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1.
Front Immunol ; 15: 1440911, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39229273

RESUMEN

Introduction: The human leukocyte antigen (HLA) evolutionary divergence (HED) reflects immunopeptidome diversity and has been shown to predict the response of tumors to immunotherapy. Its impact on allogeneic hematopoietic stem cell transplantation (HSCT) is controversial in different studies. Methods: In this study, we retrospectively analyzed the clinical impact of class I and II HED in 225 acute lymphoblastic leukemia patients undergoing HSCT from related haploidentical donors. The HED for recipient, donor, and donor-recipient pair was calculated based on Grantham distance, which accounts for variations in the composition, polarity, and volume of each amino acid within the peptide-binding groove of two HLA alleles. The median value of HED scores was used as a cut-off to stratify patients with high or low HED. Results: The class I HED for recipient (R_HEDclass I) showed the strongest association with cumulative incidence of relapse (12.2 vs. 25.0%, P = 0.00814) but not with acute graft-versus-host disease. The patients with high class II HED for donor-recipient (D/R_HEDclass II) showed a significantly higher cumulative incidence of severe aGVHD than those with low D/R_HEDclass II (24.0% vs. 6.1%, P = 0.0027). Multivariate analysis indicated that a high D/R_HEDclass II was an independent risk factor for the development of severe aGVHD (P = 0.007), and a high R_HEDclass I had a more than two-fold reduced risk of relapse (P = 0.028). However, there was no discernible difference in overall survival (OS) or disease-free survival (DFS) for patients with high or low HED, which was inconsistent with the previous investigation. Discussion: While the observation are limited by the presented single center retrospective cohort, the results show that HED has poor prognostic value in OS or DFS, as well as the associations with relapse and aGVHD. In haploidentical setting, class II HED for donor-recipient pair (D/R_HEDclass II) is an independent and novel risk factor for finding the best haploidentical donor, which could potentially influence clinical practice if verified in larger cohorts.


Asunto(s)
Selección de Donante , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Masculino , Femenino , Adulto , Adolescente , Persona de Mediana Edad , Niño , Estudios Retrospectivos , Factores de Riesgo , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/genética , Adulto Joven , Antígenos HLA/genética , Antígenos HLA/inmunología , Preescolar , Trasplante Haploidéntico , Donantes de Tejidos , Evolución Molecular
2.
Heliyon ; 10(16): e36062, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39229510

RESUMEN

Wheat is an important crop for food security, providing a source of protein and energy for the growing population in Ethiopia. However, both biotic and abiotic factors limit national wheat productivity. The availability of genetically diverse wheat genotypes is crucial for developing new wheat varieties that are both high-yielding and resilient to stress. Therefore, this field trial aimed to assess phenotypic variation and relationship among ICARDA-derived bread wheat genotypes using multivariate analysis techniques. The trial was conducted at three locations: Enewari, Wogere, and Kulumsa using an alpha lattice design with two replications during the main cropping seasons of 2022 and 2023. Phenotypic data on eight agronomic traits and the severity of yellow rust were collected and R programming was used for data analysis. Individual and combined location data analysis of variance showed significant differences (p ≤ 0.05) among genotypes for most of the studied traits. The highest heritability and genetic advance as a percentage of the mean were observed in days to heading (90.8, 21.29), plant height (72.4, 28.6), seeds per spike (61.7, 28), thousand kernel weight (61.9, 12), and area under the disease progress curve (67, 39.8), suggesting a predominance of additive gene action. Grain yield showed a strong positive correlation with days to maturity, plant height, spike length, spikelet per spike, and thousand kernel weight for each location. Dendrogram and phylogenetic tree methods were used to group genotypes into four genetically distinct clusters. Cluster II and III had the greatest inter-cluster distance, indicating higher diversity among their genotypes. This study identified new candidate genotypes with superior agronomic performance, high grain yield traits, and robust resistance to yellow rust, making them valuable for both current and future wheat breeding programs. Additionally, the comprehensive dataset produced in this study could facilitate the identification of genetic variations influencing desirable traits through genome-wide association analysis.

