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1.
Genome Biol Evol ; 16(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566597

RESUMO

Transposable elements (TE) play critical roles in shaping genome evolution. Highly repetitive TE sequences are also a major source of assembly gaps making it difficult to fully understand the impact of these elements on host genomes. The increased capacity of long-read sequencing technologies to span highly repetitive regions promises to provide new insights into patterns of TE activity across diverse taxa. Here we report the generation of highly contiguous reference genomes using PacBio long-read and Omni-C technologies for three species of Passerellidae sparrow. We compared these assemblies to three chromosome-level sparrow assemblies and nine other sparrow assemblies generated using a variety of short- and long-read technologies. All long-read based assemblies were longer (range: 1.12 to 1.41 Gb) than short-read assemblies (0.91 to 1.08 Gb) and assembly length was strongly correlated with the amount of repeat content. Repeat content for Bell's sparrow (31.2% of genome) was the highest level ever reported within the order Passeriformes, which comprises over half of avian diversity. The highest levels of repeat content (79.2% to 93.7%) were found on the W chromosome relative to other regions of the genome. Finally, we show that proliferation of different TE classes varied even among species with similar levels of repeat content. These patterns support a dynamic model of TE expansion and contraction even in a clade where TEs were once thought to be fairly depauperate and static. Our work highlights how the resolution of difficult-to-assemble regions of the genome with new sequencing technologies promises to transform our understanding of avian genome evolution.


Assuntos
Elementos de DNA Transponíveis , Pardais , Animais , Elementos de DNA Transponíveis/genética , Pardais/genética , Análise de Sequência de DNA
3.
J Hered ; 114(6): 669-680, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37589384

RESUMO

We announce the assembly of the first de novo reference genome for the California Scrub-Jay (Aphelocoma californica). The genus Aphelocoma comprises four currently recognized species including many locally adapted populations across Mesoamerica and North America. Intensive study of Aphelocoma has revealed novel insights into the evolutionary mechanisms driving diversification in natural systems. Additional insights into the evolutionary history of this group will require continued development of high-quality, publicly available genomic resources. We extracted high molecular weight genomic DNA from a female California Scrub-Jay from northern California and generated PacBio HiFi long-read data and Omni-C chromatin conformation capture data. We used these data to generate a de novo partially phased diploid genome assembly, consisting of two pseudo-haplotypes, and scaffolded them using inferred physical proximity information from the Omni-C data. The more complete pseudo-haplotype assembly (arbitrarily designated "Haplotype 1") is 1.35 Gb in total length, highly contiguous (contig N50 = 11.53 Mb), and highly complete (BUSCO completeness score = 97%), with comparable scaffold sizes to chromosome-level avian reference genomes (scaffold N50 = 66.14 Mb). Our California Scrub-Jay assembly is highly syntenic with the New Caledonian Crow reference genome despite ~10 million years of divergence, highlighting the temporal stability of the avian genome. This high-quality reference genome represents a leap forward in publicly available genomic resources for Aphelocoma, and the family Corvidae more broadly. Future work using Aphelocoma as a model for understanding the evolutionary forces generating and maintaining biodiversity across phylogenetic scales can now benefit from a highly contiguous, in-group reference genome.


Assuntos
Genoma , Passeriformes , Animais , Feminino , Filogenia , Cromossomos , California
4.
J Hered ; 114(5): 549-560, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37395718

RESUMO

The Steller's jay is a familiar bird of western forests from Alaska south to Nicaragua. Here, we report a draft reference assembly for the species generated from PacBio HiFi long-read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 352 scaffolds totaling 1.16 Gb in length. Assembly metrics indicate a highly contiguous and complete assembly with a contig N50 of 7.8 Mb, scaffold N50 of 25.8 Mb, and BUSCO completeness score of 97.2%. Repetitive elements span 16.6% of the genome including nearly 90% of the W chromosome. Compared with high-quality assemblies from other members of the family Corvidae, the Steller's jay genome contains a larger proportion of repetitive elements than 4 crow species (Corvus), but a lower proportion of repetitive elements than the California scrub-jay (Aphelocoma californica). This reference genome will serve as an essential resource for future studies on speciation, local adaptation, phylogeography, and conservation genetics in this species of significant biological interest.


