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1.
bioRxiv ; 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39229052

ABSTRACT

Climate warming is expected to shift the distributions of mosquitoes and mosquito-borne diseases, facilitating expansions at cool range edges and contractions at warm range edges. However, whether mosquito populations could maintain their warm edges through evolutionary adaptation remains unknown. Here, we investigate the potential for thermal adaptation in Aedes sierrensis, a congener of the major disease vector species that experiences large thermal gradients in its native range, by assaying tolerance to prolonged and acute heat exposure, and its genetic basis in a diverse, field-derived population. We found pervasive evidence of heritable genetic variation in acute heat tolerance, which phenotypically trades off with tolerance to prolonged heat exposure. A simple evolutionary model based on our data shows that the estimated maximum rate of evolutionary adaptation in mosquito heat tolerance typically exceeds that of projected climate warming under idealized conditions. Our findings indicate that natural mosquito populations may have the potential to track projected warming via genetic adaptation. Prior climate-based projections may thus underestimate the range of mosquito and mosquito-borne disease distributions under future climate conditions.

2.
Heredity (Edinb) ; 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39164520

ABSTRACT

A key goal of evolutionary genomics is to harness molecular data to draw inferences about selective forces that have acted on genomes. The field progresses in large part through the development of advanced molecular-evolution analysis methods. Here we explored the intersection between classical sequence-based tests for selection and an empirical expression-based approach, using stem cells from Mus musculus subspecies as a model. Using a test of directional, cis-regulatory evolution across genes in pathways, we discovered a unique program of induction of translation genes in stem cells of the Southeast Asian mouse M. m. castaneus relative to its sister taxa. We then mined population-genomic sequences to pursue underlying regulatory mechanisms for this expression divergence, finding robust evidence for alleles unique to M. m. castaneus at the upstream regions of the translation genes. We interpret our data under a model of changes in lineage-specific pressures across Mus musculus in stem cells with high translational capacity. Our findings underscore the rigor of integrating expression and sequence-based methods to generate hypotheses about evolutionary events from long ago.

3.
bioRxiv ; 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39149389

ABSTRACT

Next generation sequencing has unlocked a wealth of genotype information for microbial populations, but phenotyping remains a bottleneck for exploiting this information, particularly for pathogens that are difficult to manipulate. Here, we establish a method for high-throughput phenotyping of mixed cultures, in which the pattern of naturally occurring single-nucleotide polymorphisms in each isolate is used as intrinsic barcodes which can be read out by sequencing. We demonstrate that our method can correctly deconvolute strain proportions in simulated mixed-strain pools. As an experimental test of our method, we perform whole genome sequencing of 66 natural isolates of the thermally dimorphic pathogenic fungus Coccidioides posadasii and infer the strain compositions for large mixed pools of these strains after competition at 37°C and room temperature. We validate the results of these selection experiments by recapitulating the temperature-specific enrichment results in smaller pools. Additionally, we demonstrate that strain fitness estimated by our method can be used as a quantitative trait for genome-wide association studies. We anticipate that our method will be broadly applicable to natural populations of microbes and allow high-throughput phenotyping to match the rate of genomic data acquisition.

4.
J Breast Imaging ; 6(2): 166-174, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38412358

ABSTRACT

OBJECTIVE: Screening based on individual risk factors results in detection of earlier, more curable breast cancer. There is expectation that improved public education about the importance of personalized screening will result in earlier diagnoses and reduced breast cancer mortality. The purpose of this study is to evaluate the effectiveness of community education on patient perceptions about risk-based screening. METHODS: This study is Health Insurance Portability and Accountability Act-compliant and institutional review board exempt. A standardized curriculum was used by radiologists and experts to conduct nine 1-hour patient education sessions between October 2018 and January 2019 about breast cancer risk factors and screening options. Patient participants completed voluntary, anonymous pre-event and post event surveys to determine if the presented educational program led to attitude changes. Survey results were summarized using statistical analysis including mean, median, range, and percentage of participants responding and comparison of pre- and post event fear and anxiety. RESULTS: Of 336 education session participants, 59.5% (200/336) completed the pre-event and 44.3% (149/336) completed the post event surveys, Respondents reported decreased anxiety and fear regarding breast cancer screening following educational sessions, with 36.1% (64/178) reporting anxiety pre-event compared to 23.3% (31/133) post event, although the difference was not statistically significant (P = .96). Additionally, 64.7% (55/85) of participants stated they were more likely to schedule breast cancer screening based on individual risk factors, and 98.0% (145/148) of participants reported increased knowledge on post event surveys. CONCLUSION: This study demonstrates the importance and effectiveness of community-based educational programs in increasing knowledge of risk-based screening and potentially reducing anxiety related to screening.