3.
R Soc Open Sci ; 11(6): 240601, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39253402

RESUMEN

Genetic differentiation between populations inhabiting ecologically different habitats might appear because of limited dispersal and gene flow, which may lead to patterns of phenotypic divergence and local adaptation. In this study, we use dispersal, genotypic (24 microsatellite loci) and phenotypic (body size and clutch size) data to analyse patterns of genetic structuring and phenotypic divergence in a blue tit (Cyanistes caeruleus) population inhabiting a continuous and heterogeneous woodland along a valley. The two slopes of the valley differ in their forest formations and environmental conditions. Findings showed that most blue tits reproduced within their natal slope. Accordingly, microsatellite analyses revealed that populations of blue tits established in the two slopes show subtle genetic differentiation. The two genetic populations diverged in clutch size, exceeding the level of differentiation expected based on genetic drift, hence suggesting divergent selection (or other processes promoting divergence) on this life-history trait. Our findings reveal that restricted dispersal and spatial heterogeneity may lead to genetic differentiation among bird populations at a surprisingly small scale. In this respect, it is worth highlighting that such differentiation occurs for an organism with high dispersal capacity and within a continuous woodland. Moreover, we show that small-scale ecological differences, together with limited gene flow, can result in selection favouring different phenotypes even within the same continuum population.

4.
Orthod Craniofac Res ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258596

RESUMEN

AIM: Evaluate constitutional differences in chin morphology and volume, and mandibular tooth size, between different facial divergence patterns. MATERIALS AND METHODS: The sample consisted of 284 pretreatment cone beam computed tomography (CBCT) images of growing and non-growing patients who were stratified into 4 groups based on mandibular plane inclination to cranial base (SN) angle. Linear and angular measurements were made on the lateral CBCT images: mandibular lateral incisor crown (I-C) total (I-A) lengths, the distances between point D (centre of symphysis) and both incisor apex (D-A) and menton (D-Me) and between cemento-enamel junction and menton (CEJ-Me); chin width at the level of the central incisor apex (CWA) and point D (CWD); and the angles of the anterior and posterior symphyseal slopes. The volume of the symphysis was measured using a specialized 3D imaging software. Group differences and associations between parameters were gauged through the three-way ANOVA analysis. RESULTS: I-C, I-A, D-A, D-Me and CEJ-Me were greater in the hyperdivergent group (p < .001). CWA and CWD were wider in the hypodivergent group (p = .003). Volume of the chin and inter-slope angles were similar in all groups (p > .05). The anterior slope angle decreased with hyperdivegence (p < .005) in opposite pattern to the posterior slope angle (p < .005). CONCLUSIONS: Shape differences in mandibular symphysis were observed between opposite divergence patterns. Mandibular incisors were longer with hyperdivergence and shorter with hypodivergence. However, chin volumes were similar across divergence groups. These findings underline the role of genetic and environmental factors that impact facial growth.

5.
Zoolog Sci ; 41(4): 385-391, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39093284

RESUMEN

The Japanese Archipelago hosts a rich butterfly fauna, and elucidating the genetic structures of multiple species is necessary to clarify their formation processes. This study aimed to reveal the genetic structure and distribution formation process of Parnassius citrinarius, which is widely distributed across the Japanese Archipelago from Hokkaido to Shikoku, through phylogeographic analysis based on the mitochondrial cytochrome c oxidase subunit I (COI) gene sequence. Thirty haplotypes were revealed from 311 individuals from 47 sites, indicating significant differences in the genetic structures between the eastern and western parts of the Japanese Archipelago. In Eastern Japan, multiple genetic clusters were found, with some sites harboring two clusters. The divergence times among populations in Eastern Japan were relatively recent, and no genetic differentiation was observed between regions, including between Hokkaido and Honshu, which are separated by a narrow strait. In contrast, in Western Japan, including Shikoku, unique genetic clusters were observed in each region. The phylogenetic relationships among populations were regionally clustered, and the divergence times were relatively ancient. The distribution and genetic structure of P. citrinarius in the Japanese Archipelago have been significantly influenced by temperature fluctuations and the presence of geographical barriers during the Pleistocene glacial-interglacial cycles, including the potential formation of refugia in Western Japan.