Assuntos
Genoma , Passeriformes , Animais , Genômica , Sequência de Bases , Cromossomos , Cromossomos Sexuais
5.
Am Nat ; 201(2): E23-E40, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36724466

RESUMO

AbstractAnimal coloration serves many biological functions and must therefore balance potentially competing selective pressures. For example, many animals have camouflage in which coloration matches the visual background that predators scan for prey. However, different colors reflect different amounts of solar radiation and may therefore have thermoregulatory implications as well. In this study, we examined geographic variation in dorsal patterning, coloration, and solar reflectance among horned larks (Eremophila alpestris) of the western United States. We found that plumage brightness was positively associated with soil granularity, aridity, and temperature. Plumage redness-both in terms of saturation (i.e., chroma) and hue-was positively associated with soil redness and temperature, while plumage patterning was positively associated with soil granularity. Together, these plumage-environment associations support both background matching and Gloger's rule, a widespread ecogeographic pattern in animal coloration. We also constructed thermoregulatory models that estimated cooling benefits provided by solar reflectance profiles of the dorsal plumage of each specimen based on the collection site. We found increased cooling benefits in hotter, more arid environments. Finally, cooling benefits were positively associated with residual brightness, such that individuals that were brighter than expected based on environmental conditions also had higher cooling benefits, suggesting a trade-off between camouflage and thermoregulation. Together, these data suggest that natural selection has balanced camouflage and thermoregulation in horned larks, and they illustrate how multiple competing evolutionary pressures may interact to shape geographic variation in adaptive phenotypes.


Assuntos
Passeriformes , Aves Canoras , Animais , Regulação da Temperatura Corporal , Evolução Biológica , Solo , Pigmentação
6.
J Hered ; 114(4): 418-427, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-36763048

RESUMO

The California quail (Callipepla californica) is an iconic native bird of scrub and oak woodlands in California and the Baja Peninsula of Mexico. Here, we report a draft reference assembly for the species generated from PacBio HiFi long read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 321 scaffolds totaling 1.08 Gb in length. Assembly metrics indicate a highly contiguous and complete assembly with a contig N50 of 5.5 Mb, scaffold N50 of 19.4 Mb, and BUSCO completeness score of 96.5%. Transposable elements (TEs) occupy 16.5% of the genome, more than previous Odontophoridae quail assemblies but in line with estimates of TE content for recent long-read assemblies of chicken and Peking duck. Together these metrics indicate that the present assembly is more complete than prior reference assemblies generated for Odontophoridae quail. This reference will serve as an essential resource for studies on local adaptation, phylogeography, and conservation genetics in this species of significant biological and recreational interest.


Assuntos
Genômica , Codorniz , Animais , Codorniz/genética , Cromossomos , Elementos de DNA Transponíveis , California
7.
Ecol Evol ; 12(12): e9517, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36466137

RESUMO

The relationship between ecology and morphology is a cornerstone of evolutionary biology, and quantifying variation across environments can shed light on processes that give rise to biodiversity. Three morphotypes of the Steller's Jay (Cyanocitta stelleri) occupy different ecoregions in western North America, which vary in climate and landcover. These morphotypes (Coastal, Interior, Rocky Mountain) differ in size, plumage coloration, and head pattern. We sampled 1080 Steller's Jays from 68 populations (plus 11 outgroups) to address three main questions using data on morphology, plumage, genetics (mtDNA, microsatellites), and ecological niches: (1) How do phenotypic and genetic traits vary within and among populations, morphotypes, and ecoregions? (2) How do population-level differences in Steller's Jays compare with other sister species pairs of North American birds? (3) What can we infer about the population history of Steller's Jays in relation to past climates, paleoecology, and niche evolution? We found substantial morphological, genetic, and ecological differentiation among morphotypes. The greatest genetic divergence separated Coastal and Interior morphotypes from the Rocky Mountain morphotype, which was associated with warmer, drier, and more open habitats. Microsatellites revealed additional structure between Coastal and Interior groups. The deep mtDNA split between Coastal/Interior and Rocky Mountain lineages of Steller's Jay (ND2 ~ 7.8%) is older than most North American avian sister species and dates to approximately 4.3 mya. Interior and Rocky Mountain morphotypes contact across a narrow zone with steep clines in traits and reduced gene flow. The distribution of the three morphotypes coincides with divergent varieties of ponderosa pine and Douglas fir. Species distribution models support multiple glacial refugia for Steller's Jays. Our integrative dataset combined with extensive geographic sampling provides compelling evidence for recognizing at least two species of Steller's Jay.