Subject(s)
Breast Neoplasms , United States , Humans , Female , Breast Neoplasms/diagnosis , Early Detection of Cancer , Health Education , Curriculum , Surveys and Questionnaires
5.
Nat Commun ; 15(1): 467, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38212606

ABSTRACT

Dietary restriction (DR) delays aging, but the mechanism remains unclear. We identified polymorphisms in mtd, the fly homolog of OXR1, which influenced lifespan and mtd expression in response to DR. Knockdown in adulthood inhibited DR-mediated lifespan extension in female flies. We found that mtd/OXR1 expression declines with age and it interacts with the retromer, which regulates trafficking of proteins and lipids. Loss of mtd/OXR1 destabilized the retromer, causing improper protein trafficking and endolysosomal defects. Overexpression of retromer genes or pharmacological restabilization with R55 rescued lifespan and neurodegeneration in mtd-deficient flies and endolysosomal defects in fibroblasts from patients with lethal loss-of-function of OXR1 variants. Multi-omic analyses in flies and humans showed that decreased Mtd/OXR1 is associated with aging and neurological diseases. mtd/OXR1 overexpression rescued age-related visual decline and tauopathy in a fly model. Hence, OXR1 plays a conserved role in preserving retromer function and is critical for neuronal health and longevity.


Subject(s)
Aging , Nervous System Diseases , Humans , Female , Aging/genetics , Longevity/genetics , Neurons/metabolism , Nervous System Diseases/metabolism , Brain/metabolism , Caloric Restriction , Mitochondrial Proteins/metabolism
6.
FEMS Yeast Res ; 242024 01 09.
Article in English | MEDLINE | ID: mdl-38218591

ABSTRACT

Among molecular biologists, the group of fungi called Saccharomycotina is famous for its yeasts. These yeasts in turn are famous for what they have in common-genetic, biochemical, and cell-biological characteristics that serve as models for plants and animals. But behind the apparent homogeneity of Saccharomycotina species lie a wealth of differences. In this review, we discuss traits that vary across the Saccharomycotina subphylum. We describe cases of bright pigmentation; a zoo of cell shapes; metabolic specialties; and species with unique rules of gene regulation. We discuss the genetics of this diversity and why it matters, including insights into basic evolutionary principles with relevance across Eukarya.


Subject(s)
Ascomycota , Ascomycota/genetics , Biological Evolution , Yeasts/genetics , Phenotype
7.
bioRxiv ; 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-37503246

ABSTRACT

A key goal of evolutionary genomics is to harness molecular data to draw inferences about selective forces that have acted on genomes. The field progresses in large part through the development of advanced molecular-evolution analysis methods. Here we explored the intersection between classical sequence-based tests for selection and an empirical expression-based approach, using stem cells from Mus musculus subspecies as a model. Using a test of directional, cis-regulatory evolution across genes in pathways, we discovered a unique program of induction of translation genes in stem cells of the Southeast Asian mouse M. m. castaneus relative to its sister taxa. As a complement, we used sequence analyses to find population-genomic signatures of selection in M. m. castaneus, at the upstream regions of the translation genes, including at transcription factor binding sites. We interpret our data under a model of changes in lineage-specific pressures across Mus musculus in stem cells with high translational capacity. Together, our findings underscore the rigor of integrating expression and sequence-based methods to generate hypotheses about evolutionary events from long ago.