Asunto(s)
Mariposas Diurnas , ADN Mitocondrial , Variación Genética , Filogeografía , Animales , Japón , ADN Mitocondrial/genética , Mariposas Diurnas/genética , Filogenia , Distribución Animal , Complejo IV de Transporte de Electrones/genética
6.
Front Plant Sci ; 15: 1410372, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39100082

RESUMEN

Understanding the invasion of moso bamboo (Phyllostachys edulis) into adjacent evergreen broadleaf forest based on functional traits is crucial due to its significant influence on ecosystem processes. However, existing research has primarily focused on above- or below-ground traits in isolation, lacking a comprehensive integration of both. In this study, we conducted a trait-based analysis including 23 leaf traits and 11 root traits in three forest types - bamboo forest, mixed bamboo and broadleaf forest, and evergreen broadleaf forest - to investigate trait differences, phenotypic integration, and above- and below-ground resource strategies in bamboo and broadleaf species. Our findings demonstrated significant differences in leaf and root key traits between bamboo and broadleaf species, strongly supporting the "phenotypic divergence hypothesis". Bamboo exhibited stronger trait correlations compared to broadleaf species, indicating higher phenotypic integration. Above- and below-ground strategies were characterized by trade-offs rather than coordination, resulting in a multi-dimensional trait syndrome. Specifically, a unidimensional leaf economics spectrum revealed that bamboo with higher leaf N concentrations (LNC), P concentrations (LPC), and specific leaf area (SLA) adopted a "fast acquisitive" above-ground strategy, while broadleaf species with thicker leaves employed a "slow conservative" above-ground strategy. A two-dimensional root trait syndrome indicated a "conservation" gradient with bamboo adopting a "slow conservative" below-ground strategy associated with higher root tissue density (RTD), and broadleaf species exhibiting a "fast acquisitive" below-ground strategy linked to higher root N concentrations (RNC) and P concentrations (RPC), and a "collaboration" gradient probably ranging from broadleaf species with a "do-it-yourself" strategy characterized by high specific root length (SRL), to bamboo adopting an "outsourcing" strategy with thicker roots. In conclusion, key trait divergence from coexisting broadleaf species, higher phenotypic integration, and multi-dimensional opposite above- and below-ground resource strategies confer competitive advantages to moso bamboo, shedding light on the mechanistic understanding of its invasion into subtropical evergreen broadleaf forest and providing theoretical guidance for maintaining the stability of subtropical forest ecosystem.

7.
Ecol Evol ; 14(8): e70126, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39114168

RESUMEN

To study the interspecific differentiation characteristics of species originating from recent radiation, the genotyping-by-sequencing (GBS) technique was used to explore the kinship, population structure, gene flow, genetic variability, genotype-environment association and selective sweeps of Picea asperata complex with similar phenotypes from a genome-wide perspective. The following results were obtained: 14 populations of P. asperata complex could be divided into 5 clades; P. wilsonii and P. neoveitchii diverged earlier and were more distantly related to the remaining 6 spruce species. Various geological events have promoted the species differentiation of P. asperata complex. There were four instances of gene flow among P. koraiensis, P. meyeri, P. asperata, P. crassifolia and P. mongolica. The population of P. mongolica had the highest level of nucleotide diversity, and P. neoveitchii may have experienced a bottleneck recently. Genotype-environment association found that a total of 20,808 genes were related to the environmental variables, which enhanced the adaptability of spruce in different environments. Genes that were selectively swept in the P. asperata complex were primarily associated with plant stress resistance. Among them were some genes involved in plant growth and development, heat stress, circadian rhythms and flowering. In addition to the commonly selected genes, different spruce species also displayed unique genes subjected to selective sweeps that improved their adaptability to different habitats. Understanding the interspecific gene flow and adaptive evolution of Picea species is beneficial to further understanding the species relationships of spruce and can provide a basis for studying spruce introgression and functional genomics.