8.
Proc Natl Acad Sci U S A ; 119(34): e2122667119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35972961

RESUMO

Field biology is an area of research that involves working directly with living organisms in situ through a practice known as "fieldwork." Conducting fieldwork often requires complex logistical planning within multiregional or multinational teams, interacting with local communities at field sites, and collaborative research led by one or a few of the core team members. However, existing power imbalances stemming from geopolitical history, discrimination, and professional position, among other factors, perpetuate inequities when conducting these research endeavors. After reflecting on our own research programs, we propose four general principles to guide equitable, inclusive, ethical, and safe practices in field biology: be collaborative, be respectful, be legal, and be safe. Although many biologists already structure their field programs around these principles or similar values, executing equitable research practices can prove challenging and requires careful consideration, especially by those in positions with relatively greater privilege. Based on experiences and input from a diverse group of global collaborators, we provide suggestions for action-oriented approaches to make field biology more equitable, with particular attention to how those with greater privilege can contribute. While we acknowledge that not all suggestions will be applicable to every institution or program, we hope that they will generate discussions and provide a baseline for training in proactive, equitable fieldwork practices.


Assuntos
Temas Bioéticos , Biologia , Biologia/ética , Humanos
9.
J Infect Dis ; 226(10): 1717-1720, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-35723970

RESUMO

Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is usually asymptomatic or mild and appears to be poorly immunogenic at least in unvaccinated individuals. Here, we found that health care workers vaccinated with 2 doses of Sputnik V and a booster dose of ChAdOx1 mount a vigorous neutralizing-antibody response after Omicron breakthrough infection.


Assuntos
Formação de Anticorpos , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinação , Anticorpos Neutralizantes , Anticorpos Antivirais
10.
Mol Ecol ; 31(6): 1783-1799, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35048444

RESUMO

Genetic structure and phenotypic variation among populations are affected by both geographic distance and environmental variation across species' distributions. Understanding the relative contributions of isolation by distance (IBD) and isolation by environment (IBE) is important for elucidating population dynamics across habitats and ecological gradients. In this study, we compared phenotypic and genetic variation among Horned Lark (Eremophila alpestris) populations from 10 sites encompassing an elevational gradient from low-elevation desert scrub in Death Valley (285 a.s.l.) to high-elevation meadows in the White Mountains of the Sierra Nevada of California (greater than 3000 m a.s.l.). Using a ddRAD data set of 28,474 SNPs aligned to a high-quality reference genome, we compared genetic structure with elevational, environmental, and spatial distance to quantify how different aspects of the landscape drive genomic and phenotypic differentiation in Horned Larks. We found larger-bodied birds were associated with sites that had less seasonality and higher annual precipitation, and longer spurs occurred in soils with more clay and silt content, less sand, and finer fragments. Larks have large neo-sex chromosomes, and we found that associations with elevation and environmental variation were much stronger among neo-sex chromosomes compared to autosomes. Furthermore, we found that putative chromosomal translocations, fusions, and inversions were associated with elevation and may underlie local adaptation across an elevational gradient in Horned Larks. Our results suggest that genetic variation in Horned Larks is affected more by IBD than IBE, but specific phenotypes and genomic regions-particually on neo-sex chromosomes-bear stronger associations with the environment.


Assuntos
Passeriformes , Aves Canoras , Animais , Meio Ambiente , Passeriformes/genética , Fenótipo , Cromossomos Sexuais , Aves Canoras/genética
12.
PeerJ ; 8: e9249, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596039

RESUMO

The New World sparrows (Passerellidae) are a large, diverse group of songbirds that vary in morphology, behavior, and ecology. Thus, they are excellent for studying trait evolution in a phylogenetic framework. We examined lability versus conservatism in morphological and behavioral traits in two related clades of sparrows (Aimophila, Peucaea), and assessed whether habitat has played an important role in trait evolution. We first inferred a multi-locus phylogeny which we used to reconstruct ancestral states, and then quantified phylogenetic signal among morphological and behavioral traits in these clades and in New World sparrows more broadly. Behavioral traits have a stronger phylogenetic signal than morphological traits. Specifically, vocal duets and song structure are the most highly conserved traits, and nesting behavior appears to be maintained within clades. Furthermore, we found a strong correlation between open habitat and unpatterned plumage, complex song, and ground nesting. However, even within lineages that share the same habitat type, species vary in nesting, plumage pattern, song complexity, and duetting. Our findings highlight trade-offs between behavior, morphology, and ecology in sparrow diversification.