8.
AJR Am J Roentgenol ; 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37966035

ABSTRACT

Breast imaging studies are complex examinations for patients and providers. Breast imaging providers and organizations invest significant resources in educating patients and referring providers to address variability in changing breast cancer screening recommendations, cultural biases, and socioeconomic barriers for patients. The breast imaging examination frequently involves multiple imaging modalities including interventional procedures, thus requiring multiple room types. Practices need to consider variables that affect workflow efficiency throughout the process of scheduling, examination performance, interpretation, and results delivery, as well as options in facilities design to create inviting yet functional environments for patients. Breast imaging appointments provide opportunity to capture individual breast cancer risk and to engage patients in health education and breast screening awareness. This AJR Expert Panel Narrative Review discusses ways in which breast imaging facilities can optimize patient experience throughout the complex process of a breast imaging examination, based on the authors' observations and opinions that include private and academic breast imaging experience.

9.
bioRxiv ; 2023 Dec 04.
Article in English | MEDLINE | ID: mdl-37503266

ABSTRACT

Dietary restriction (DR) is a potent method to enhance lifespan and healthspan, but individual responses are influenced by genetic variations. Understanding how metabolism-related genetic differences impact longevity and healthspan are unclear. To investigate this, we used metabolites as markers to reveal how different genotypes respond to diet to influence longevity and healthspan traits. We analyzed data from Drosophila Genetic Reference Panel strains raised under AL and DR conditions, combining metabolomic, phenotypic, and genome-wide information. Employing two computational methods across species-random forest modeling within the DGRP and Mendelian randomization in the UK Biobank-we pinpointed key traits with cross-species relevance that influence lifespan and healthspan. Notably, orotate was linked to parental age at death in humans and counteracted DR effects in flies, while threonine extended lifespan, in a strain- and sex-specific manner. Thus, utilizing natural genetic variation data from flies and humans, we employed a systems biology approach to elucidate potential therapeutic pathways and metabolomic targets for diet-dependent changes in lifespan and healthspan.

10.
G3 (Bethesda) ; 13(7)2023 07 05.
Article in English | MEDLINE | ID: mdl-37097016

ABSTRACT

Cellular senescence is a program of cell cycle arrest, apoptosis resistance, and cytokine release induced by stress exposure in metazoan cells. Landmark studies in laboratory mice have characterized a number of master senescence regulators, including p16INK4a, p21, NF-κB, p53, and C/EBPß. To discover other molecular players in senescence, we developed a screening approach to harness the evolutionary divergence between mouse species. We found that primary cells from the Mediterranean mouse Mus spretus, when treated with DNA damage to induce senescence, produced less cytokine and had less-active lysosomes than cells from laboratory Mus musculus. We used allele-specific expression profiling to catalog senescence-dependent cis-regulatory variation between the species at thousands of genes. We then tested for correlation between these expression changes and interspecies sequence variants in the binding sites of transcription factors. Among the emergent candidate senescence regulators, we chose a little-studied cell cycle factor, upstream stimulatory factor 2 (USF2), for molecular validation. In acute irradiation experiments, cells lacking USF2 had compromised DNA damage repair and response. Longer-term senescent cultures without USF2 mounted an exaggerated senescence regulatory program-shutting down cell cycle and DNA repair pathways, and turning up cytokine expression, more avidly than wild-type. We interpret these findings under a model of pro-repair, anti-senescence regulatory function by USF2. Our study affords new insights into the mechanisms by which cells commit to senescence, and serves as a validated proof of concept for natural variation-based regulator screens.


