

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Habitat fragmentation and infectious diseases threaten wildlife globally, but the interactions of these threats are poorly understood. For instance, while habitat fragmentation can impact genetic diversity at neutral loci, the impacts on disease-relevant loci are less well-studied. We examined the effects of habitat fragmentation in Brazil's Atlantic Forest on amphibian genetic diversity at an immune locus related to antigen presentation and detection (MHC IIB Exon 2).

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We describe environmental microbial eukaryotes (EMEs) sample collection, single-cell isolation, lysis, and genome amplification, followed by the rDNA amplification and OTU screening for recovery of high-quality species-specific genomes for assembly. These protocols are part of our pipeline that also includes bioinformatic methods. The pipeline and its application on a wide range of phyla of different sample complexity are described in our complementary paper.

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Cryptococcus neoformans × deneoformans hybrids (also known as serotype AD hybrids) are basidiomycete yeasts that are common in a clinical setting. Like many hybrids, the AD hybrids are largely locked at the F1 stage and are mostly unable to undergo normal meiotic reproduction. However, these F1 hybrids, which display a high (∼10%) sequence divergence are known to genetically diversify through mitotic recombination and aneuploidy, and this diversification may be adaptive.

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The increasing number of new fungal species described from all over the world along with the use of genetics to define taxa, has dramatically changed the classification system of early-diverging fungi over the past several decades. The number of phyla established for non-Dikarya fungi has increased from 2 to 17. However, to date, both the classification and phylogeny of the basal fungi are still unresolved.

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