14.
PeerJ ; 7: e7388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31404458

RESUMO

We used molecular data to assess the degree of genetic divergence across the breeding range of the orange-crowned warbler (Oreothlypis celata) in western North America with particular focus on characterizing the divergence between O. celata populations on the mainland of southern California and on the Channel Islands. We obtained sequences of the mitochondrial gene ND2 and genotypes at ten microsatellite data for 192 O. celata from populations spanning all four recognized subspecies. We recovered shallow, but significant, levels of divergence among O. celata populations across the species range. Our results suggest that island isolation, subspecies (delineation by morphology, ecological, and life-history characteristics), and isolation-by-distance, in that order, are the variables that best explain the geographic structure detected across the range of O. celata. Populations on the Channel Islands were genetically divergent from those on the mainland. We found evidence for greater gene flow from the Channel Islands population to mainland southern California than from the mainland to the islands. We discuss these data in the context of differentiation in phenotypic and ecological characters.

15.
Mol Ecol ; 28(7): 1692-1708, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30739372

RESUMO

In hybrid zones in which two divergent taxa come into secondary contact and interbreed, selection can maintain phenotypic diversity despite widespread genetic introgression. Red-breasted (Sphyrapicus ruber) and red-naped (S. nuchalis) sapsuckers meet and hybridize along a narrow contact zone that stretches from northern California to southern British Columbia. We found strong evidence for changes in the structure of this hybrid zone across time, with significant temporal shifts in allele frequencies and in the proportions of parental phenotypes across the landscape. In addition to these shifts, we found that differences in plumage predict genetic differences (R2  = 0.80), suggesting that plumage is a useful proxy for assessing ancestry. We also found a significant bimodal distribution of hybrids across the contact zone, suggesting that premating barriers may be driving reproductive isolation, perhaps as a result of assortative mating based on plumage differences. However, despite evidence of selection and strong patterns of population structure between parental samples, we found only weak patterns of genetic divergence. Using museum specimens and genomic data, this study of sapsuckers provides insight into the ways in which phenotypic and genetic structure have changed over a 40-year period, as well as insight into the mechanisms that may contribute to the maintenance of the hybrid zone over time.


Assuntos
Genética Populacional , Hibridização Genética , Modelos Genéticos , Passeriformes/genética , Animais , California , Plumas , Frequência do Gene , Oregon , Passeriformes/classificação , Fenótipo , Fatores de Tempo
16.
J Egypt Natl Canc Inst ; 30(2): 81-83, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29779939

RESUMO

We discuss the diagnosis and the management of endometrial carcinoma in a single horn of bicornuate uterus in a 64-year-old woman as a case report. The case underwent laparoscopic radical hysterectomy and bilateral iliac lymphadenectomy. The gross examination of the uterus revealed a bicornuate uterus with a greater horn of 12 × 9 × 8 cm and a smaller horn of 10 × 3 cm. The cavity of the greater horn showed a neoplastic growth of 10 cm with infiltration of about 1,8 cm of the myometrium from whole thickness of 1.9 cm. while the other horn was free of tumor tissue. The microscopic examination of the uterus revealed G2 endometrioid adenocarcinoma of the endometrium of the greater horn with infiltration of more than 50% of the myometrium. In the presence of bicornuate uterus, a bilateral endometrial biopsy should be performed in order to reduce the risk of delayed or missed diagnosis. The management of a case of bicornuate unicollis uterus with endometrial carcinoma in only one horn is the same as patients with endometrial cancer in single uterus and depends mainly on stage and histological grade of the tumor. The possibility of existence of a separate uterine cavity should always be considered when endometrial cancer is clinically suspected but pathology fails to confirm the diagnosis. This points out the importance of a careful physical examination and radiographic evaluation in such cases.


Assuntos
Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade
17.
PLoS Biol ; 15(11): e2003318, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29161253

RESUMO

Museums have an untapped potential to engage students in hands-on learning. Here, we describe the development of a tiered museum-based program at the University of California, Berkeley as a model for engaging undergraduates in biodiversity science. This decade-long effort to increase student participation in collections demonstrates the mutual benefits of undergraduate involvement. Museums benefit from critical help in collections care and an increased intellectual vitality, while students simultaneously gain essential research skills and an unparalleled exposure to biodiversity. Five first steps to creating a program are: dedicate a coordinator, offer credit, diversify participation, create a tiered structure, and build community.