8.
Kidney Int Rep ; 9(8): 2498-2513, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39156165

RESUMEN

Introduction: BK polyomavirus-associated nephropathy (BKPyVAN) is a significant complication in kidney transplant recipients (KTRs), associated with a higher level of plasmatic BK polyomavirus (BKPyV) replication and leading to poor graft survival. Methods: We prospectively followed-up with 100 KTRs with various degrees of BKPyV reactivation (no BKPyV reactivation, BKPyV-DNAuria, BKPyV-DNAemia, and biopsy-proven BKPyVAN [bp-BKPyVAN], 25 patients per group) and evaluated BKPyV-specific T cell functionality and phenotype. Results: We demonstrate that bp-BKPyVAN is associated with a loss of BKPyV-specific T cell proliferation, cytokine secretion, and cytotoxic capacities. This severe functional impairment is associated with an overexpression of lymphocyte inhibitory receptors (programmed cell death 1 [PD1], cytotoxic T lymphocyte-associated protein 4, T cell immunoreceptor with Ig and ITIM domains, and T cell immunoglobulin and mucin domain-containing-3), highlighting an exhausted-like phenotype of BKPyV-specific CD4 and CD8 T cells in bp-BKPyVAN. This T cell dysfunction is associated with low class II donor-recipient human leukocyte antigen (HLA) divergence. In contrast, in the context of higher class II donor-recipient HLA (D/R-HLA) divergence, allogeneic CD4 T cells can provide help that sustains BKPyV-specific CD8 T cell responses. In vitro, allogeneic HLA-mismatched CD4 T cells rescue BKPyV-specific CD8 T cell responses. Conclusion: Our findings suggest that in KTRs, allogeneic CD4 T cells can help to maintain an effective BKPyV-specific CD8 T cell response that better controls BKPyV replication in the kidney allograft and may protect against BKPyVAN.

9.
J Appl Stat ; 51(11): 2157-2177, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39157274

RESUMEN

The time-varying kernel density estimation relies on two free parameters: the bandwidth and the discount factor. We propose to select these parameters so as to minimize a criterion consistent with the traditional requirements of the validation of a probability density forecast. These requirements are both the uniformity and the independence of the so-called probability integral transforms, which are the forecast time-varying cumulated distributions applied to the observations. We thus build a new numerical criterion incorporating both the uniformity and independence properties by the mean of an adapted Kolmogorov-Smirnov statistic. We apply this method to financial markets during the onset of the COVID-19 crisis. We determine the time-varying density of daily price returns of several stock indices and, using various divergence statistics, we are able to describe the chronology of the crisis as well as regional disparities. For instance, we observe a more limited impact of COVID-19 on financial markets in China, a strong impact in the US, and a slow recovery in Europe.

10.
Insects ; 15(8)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39194797

RESUMEN

The two cryptic grasshopper species of the genus Stenobothrus, S. eurasius and S. hyalosuperficies, demonstrate different acoustic behavior despite a strong similarity in morphology. A hybridization between these species is possible in the contact zone; however, there are little molecular data about the relationships of these species. The analysis of the mtDNA control region (CR) reveals that haplotypes of S. hyalosuperficies have more in common with the more distant Stenobothrus species than with the closely related S. eurasius. In the contact zone, S. eurasius has mt-haplotypes shared with S. hyalosuperficies, which might indicate an introgression of mtDNA from S. hyalosuperficies to the S. eurasius gene pool. We also analyze the structure and evolutionary rate of the mtDNA CR for the Stenobothrus genus and estimate the time of divergence of the species within the genus. The phylogenetic tree of the tribe Stenobothrini reconstructed with either the CR or COI gave the same four groups. The phylogenetic tree of the Stenobothrus genus has a star-like topology with each mtDNA haplotype found in any analyzed species, except S. eurasius, which forms a separate branch. The maximum degree of incomplete lineage sorting can demonstrate either ancestral polymorphism or introgression.

11.
J Imaging ; 10(8)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39194967

RESUMEN

Computed tomography (CT) imaging plays a crucial role in various medical applications, but noise in projection data can significantly degrade image quality and hinder diagnosis accuracy. Iterative algorithms for tomographic image reconstruction outperform transform methods, especially in scenarios with severe noise in projections. In this paper, we propose a method to dynamically adjust two parameters included in the iterative rules during the reconstruction process. The algorithm, named the parameter-extended expectation-maximization based on power divergence (PXEM), aims to minimize the weighted extended power divergence between the measured and forward projections at each iteration. Our numerical and physical experiments showed that PXEM surpassed conventional methods such as maximum-likelihood expectation-maximization (MLEM), particularly in noisy scenarios. PXEM combines the noise suppression capabilities of power divergence-based expectation-maximization with static parameters at every iteration and the edge preservation properties of MLEM. The experimental results demonstrated significant improvements in image quality in metrics such as the structural similarity index measure and peak signal-to-noise ratio. PXEM improves CT image reconstruction quality under high noise conditions through enhanced optimization techniques.

