Sex-specific regulation of gene expression is the most plausible way for generating sexually differentiated phenotypes from an essentially shared genome. However, since genetic material is shared, sex-specific selection in one sex can have an indirect response in the other sex. From a gene expression perspective, this tethered response can move one sex away from their wild-type expression state and potentially impact many gene regulatory networks.
View Article and Find Full Text PDFWith within-species genetic diversity estimates that span the gambit of that seen across the entirety of animals, the genus of nematodes holds unique potential to provide insights into how population size and reproductive strategies influence gene and genome organization and evolution. Our study focuses on , currently known as one of the most genetically diverse nematodes within its genus and metazoan phyla. Here, we present a high-quality gapless genome assembly and annotation for , revealing a common nematode chromosome arrangement characterized by gene-dense central regions and repeat rich peripheral parts.
View Article and Find Full Text PDFBody size is a fundamental trait that drives multiple evolutionary and ecological patterns. Caenorhabditis inopinata is a fig-associated nematode that is exceptionally large relative to other members of the genus, including Caenorhabditis elegans. We previously showed that C.
View Article and Find Full Text PDFThe evolution of reproductive mode is expected to have profound impacts on the genetic composition of populations. At the same time, ecological interactions can generate close associations among species, which can in turn generate a high degree of overlap in their spatial distributions. Caenorhabditis elegans is a hermaphroditic nematode that has enabled extensive advances in developmental genetics.
View Article and Find Full Text PDFMany trees exhibit masting - where reproduction is temporally variable and synchronous over large areas. Several dominant masting species occur in tropical cyclone (TC)-prone regions, but it is unknown whether TCs correlate with mast seeding. We analyzed long-term data (1958-2022) to test the hypothesis that TCs influence cone production in longleaf pine (Pinus palustris).
View Article and Find Full Text PDFBody size is a fundamental trait that drives multiple evolutionary and ecological patterns. is a fig-associated nematode that is exceptionally large relative to other members of the genus, including . We previously showed that is large primarily due to postembryonic cell size expansion that occurs during the larval-to-adult transition.
View Article and Find Full Text PDFThe floras on chemically and physically challenging soils, such as gypsum, shale, and serpentine, are characterized by narrowly endemic species. The evolution of edaphic endemics may be facilitated or constrained by genetic correlations among traits contributing to adaptation and reproductive isolation across soil boundaries. The yellow monkeyflowers in the Mimulus guttatus species complex are an ideal system in which to examine these evolutionary patterns.
View Article and Find Full Text PDFIn recent decades, genome-wide association studies (GWAS) have been the major approach to understand the biological basis of individual differences in traits and diseases. However, GWAS approaches have proven to have limited predictive power to explain individual differences, particularly for complex traits and diseases in which environmental factors play a substantial role in their etiology. Indeed, individual differences persist even in genetically identical individuals, although fully separating genetic and environmental causation is difficult or impossible in most organisms.
View Article and Find Full Text PDFSex-specific regulation of gene expression is the most plausible way for generating sexually differentiated phenotypes from an essentially shared genome. However, since genetic material is shared, sex-specific selection in one sex can have an indirect response in the other sex. From a gene expression perspective, this tethered response can move one sex away from their wildtype expression state and impact potentially many gene regulatory networks.
View Article and Find Full Text PDFCaenorhabditis nematodes form an excellent model for studying how the mode of reproduction affects genetic diversity, as some species reproduce via outcrossing whereas others can self-fertilize. Currently, chromosome-level patterns of diversity and recombination are only available for self-reproducing Caenorhabditis, making the generality of genomic patterns across the genus unclear given the profound potential influence of reproductive mode. Here we present a whole-genome diversity landscape, coupled with a new genetic map, for the outcrossing nematode C.
View Article and Find Full Text PDFEnviron Sci Technol
February 2023
Municipal wastewater collection and treatment systems are critical infrastructures, and they are also identified as major sources of anthropogenic CH emissions that contribute to climate change. The actual CH emissions at the plant- or regional level vary greatly due to site-specific conditions as well as high seasonal and diurnal variations. Here, we conducted the first quantitative analysis of CH emissions from different types of sewers and water resource recovery facilities (WRRFs).
View Article and Find Full Text PDFBackground: Temperature-controlled radiofrequency neurolysis of the posterior nasal nerve has been shown to reduce the symptom burden of patients with chronic rhinitis.
Objectives: To evaluate the long-term safety and effectiveness of temperature-controlled radiofrequency neurolysis of the posterior nasal nerve for the treatment of chronic rhinitis.
Methods: A prospective extension of a 12-month single-arm study, where reflective total nasal symptom score (rTNSS) and the responses to a study-specific quality of life questionnaire and patient satisfaction survey were collected at 24 months.
Significant gaps remain in understanding the response of plant reproduction to environmental change. This is partly because measuring reproduction in long-lived plants requires direct observation over many years and such datasets have rarely been made publicly available. Here we introduce MASTREE+, a data set that collates reproductive time-series data from across the globe and makes these data freely available to the community.
