Publications by authors named "Christopher Daum"

Temperature stress is one of the major limiting environmental factors that negatively impact global crop yields. is an obligate crassulacean acid metabolism (CAM) plant species, exhibiting much higher water-use efficiency and tolerance to drought and heat stresses than C or C plant species. Previous studies on gene expression responses to low- or high-temperature stress have been focused on C and C plants.

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Ancient whole-genome duplications are believed to facilitate novelty and adaptation by providing the raw fuel for new genes. However, it is unclear how recent whole-genome duplications may contribute to evolvability within recent polyploids. Hybridization accompanying some whole-genome duplications may combine divergent gene content among diploid species.

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Phyllosticta citricarpa is an important citrus-pathogen and a quarantine organism in the European Union. Its recently described relative, P. paracitricarpa, is very closely related and not listed as a quarantine organism.

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Fungal fermentation of food and agricultural by-products holds promise for improving food sustainability and security. However, the molecular basis of fungal waste-to-food upcycling remains poorly understood. Here we use a multi-omics approach to characterize oncom, a fermented food traditionally produced from soymilk by-products in Java, Indonesia.

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Anaerobic fungi produce biomass-degrading enzymes and natural products that are important to harness for several biotechnology applications. Although progress has been made in the development of methods for extracting nucleic acids for genomic and transcriptomic sequencing of these fungi, most studies are limited in that they do not sample multiple fungal growth phases in batch culture. In this study, we establish a method to harvest RNA from fungal monocultures and fungal-methanogen co-cultures, and also determine an optimal time frame for high-quality RNA extraction from anaerobic fungi.

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Gene functional descriptions offer a crucial line of evidence for candidate genes underlying trait variation. Conversely, plant responses to environmental cues represent important resources to decipher gene function and subsequently provide molecular targets for plant improvement through gene editing. However, biological roles of large proportions of genes across the plant phylogeny are poorly annotated.

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Plant establishment requires the formation and development of an extensive root system with architecture modulated by complex genetic networks. Here, we report the identification of the PtrXB38 gene as an expression quantitative trait loci (eQTL) hotspot, mapped using 390 leaf and 444 xylem Populus trichocarpa transcriptomes. Among predicted targets of this trans-eQTL were genes involved in plant hormone responses and root development.

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Article Synopsis
  • The order of rust fungi includes over 7,000 species that significantly affect agriculture, horticulture, forestry, and ecosystems.
  • Phakopsora pachyrhizi, the fungus responsible for Asian soybean rust disease, is a prime example of this impact and has a complex genome that has been challenging to assemble accurately.
  • Researchers sequenced three genomes of P. pachyrhizi, revealing a size of up to 1.25 Gb and a high transposable element content (~93%), demonstrating the role of these elements in host adaptation, stress responses, and genetic variability.
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Human activity impacts the evolutionary trajectories of many species worldwide. Global trade of agricultural goods contributes to the dispersal of pathogens reshaping their genetic makeup and providing opportunities for virulence gains. Understanding how pathogens surmount control strategies and cope with new climates is crucial to predicting the future impact of crop pathogens.

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In the North-Central United States, lowland ecotype switchgrass can increase yield by up to 50% compared with locally adapted but early flowering cultivars. However, lowland ecotypes are not winter tolerant. The mechanism for winter damage is unknown but previously has been associated with late flowering time.

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A number of crop wild relatives can tolerate extreme stress to a degree outside the range observed in their domesticated relatives. However, it is unclear whether or how the molecular mechanisms employed by these species can be translated to domesticated crops. Paspalum (Paspalum vaginatum) is a self-incompatible and multiply stress-tolerant wild relative of maize and sorghum.

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Fine-scale meiotic recombination is fundamental to the outcome of natural and artificial selection. Here, dense genetic mapping and haplotype reconstruction were used to estimate recombination for a full factorial Populus trichocarpa cross of 7 males and 7 females. Genomes of the resulting 49 full-sib families (N = 829 offspring) were resequenced, and high-fidelity biallelic SNP/INDELs and pedigree information were used to ascertain allelic phase and impute progeny genotypes to recover gametic haplotypes.

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Article Synopsis
  • CAM plants like Kalanchoë fedtschenkoi can tolerate drought and heat better than C3 and C4 plants due to a unique stomatal behavior that operates differently day and night.
  • A study investigated how this obligate CAM species responds at the genetic level to drought by analyzing leaf samples during different times of the day under varying drought conditions.
  • The findings indicated that drought stress did not significantly regulate CAM-related genes in K. fedtschenkoi; however, both CAM and C species showed similar transcriptional changes in key biological processes such as ABA signaling when under drought stress.
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We aimed to identify genomic traits of transitions to ectomycorrhizal ecology within the Boletales by comparing the genomes of 21 symbiotrophic species with their saprotrophic brown-rot relatives. Gene duplication rate is constant along the backbone of Boletales phylogeny with large loss events in several lineages, while gene family expansion sharply increased in the late Miocene, mostly in the Boletaceae. Ectomycorrhizal Boletales have a reduced set of plant cell-wall-degrading enzymes (PCWDEs) compared with their brown-rot relatives.