12.
Drug Alcohol Depend ; 263: 112430, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39216198

RESUMEN

OBJECTIVE: Racialized health inequities in substance use-related harms might emerge from differential access to syringe service programs (SSPs). To explore this, we examined the association between county-level racialized environments, other factors, and (1) SSP presence, and (2) per capita syringe and (3) naloxone distribution. METHODS: 2021 US National Survey of SSP data (n=295/412;72 % response rate) was used to identify SSP presence and the sum of syringes and naloxone doses distributed in 2020 by county. Study measures included racial residential segregation (RRS; i.e., divergence and dissimilarity indexes for Black:Non-Hispanic White & Hispanic:Non-Hispanic White) and covariates (i.e., demographic proportions, urban/suburban/rural classifications, 2020 US presidential Republican vote share, and overdose mortality from 2019). We used logit Generalized Estimating Equations to determine factors associated with county-level SSP presence, and zero inflated negative binomial regression models to determine factors associated with per capita syringe and naloxone distribution. RESULTS: SSPs were reported in 9 % (283/3106) of US counties. SSP presence was associated with higher divergence and dissimilarity indexes, urban and suburban counties, higher opioid overdose mortality, and lower 2020 Republican presidential vote share. Per capita syringes distributed was associated with lower RRS (divergence and Hispanic:White dissimilarity), lower racially minoritized population proportions and rural counties, while per capita naloxone distribution was associated with lower Hispanic and "other" population proportions, and rural counties. CONCLUSIONS: Racialized environments are associated with SSP presence but not the scope of those programs. Preventing HIV and HCV outbreaks, and overdose deaths requires addressing community level factors that influence SSP implementation and accessibility.


Asunto(s)
Naloxona , Programas de Intercambio de Agujas , Humanos , Naloxona/uso terapéutico , Estados Unidos/epidemiología , Sobredosis de Droga/epidemiología , Antagonistas de Narcóticos/uso terapéutico , Accesibilidad a los Servicios de Salud , Hispánicos o Latinos , Población Blanca
13.
Ecol Evol ; 14(8): e70105, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39100205

RESUMEN

This study explores how climate variables influenced the evolution and diversification of Neurergus newts within the Irano-Anatolian biodiversity hotspot. We use a dated phylogenetic tree and climatic niche models to analyze their evolutionary history and ecological preferences. Using genetic data from nuclear (KIAA) and mitochondrial (16s and 12s) genes, we estimate divergence times and identify four major Neurergus clades. The initial speciation event occurred approximately 11.3 million years ago, coinciding with the uplift of the Zagros and Anatolian mountains. This geological transformation isolated newt populations, likely triggering the first speciation event. By integrating potential geographic distribution with climate variables, we reconstruct ancestral niche occupancy profiles. This highlights the critical roles of temperature and precipitation in shaping Neurergus habitat preferences and distribution. We observe both phylogenetic niche conservatism and divergence, with niche divergence playing a dominant role in diversification. This research emphasizes the complex interplay of geography, climate, and ecology in speciation and the vulnerability of isolated mountain newt populations to environmental changes.

14.
Mol Phylogenet Evol ; 200: 108185, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39209047

RESUMEN

Petaluridae (Odonata: Anisoptera) is a relict dragonfly family, having diverged from its sister family in the Jurassic, of eleven species that are notable among odonates (dragonflies and damselflies) for their exclusive use of fen and bog habitats, their burrowing behavior as nymphs, large body size as adults, and extended lifespans. To date, several nodes within this family remain unresolved, limiting the study of the evolution of this peculiar family. Using an anchored hybrid enrichment dataset of over 900 loci we reconstructed the species tree of Petaluridae. To estimate the temporal origin of the genera within this family, we used a set of well-vetted fossils and a relaxed molecular clock model in a divergence time estimation analysis. We estimate that Petaluridae originated in the early Cretaceous and confirm the existence of monophyletic Gondwanan and Laurasian clades within the family. Our relaxed molecular clock analysis estimated that these clades diverged from their MRCA approximately 160 mya. Extant lineages within this family were identified to have persisted from 6 (Uropetala) to 120 million years (Phenes). Our biogeographical analyses focusing on a set of key regions suggest that divergence within Petaluridae is largely correlated with continental drift, the exposure of land bridges, and the development of mountain ranges. Our results support the hypothesis that species within Petaluridae have persisted for tens of millions of years, with little fossil evidence to suggest widespread extinction in the family, despite optimal conditions for the fossilization of nymphs. Petaluridae appear to be a rare example of habitat specialists that have persisted for tens of millions of years.