View Article and Find Full Text PDFSexual reproduction is a complex process that contributes to differences between the sexes and divergence between species. From a male's perspective, sexual selection can optimize reproductive success by acting on the variance in mating success (pre-insemination selection) as well as the variance in fertilization success (post-insemination selection). The balance between pre- and post-insemination selection has not yet been investigated using a strong hypothesis-testing framework that directly quantifies the effects of post-insemination selection on the evolution of reproductive success.
View Article and Find Full Text PDFThe Intervention Testing Program (CITP) was founded on the principle that compounds with positive effects across a genetically diverse test-set should have an increased probability of engaging conserved biochemical pathways with mammalian translational potential. To fulfill its mandate, the CITP uses a genetic diversity panel of strains for assaying longevity effects of candidate compounds. The panel comprises 22 strains from three different species, collected globally, to achieve inter-population genetic diversity.
View Article and Find Full Text PDFThe deleterious effects of inbreeding have been of extreme importance to evolutionary biology, but it has been difficult to characterize the complex interactions between genetic constraints and selection that lead to fitness loss and recovery after inbreeding. Haploid organisms and selfing organisms like the nematode Caenorhabditis elegans are capable of rapid recovery from the fixation of novel deleterious mutation; however, the potential for recovery and genomic consequences of inbreeding in diploid, outcrossing organisms are not well understood. We sought to answer two questions: 1) Can a diploid, outcrossing population recover from inbreeding via standing genetic variation and new mutation? and 2) How does allelic diversity change during recovery? We inbred C.
View Article and Find Full Text PDFBackground: Chronic rhinitis is a prevalent condition with a significant impact on quality of life. Posterior nasal nerve and vidian neurectomy are surgical options for treating the symptoms of chronic rhinitis but are invasive procedures.
Objective: To determine the outcomes of patients diagnosed with refractory chronic rhinitis and treated with temperature-controlled radiofrequency neurolysis of the posterior nasal nerve area in a minimally invasive procedure.
Ecological divergence is a fundamental source of phenotypic diversity between closely related species, yet the genetic architecture of most ecologically relevant traits is poorly understood. Differences in elevation can impose substantial divergent selection on both complex, correlated suites of traits (such as life-history), as well as novel adaptations. We use the species complex to assess if the divergence in elevation is accompanied by trait divergence in a group of closely related perennials and determine the genetic architecture of this divergence.
View Article and Find Full Text PDFEnvironmental variation along an elevational gradient can yield phenotypic differentiation resulting from varying selection pressures on plant traits related to seasonal responses. Thus, genetic clines can evolve in a suite of traits, including the circadian clock, that drives daily cycling in varied traits and that shares its genetic background with adaptation to seasonality. We used populations of annual from different elevations in the Sierra Nevada in California to explore among-population differentiation in the circadian clock, flowering responses to photoperiod, and phenological traits (days to cotyledon emergence, days to flowering, and days to seed ripening) in controlled common-garden conditions.
View Article and Find Full Text PDFThe double fertilization of the female gametophyte initiates embryogenesis and endosperm development in seeds the activation of genes involved in cell differentiation, organ patterning, and growth. A subset of genes expressed in endosperm exhibit imprinted expression, and the correct balance of gene expression between parental alleles is critical for proper endosperm and seed development. We use a transcriptional time series analysis to identify genes that are associated with key shifts in seed development, including genes associated with secondary cell wall synthesis, mitotic cell cycle, chromatin organization, auxin synthesis, fatty acid metabolism, and seed maturation.
View Article and Find Full Text PDFThe nematode is one of the key model systems in biology, including possessing the first fully assembled animal genome. Whereas is a self-reproducing hermaphrodite with fairly limited within-population variation, its relative is an outcrossing species with much more extensive genetic variation, making it an ideal parallel model system for evolutionary genetic investigations. Here, we greatly improve on previous assemblies by generating a chromosome-level assembly of the entire genome (124.
View Article and Find Full Text PDFGenomic conflicts may play a central role in the evolution of reproductive barriers. Theory predicts that early-onset hybrid inviability may stem from conflict between parents for resource allocation to offspring. Here, we describe M.
View Article and Find Full Text PDFBackground: Providing culturally safe health care can contribute to improved health among Aboriginal people. However, little is known about how to make hospitals culturally safe for Aboriginal people. This study assessed the impact of an emergency department (ED)-based continuous quality improvement program on: the accuracy of recording of Aboriginal status in ED information systems; incomplete ED visits among Aboriginal patients; and the cultural appropriateness of ED systems and environments.
View Article and Find Full Text PDFSpatially varying selection is a critical driver of adaptive differentiation. Yet, there are few examples where the fitness effects of naturally segregating variants that contribute to local adaptation have been measured in the field. Plant adaptation to harsh soil habitats provides an ideal study system for investigating the genetic basis of local adaptation.
View Article and Find Full Text PDFClosely related, ecologically similar species are often separated at small geographic scales while being broadly sympatric. Both adaptation to abiotic environmental conditions and a variety of biotic interactions may determine small-scale allopatry. In Northern California's coast range, two monkeyflower species, Mimulus guttatus and Mimulus nudatus, can co-occur within local sites but rarely overlap at fine spatial scales, even though they are often separated by less than 1 m.
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