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Wood extractives, solvent-soluble fractions of woody biomass, are considered to be a factor impeding or excluding fungal colonization on the freshly harvested conifers. Among wood decay fungi, the basidiomycete Phlebiopsis gigantea has evolved a unique enzyme system to efficiently transform or degrade conifer extractives but little is known about the mechanism(s). In this study, to clarify the mechanism(s) of softwood degradation, we examined the transcriptome, proteome, and metabolome of P.

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Article Synopsis
  • * A new genome sequence related to Brassiceae helped confirm the hybridization model, revealing a significant time gap between the initial hybridizations and notable gene losses, particularly before the addition of the third subgenome.
  • * The analysis showed that each of the three subgenomes displays unique rates of gene loss but functions together seamlessly, suggesting a "mix and match" model where subgenome origin influences gene retention without affecting overall functionality.
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Microalgae efficiently convert sunlight into lipids and carbohydrates, offering bio-based alternatives for energy and chemical production. Improving algal productivity and robustness against abiotic stress requires a systems level characterization enabled by functional genomics. Here, we characterize a halotolerant microalga Scenedesmus sp.

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Article Synopsis
  • Long-term climate change threatens food and fuel security, and understanding the genetic basis of crop resilience is essential for improving productivity.
  • The genome assembly of switchgrass reveals insights into its climate adaptation capabilities, demonstrated through a study of diverse genotypes across various environments.
  • The findings suggest that gene flow and the polyploid structure of switchgrass enhance its adaptive potential, offering valuable resources for breeders aiming to boost bioenergy yield sustainably.
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Background: Currently, much is unknown about the taxonomic diversity and the mechanisms of methane metabolism in the Florida Everglades ecosystem. The Loxahatchee National Wildlife Refuge is a section of the Florida Everglades that is almost entirely unstudied in regard to taxonomic profiling. This short report analyzes the metagenome of soil samples from this Refuge to investigate the predominant taxa, as well as the abundance of genes involved in environmentally significant metabolic pathways related to methane production (nitrogen fixation and dissimilatory sulfite reduction).

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Metagenomic sequence data from defined mock communities is crucial for the assessment of sequencing platform performance and downstream analyses, including assembly, binning and taxonomic assignment. We report a comparison of shotgun metagenome sequencing and assembly metrics of a defined microbial mock community using the Oxford Nanopore Technologies (ONT) MinION, PacBio and Illumina sequencing platforms. Our synthetic microbial community BMock12 consists of 12 bacterial strains with genome sizes spanning 3.

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Physcomitrella patens is a bryophyte model plant that is often used to study plant evolution and development. Its resources are of great importance for comparative genomics and evo-devo approaches. However, expression data from Physcomitrella patens were so far generated using different gene annotation versions and three different platforms: CombiMatrix and NimbleGen expression microarrays and RNA sequencing.

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We report reference-quality genome assemblies and annotations for two accessions of soybean (Glycine max) and for one accession of Glycine soja, the closest wild relative of G. max. The G.

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Conventional wisdom holds that PCR amplification for sequencing should employ pooled replicate reactions to reduce bias due to jackpot effects and chimera formation. However, modern amplicon data analysis employs methods that may be less sensitive to such artifacts. Here we directly compare results from single versus triplicate reactions for 16S amplicon sequencing and find no significant impact of adopting a less labor-intensive single-reaction protocol.

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Article Synopsis
  • Strategies for sequencing fungal genomes depend on genome characteristics, DNA quality, and cost.
  • Illumina's sequencing by synthesis (SBS) offers fast, cost-effective short reads (~300 bp) but struggles with repetitive areas, while PacBio's single molecule, real-time (SMRT) sequencing provides longer reads (~12,500 bp) that help with complex genomes, albeit at a higher cost.
  • Illumina can work with lower quality DNA, whereas PacBio needs intact, long DNA fragments for optimal data quality.
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N6-methyldeoxyadenine (6mA) is a noncanonical DNA base modification present at low levels in plant and animal genomes, but its prevalence and association with genome function in other eukaryotic lineages remains poorly understood. Here we report that abundant 6mA is associated with transcriptionally active genes in early-diverging fungal lineages. Using single-molecule long-read sequencing of 16 diverse fungal genomes, we observed that up to 2.

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