Asunto(s)
Fósiles , Odonata , Filogenia , Animales , Odonata/genética , Odonata/clasificación , Extinción Biológica , Modelos Genéticos , Teorema de Bayes , Análisis de Secuencia de ADN , Evolución Molecular
15.
Mol Biol Evol ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39213383

RESUMEN

Determining the origins of novel genes and the mechanisms driving the emergence of new functions is challenging yet crucial for understanding evolutionary innovations. Recently evolved fish antifreeze proteins (AFPs) offer a unique opportunity to explore these processes, particularly the near-identical type I AFP (AFPI) found in four phylogenetically divergent fish taxa. This study tested the hypothesis of protein sequence convergence beyond functional convergence in three unrelated AFPI-bearing fish lineages. Through comprehensive comparative analyses of newly sequenced genomes of winter flounder and grubby sculpin, along with available high-quality genomes of cunner and 14 other related species, the study revealed that near-identical AFPI proteins originated from distinct genetic precursors in each lineage. Each lineage independently evolved a de novo coding region for the novel ice-binding protein while repurposing fragments from their respective ancestors into potential regulatory regions, representing partial de novo origination-a process that bridges de novo gene formation and the neofunctionalization of duplicated genes. The study supports existing models of new gene origination and introduces new ones: the Innovation-Amplification-Divergence (IAD) model, where novel changes precede gene duplication; the newly proposed Duplication-Degeneration-Divergence (DDD) model, which describes new functions arising from degenerated pseudogenes; and the DDD gene fission model, where each new sibling gene differentially degenerate and renovate distinct functional domains from their parental gene. These findings highlight the diverse evolutionary pathways through which a novel functional gene with convergent sequences at the protein level can evolve across divergent species, advancing our understanding of the mechanistic intricacies in new gene formation.

16.
Appl Plant Sci ; 12(4): e11612, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184201

RESUMEN

Premise: Hybridization and polyploidization are common in vascular plants and important drivers of biodiversity by facilitating speciation and ecological diversification. A primary limitation to making broad synthetic discoveries in hybrid and allopolyploid biodiversity research is the absence of a standardized framework to compare data across studies and biological scales. Methods: Here, I present a new quantitative framework to investigate and interpret patterns in hybrid and allopolyploid biology called the divergence index (DI). The DI framework produces standardized data that are comparable across studies and variables. To show how the DI framework can be used to synthesize data, I analyzed published biochemical, physiological, and ecological trait data of hybrids and allopolyploids. I also apply key ecological and evolutionary concepts in hybrid and polyploid biology to translate nominal outcomes, including transgression, intermediacy, expansion, and contraction, in continuous DI space. Results: Biochemical, physiological, ecological, and evolutionary data can all be analyzed, visualized, and interpreted in the DI framework. The DI framework is particularly suited to standardize and compare variables with very different scales. When using the DI framework to understand niche divergence, a metric of niche overlap can be used to complement insights to centroid and breadth changes. Discussion: The DI framework is an accessible framework for hybrid and allopolyploid biology and represents a flexible and intuitive tool that can be used to reconcile outstanding problems in plant biodiversity research.