Subject(s)
Cellular Senescence , DNA Damage , Animals , Mice , Cell Cycle , Cellular Senescence/genetics , Cytokines/metabolism , Tumor Suppressor Protein p53/genetics , Upstream Stimulatory Factors/genetics
11.
J Cancer Surviv ; 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37093518

ABSTRACT

PURPOSE: Toxicity is a significant problem among women receiving systemic chemotherapy for breast cancer, with up to 60% experiencing hematologic and 14% experiencing non-hematologic toxicity. Chemotherapy is dosed using body surface area, which does not account for heterogeneity in lean body mass (LBM) and adipose tissue (AT). This systematic review, registered with the PROSPERO International Prospective Register of Systematic Reviews (#CRD42021279874), evaluates associations between body composition and chemotherapy-related toxicity during breast cancer treatment. METHODS: Scientific literature databases (PubMed, Scopus, CINAHL, and CENTRAL) were systematically searched in November 2021 for studies evaluating associations between body composition (assessed using computed tomography or dual x-ray absorptiometry) and chemotherapy-related toxicity among women receiving breast cancer treatment. Eligibility was not limited by year or country of publication. Article screening and data abstraction was conducted using the Covidence Systematic Review Management System. Predetermined criteria were used to evaluate rigor of participant recruitment, representativeness of the population, and use of validated measures of body composition and toxicity. RESULTS: An inverse association between LBM and toxicity was reported in seven of the eight included studies, although definitions of low LBM differed across studies. Three studies evaluated the association between AT and chemotherapy toxicity with inconsistent findings. Heterogeneity in body composition measures/definitions and treatment regimens precluded the ability to perform meta-analyses. CONCLUSION: Low LBM appears to be a risk factor for chemotherapy toxicity, but the role of AT is unclear. IMPLICATIONS FOR CANCER SURVIVORS: Further research that accounts for guideline concordance in chemotherapy prescriptions and the use of supportive care medications is needed.

12.
Geroscience ; 45(2): 1237-1245, 2023 04.
Article in English | MEDLINE | ID: mdl-36018536

ABSTRACT

Lysosomes are crucial for degradation and recycling of damaged proteins and cellular components. Therapeutic strategies enhancing lysosomal function are a promising approach for aging and age-related neurodegenerative diseases. Here, we show that an FDA approved drug sodium polystyrene sulfonate (SPS), used to reduce high blood potassium in humans, enhances lysosomal function both in C. elegans and in human neuronal cells. Enhanced lysosomal function following SPS treatment is accompanied by the suppression of proteotoxicity caused by expression of the neurotoxic peptides Aß and TAU. Additionally, treatment with SPS imparts health benefits as it significantly increases lifespan in C. elegans. Overall our work supports the potential use of SPS as a prospective geroprotective intervention.


Subject(s)
Caenorhabditis elegans , Potassium , Animals , Humans , Potassium/metabolism , Prospective Studies , Lysosomes/metabolism
13.
bioRxiv ; 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38187519

ABSTRACT

In the search to understand how evolution builds new traits, ancient events are often the hardest to dissect. Species-unique traits pose a particular challenge for geneticists-cases in which a character arose long ago and, in the modern day, is conserved within a species, distinguishing it from reproductively isolated relatives. In this work, we have developed the budding yeast genus Kluyveromyces as a model for mechanistic dissection of trait variation across species boundaries. Phenotypic profiling revealed robust heat and chemical-stress tolerance phenotypes that distinguished the compost yeast K. marxianus from the rest of the clade. We used culture-based, transcriptomic, and genetic approaches to characterize the metabolic requirements of the K. marxianus trait syndrome. We then generated a population-genomic resource for K. marxianus and harnessed it in molecular-evolution analyses, which found hundreds of housekeeping genes with evidence for adaptive protein variation unique to this species. Our data support a model in which, in the distant past, K. marxianus underwent a vastly complex remodeling of its proteome to achieve stress resistance. Such a polygenic architecture, involving nucleotide-level allelic variation on a massive scale, is consistent with theoretical models of the mechanisms of long-term adaptation, and suggests principles of broad relevance for interspecies trait genetics.