Assuntos
Educação/métodos , Museus/estatística & dados numéricos , Ciência/educação , Biodiversidade , Humanos , Aprendizagem , Pesquisa , Estudantes
18.
Medicina (B Aires) ; 77(3): 167-172, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28643671

RESUMO

Health literacy (HL) is a measure of a patient ability to read, understand and to take decisions on medical instructions. Patients with inadequate HL have poorer health outcomes than those with adequate HL. There is little information on HL levels in diabetic patients in Argentina. The aim of this study was to explore the association between HL and glycemic control in diabetic patients from a university hospital in Argentina. HL was assessed with the Short Assessment of Health Literacy for Spanish-speaking Adults (SAHLSA), glycemic control through glycosylated hemoglobin A1c (HbA1c); 156 patients (58% women) took part in the study. Average SAHLSA score was 35 (range: 11-50). Patients with inadequate values of HL had HbA1c of 8.15% vs. 7.15% among those with adequate HL (p = 0.0001). The multiple linear regression shows that inadequate HL was significantly associated with poorer glycemic control (ß = -0.05 IC 95% -0.07; -0.02, p < 0.001). Efforts should focus on developing interventions to improve glycemic control among patients with inadequate HL.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Letramento em Saúde/estatística & dados numéricos , Educação de Pacientes como Assunto/métodos , Argentina , Compreensão , Estudos Transversais , Avaliação Educacional , Escolaridade , Feminino , Humanos , Hiperglicemia/prevenção & controle , Masculino , Pessoa de Meia-Idade
19.
Medicina (B.Aires) ; 77(3): 167-172, jun. 2017. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-894452

RESUMO

La alfabetización en salud (AS) es una medida de la capacidad de los pacientes de leer, comprender y tomar decisiones en base a instrucciones médicas. La inadecuada AS se asocia con peor estado de salud en pacientes con enfermedades crónicas. Es escasa la información sobre el nivel de alfabetización en pacientes diabéticos en Argentina. Se realizó este estudio con el objeto de estimar la relación de inadecuada AS y el control de la diabetes, evaluada a través del valor de la hemoglobina A1c en diabéticos tratados con insulina que concurren a un hospital universitario de Argentina. La AS se evaluó con el Short Assessment of Health Literacy for Spanish-speaking Adults (SAHLSA) y se evaluó el control de la glucemia por el último valor de hemoglobina A1c. Participaron 156 pacientes seleccionados en forma aleatoria, 58% mujeres. El puntaje promedio de SALHSA fue 35 (rango: 11-50). Se encontró inadecuada AS en 94 pacientes (60.3%). La HbA1c promedio en los pacientes con inadecuada AS fue 8.15% vs 7.15% entre los que tenían adecuada AS (p = 0.0001). La regresión lineal múltiple mostró que la inadecuada AS se asocia en forma significativa con el mal control de la glucemia (β = -0.05 IC 95% -0.07; -0.02, p < 0.001). En conclusión, sería necesario implementar medidas para garantizar la educación de los pacientes con limitada AS.


Health literacy (HL) is a measure of a patient ability to read, understand and to take decisions on medical instructions. Patients with inadequate HL have poorer health outcomes than those with adequate HL. There is little information on HL levels in diabetic patients in Argentina. The aim of this study was to explore the association between HL and glycemic control in diabetic patients from a university hospital in Argentina. HL was assessed with the Short Assessment of Health Literacy for Spanish-speaking Adults (SAHLSA), glycemic control through glycosylated hemoglobin A1c (HbA1c); 156 patients (58% women) took part in the study. Average SAHLSA score was 35 (range: 11-50). Patients with inadequate values of HL had HbA1c of 8.15% vs. 7.15% among those with adequate HL (p = 0.0001). The multiple linear regression shows that inadequate HL was significantly associated with poorer glycemic control (β = -0.05 IC 95% -0.07; -0.02, p < 0.001). Efforts should focus on developing interventions to improve glycemic control among patients with inadequate HL.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/métodos , Diabetes Mellitus Tipo 2/prevenção & controle , Letramento em Saúde/estatística & dados numéricos , Argentina , Estudos Transversais , Compreensão , Avaliação Educacional , Escolaridade , Hiperglicemia/prevenção & controle
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