Biology subjects

Hale, J. J.

Publications and source records attributed to Hale, J. J..

4 recordsLinked to original sources

bioRxiv2026

Defining the Candidozyma auris pan-genome and essentiality

Candidozyma auris is a multi-drug resistant fungal pathogen that causes hospital outbreaks, but genetic variation and gene function in this organism remain undercharacterized. Here, we performed pangenome analysis on 695 genetically representative isolates of C. auris and found that only 2.6% of gene families varied in their presence, mainly consisting of gene loss events or clade-specific genes, highlighting the clonal nature of these strains. Using microbial genome-wide association, we identified two loci associated with altered keratinocyte adherence, including genes with unknown function. To look broadly at gene function, we developed a genome-scale insertional mutagenesis approach and identified 614 high-confidence essential genes. Nearly one-third of these genes exhibited divergent essentiality compared to the model yeasts Candida albicans and Saccharomyces cerevisiae. Together, this study highlights organism-specific biology and provides a comprehensive resource for identifying species-specific determinants of virulence and targets for antifungal drug development.

microbiology↗

bioRxiv2025

Global epistasis in budding yeast driven by many natural variants whose effects scale with fitness

Global epistasis is a phenomenon in which the effects of genetic perturbations depend on the fitness of the individuals in which they occur. In populations with natural genetic variation, global epistasis arises from interactions between perturbations and polymorphic loci that are mediated by fitness. To investigate the prevalence and characteristics of loci involved in these interactions in the budding yeast Saccharomyces cerevisiae, we used combinatorial DNA barcode sequencing to measure the fitness of 169 cross progeny (segregants) subjected to 8,126 CRISPRi perturbations across two environments. Global epistasis was evident in these data, with more fit segregants within each environment exhibiting greater sensitivity to genetic perturbations than less fit segregants. We dissected the genetic basis of this global epistasis by scanning the genome for loci whose effects covary with CRISPRi-induced reductions in population fitness. This approach identified 58 loci that interact with fitness, most of which exhibited larger effects in the absence of genetic perturbations. In aggregate, these loci explained the observed global epistasis in each environment and demonstrated that the loci contributing to global epistasis largely overlap with those influencing fitness in unperturbed conditions.

genetics↗

bioRxiv2023

Deep Learning-based structural and functional annotation of Pandoravirus hypothetical proteins

Giant viruses, including Pandoraviruses, contain large amounts of genomic dark matter - genes encoding proteins of unknown function. New generation, deep learning-based protein structure modelling offers new opportunities to apply structure-based function inference to these sequences, often labelled as hypothetical proteins. However, the AlphaFold Protein Structure Database, a convenient resource covering the majority of UniProt, currently lacks models for most viral proteins. Here, we apply a panoply of predictive methods to protein structure predictions representative of large clusters of hypothetical proteins shared among four Pandoraviruses. In several cases, strong functional predictions can be made. Thus, we identify a likely nucleotidyltransferase putatively involved in viral tRNA maturation that has a BTB domain presumably involved in protein-protein interactions. We further identify a cluster of membrane channel sequences presenting three paralogous families which may, as seen in other giant viruses, induce host cell membrane depolarization. And we identify homologues of calcium-activated potassium channel beta subunits and pinpoint their likely Acanthamoeba cellular alpha subunit counterparts. Despite these successes, many other clusters remain cryptic, having folds that are either too functionally promiscuous or too novel to provide strong clues as to their role. These results suggest that significant structural and functional novelty remains to be uncovered in the giant virus proteomes.

bioinformatics↗

bioRxiv2023

Genome-scale analysis of interactions between genetic perturbations and natural variation

Interactions between genetic perturbations and segregating loci can cause perturbations to show different phenotypic effects across genetically distinct individuals. To study these interactions on a genome scale in many individuals, we used combinatorial DNA barcode sequencing to measure the fitness effects of 7,700 CRISPRi perturbations targeting 1,712 distinct genes in 169 yeast cross progeny (or segregants). We identified 460 genes whose perturbation has different effects across segregants. Several factors caused perturbations to show variable effects, including baseline segregant fitness, the mean effect of a perturbation across segregants, and interacting loci. We mapped 234 interacting loci and found four hub loci that interact with many different perturbations. Perturbations that interact with a given hub exhibit similar epistatic relationships with the hub and show enrichment for cellular processes that may mediate these interactions. These results suggest that an individuals response to perturbations is shaped by a network of perturbation-locus interactions that cannot be measured by approaches that examine perturbations or natural variation alone.

genetics↗