14.
J Fungi (Basel) ; 8(12)2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36547568

ABSTRACT

The human fungal pathogen Coccidioides spp. causes valley fever, a treatment-refractory and sometimes deadly disease prevalent in arid regions of the western hemisphere. Fungal virulence in the mammalian host hinges on a switch between growth as hyphae and as large spherules containing infectious spores. How these virulence programs are encoded in the genome remains poorly understood. Drawing on Coccidioides genomic resources, we first discovered a new facet of genome organization in this system: spherule-gene islands, clusters of genes physically linked in the genome that exhibited specific mRNA induction in the spherule phase. Next, we surveyed copy-number variation genome-wide among strains of C. posadasii. Emerging from this catalog were spherule-gene islands with striking presence-absence differentiation between C. posadasii populations, a pattern expected from virulence factors subjected to different selective pressures across habitats. Finally, analyzing single-nucleotide differences across C. posadasii strains, we identified signatures of natural selection in spherule-expressed genes. Together, our data establish spherule-gene islands as candidate determinants of virulence and targets of selection in Coccidioides.

15.
BMC Genomics ; 23(1): 842, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36539699

ABSTRACT

BACKGROUND: Organisms in the wild can acquire disease- and stress-resistance traits that outstrip the programs endogenous to humans. Finding the molecular basis of such natural resistance characters is a key goal of evolutionary genetics. Standard statistical-genetic methods toward this end can perform poorly in organismal systems that lack high rates of meiotic recombination, like Caenorhabditis worms. RESULTS: Here we discovered unique ER stress resistance in a wild Kenyan C. elegans isolate, which in inter-strain crosses was passed by hermaphrodite mothers to hybrid offspring. We developed an unbiased version of the reciprocal hemizygosity test, RH-seq, to explore the genetics of this parent-of-origin-dependent phenotype. Among top-scoring gene candidates from a partial-coverage RH-seq screen, we focused on the neuronally-expressed, cuticlin-like gene cutl-24 for validation. In gene-disruption and controlled crossing experiments, we found that cutl-24 was required in Kenyan hermaphrodite mothers for ER stress tolerance in their inter-strain hybrid offspring; cutl-24 was also a contributor to the trait in purebred backgrounds. CONCLUSIONS: These data establish the Kenyan strain allele of cutl-24 as a determinant of a natural stress-resistant state, and they set a precedent for the dissection of natural trait diversity in invertebrate animals without the need for a panel of meiotic recombinants.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis , Humans , Animals , Caenorhabditis elegans/genetics , Kenya , Phenotype , Caenorhabditis elegans Proteins/genetics
17.
Geroscience ; 44(4): 2195-2211, 2022 08.
Article in English | MEDLINE | ID: mdl-35381951

ABSTRACT

Elevated serum urate (hyperuricemia) promotes crystalline monosodium urate tissue deposits and gout, with associated inflammation and increased mortality. To identify modifiers of uric acid pathologies, we performed a fly Genome-Wide Association Study (GWAS) on purine metabolites using the Drosophila Genetic Reference Panel strains. We tested the candidate genes using the Drosophila melanogaster model of hyperuricemia and uric acid crystallization ("concretion formation") in the kidney-like Malpighian tubule. Medusa (mda) activity increased urate levels and inflammatory response programming. Conversely, whole-body mda knockdown decreased purine synthesis precursor phosphoribosyl pyrophosphate, uric acid, and guanosine levels; limited formation of aggregated uric acid concretions; and was sufficient to rescue lifespan reduction in the fly hyperuricemia and gout model. Levels of mda homolog FAM214A were elevated in inflammatory M1- and reduced in anti-inflammatory M2-differentiated mouse bone marrow macrophages, and influenced intracellular uric acid levels in human HepG2 transformed hepatocytes. In conclusion, mda/FAM214A acts in a conserved manner to regulate purine metabolism, promotes disease driven by hyperuricemia and associated tissue inflammation, and provides a potential novel target for uric acid-driven pathologies.