17.
BMC Plant Biol ; 24(1): 784, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160457

RESUMEN

Various attributes are hypothesized to facilitate the dominance of an invasive species in non-native geographical and ecological regimes. To explore the characteristic invasive attributes of the family Asteraceae, a comparative study was conducted among nine species of this family, co-occurring in the western Himalayan region. Based on their nativity and invasion status, the species were categorized as "Invasive", "Naturalized", and "Native". Fifteen plant functional traits, strongly linked with invasion, were examined in the test species. The analyses revealed a strong dissimilarity between all the plant functional traits (except leaf carbon [Leaf C]) represented by "Invasive" and "Native" categories and most of the traits (except leaf area [LA], leaf nitrogen [Leaf N], Leaf C, and leaf carbon-nitrogen ratio [C: N]) represented by the "Naturalized" and "Native" categories. Similarly, "Invasive" and "Naturalized" categories also varied significantly for most of the traits (except Leaf N, Leaf C, capitula per m² population [Cm²], seeds per capitula [Scapitula], and seed mass). Invasive species are characterized by high LA, specific leaf area [SLA] and germination, and low C:N and leaf construction costs [LCC]. Most of the traits represented by native species justify their non-invasive behavior; whereas the naturalized species, despite having better size metrics (plant height), resource investment strategy (aboveground non-reproductive biomass [BNR], and aboveground reproductive biomass [BR]), and reproductive output (capitula per individual plant [Cplant], and seeds per individual plant [Splant]) failed to invade, which implies that the role of these functional aspects in imparting invasion potential to a species is not consistent in all the ecosystems and/or phylogenetic groups. Results of PCA revealed that trait divergence plays a more imperative role in invasion success than naturalization in the species of the family Asteraceae. The present study is intended to refine the pre-generalized invasion concepts associated with family Asteraceae to ensure more accurate identification of the potential invaders and better management of the existing ones.


Asunto(s)
Asteraceae , Especies Introducidas , Asteraceae/fisiología , Asteraceae/genética , Hojas de la Planta/fisiología , Hojas de la Planta/anatomía & histología , Hojas de la Planta/crecimiento & desarrollo , Carbono/metabolismo , Especificidad de la Especie
18.
Cell Rep ; 43(9): 114671, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215999

RESUMEN

Recent discoveries have revealed remarkable complexity within olfactory sensory neurons (OSNs), including the existence of two OSN populations based on the expression of Cd36. However, the regulatory mechanisms governing this cellular diversity in the same cell type remain elusive. Here, we show the preferential expression of 79 olfactory receptors in Cd36+ OSNs and the anterior projection characteristics of Cd36+ OSNs, indicating the non-randomness of Cd36 expression. The integrated analysis of single-cell RNA sequencing (scRNA-seq) and scATAC-seq reveals that the differences in Cd36+/- OSNs occur at the immature OSN stage, with Mef2a and Hdac9 being important regulators of developmental divergence. We hypothesize that the absence of Hdac9 may affect the activation of Mef2a, leading to the up-regulation of Mef2a target genes, including teashirt zinc finger family member 1 (Tshz1), in the Cd36+ OSN lineage. We validate that Tshz1 directly promotes Cd36 expression through enhancer bindings. Our study unravels the intricate regulatory landscape and principles governing cellular diversity in the olfactory system.

19.
New Phytol ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39205459

RESUMEN

Accurate divergence times are essential for interpreting and understanding the context in which lineages have evolved. Over the past several decades, debates have surrounded the discrepancies between the inferred molecular ages of crown angiosperms, often estimated from the Late Jurassic into the Permian, and the fossil record, placing angiosperms in the Early Cretaceous. That crown angiosperms could have emerged as early as the Permian or even the Triassic would have major implications for the paleoecological context of the origin of one of the most consequential clades in the tree of life. Here, we argue, and demonstrate through simulations, that the older ages inferred from molecular data and relaxed-clock models are misled by lineage-specific rate heterogeneity resulting from life history changes that occurred several times throughout the evolution of vascular plants. To overcome persistent discrepancies in age estimates, more biologically informed and realistic models should be developed, and our results should be considered in the context of their biological implications before we accept inferences that are a major departure from our strongest evidence.

20.
Bioengineering (Basel) ; 11(8)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39199792

RESUMEN

Three laryngeal models were used to investigate the aerodynamic and elastic properties of vocal fold vibration: cadaveric human, excised canine, and synthetic silicone vocal folds. The aim was to compare the characteristics of these models to enhance our understanding of phonatory mechanisms. Flow and medial glottal wall geometry were acquired via particle image velocimetry. Elastic properties were assessed from force-displacement tests. Relatively, the human larynges had higher fundamental frequency values, while canine and synthetic models exhibited greater flow rates. Canine models demonstrated the highest divergence angles and vertical stiffness gradients followed by the human model, both displaying flow separation vortices during closing. Synthetic models, whose advantage is their accessibility and repeatability, displayed the lowest glottal divergence angles and total circulation values compared to tissue models with no flow separation vortices. The elasticity tests revealed that tissue models showed significant hysteresis and vertical stiffness gradients, unlike the synthetic models. These results underscore the importance of model selection based on specific research needs and highlight the potential of canine and synthetic models for controlled experimental studies in phonation.

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