Subject(s)
Drosophila Proteins , Gout , Hyperuricemia , Animals , Humans , Mice , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Genome-Wide Association Study , Gout/genetics , Gout/complications , Gout/metabolism , Hyperuricemia/genetics , Hyperuricemia/complications , Hyperuricemia/metabolism , Inflammation/genetics , Inflammation/complications , Purines/metabolism , Uric Acid/urine , Drosophila Proteins/genetics
18.
G3 (Bethesda) ; 12(4)2022 04 04.
Article in English | MEDLINE | ID: mdl-35137016

ABSTRACT

Coccidioidomycosis is a common fungal disease that is endemic to arid and semi-arid regions of both American continents. Coccidioides immitis and Coccidioides posadasii are the etiological agents of the disease, also known as Valley Fever. For several decades, the C. posadasii strain Silveira has been used widely in vaccine studies, is the source strain for production of diagnostic antigens, and is a widely used experimental strain for functional studies. In 2009, the genome was sequenced using Sanger sequencing technology, and a draft assembly and annotation were made available. In this study, the genome of the Silveira strain was sequenced using single molecule real-time sequencing PacBio technology, assembled into chromosomal-level contigs, genotyped, and the genome was reannotated using sophisticated and curated in silico tools. This high-quality genome sequencing effort has improved our understanding of chromosomal structure, gene set annotation, and lays the groundwork for identification of structural variants (e.g. transversions, translocations, and copy number variants), assessment of gene gain and loss, and comparison of transposable elements in future phylogenetic and population genomics studies.


Subject(s)
Coccidioides , Coccidioidomycosis , Base Sequence , Coccidioides/genetics , Coccidioidomycosis/diagnosis , Coccidioidomycosis/epidemiology , Coccidioidomycosis/genetics , Humans , Phylogeny
19.
Article in English | MEDLINE | ID: mdl-36911365

ABSTRACT

Many traits of industrial and basic biological interest arose long ago, and manifest now as fixed differences between a focal species and its reproductively isolated relatives. In these systems, extant individuals can hold clues to the mechanisms by which phenotypes evolved in their ancestors. We harnessed yeast thermotolerance as a test case for such molecular-genetic inferences. In viability experiments, we showed that extant Saccharomyces cerevisiae survived at temperatures where cultures of its sister species S. paradoxus died out. Then, focusing on loci that contribute to this difference, we found that the genetic mechanisms of high-temperature growth changed with temperature. We also uncovered an enrichment of low-frequency variants at thermotolerance loci in S. cerevisiae population sequences, suggestive of a history of non-neutral selective forces acting at these genes. We interpret these results in light of models of the evolutionary mechanisms by which the thermotolerance trait arose in the S. cerevisiae lineage. Together, our results and interpretation underscore the power of genetic approaches to explore how an ancient trait came to be.

20.
G3 (Bethesda) ; 12(2)2022 02 04.
Article in English | MEDLINE | ID: mdl-34878132

ABSTRACT

Decades of successes in statistical genetics have revealed the molecular underpinnings of traits as they vary across individuals of a given species. But standard methods in the field cannot be applied to divergences between reproductively isolated taxa. Genome-wide reciprocal hemizygosity mapping (RH-seq), a mutagenesis screen in an interspecies hybrid background, holds promise as a method to accelerate the progress of interspecies genetics research. Here, we describe an improvement to RH-seq in which mutants harbor barcodes for cheap and straightforward sequencing after selection in a condition of interest. As a proof of concept for the new tool, we carried out genetic dissection of the difference in thermotolerance between two reproductively isolated budding yeast species. Experimental screening identified dozens of candidate loci at which variation between the species contributed to the thermotolerance trait. Hits were enriched for mitosis genes and other housekeeping factors, and among them were multiple loci with robust sequence signatures of positive selection. Together, these results shed new light on the mechanisms by which evolution solved the problems of cell survival and division at high temperature in the yeast clade, and they illustrate the power of the barcoded RH-seq approach.


Subject(s)
Thermotolerance , Chromosome Mapping/methods , Genome-Wide Association Study/methods , Humans , Phenotype , Saccharomyces cerevisiae/genetics , Thermotolerance/genetics
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