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1.
Mol Ecol ; 33(2): e17207, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37975486

RESUMO

The evolution of reproductive barriers, that is, the speciation process, implies the limitation of gene flow between populations. Different patterns of genomic differentiation throughout the speciation continuum may provide insights into the causal evolutionary forces of species divergence. In this study, we analysed a cryptic species complex of the genus Hetaerina (Odonata). This complex includes H. americana and H. calverti; however, in H. americana two highly differentiated genetic groups have been previously detected, which, we hypothesize, may correspond to different species with low morphological variation. We obtained single nucleotide polymorphism (SNP) data for 90 individuals belonging to the different taxa in the complex and carried out differentiation tests to identify genetic isolation. The results from STRUCTURE and discriminant analysis of principal components (DAPC), based on almost 5000 SNPs, confirmed the presence of three highly differentiated taxa. Also, we found FST values above 0.5 in pairwise comparisons, which indicates a considerable degree of genetic isolation among the suggested species. We also found low climatic niche overlap among all taxa, suggesting that each group occurs at specific conditions of temperature, precipitation and elevation. We propose that H. americana comprises two cryptic species, which may be reproductively isolated by ecological barriers related to niche divergence, since the morphological variation is minimal and, therefore, mechanical barriers are probably less effective compared to other related species such as H. calverti.


Assuntos
Especiação Genética , Odonatos , Humanos , Animais , Filogenia , Genoma , Genômica
2.
Horm Behav ; 164: 105593, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909429

RESUMO

Autism Spectrum Disorder (ASD) is characterized by differences in social communication and interaction, as well as areas of focused interests and/or repetitive behaviors. Recent studies have highlighted a higher prevalence of endocrine and reproductive disturbances among females on the autism spectrum, hinting at potential disruptions within the hypothalamus-pituitary-ovary (HPO) axis. This research aims to explore the reproductive health disparities in ASD using an animal model of autism, the C58/J inbred mouse strain, with a focus on reproductive performance and hormonal profiles compared to the C57BL/6J control strain. Our findings revealed that the estrous cycle in C58/J females is disrupted, as evidenced by a lower frequency of complete cycles and a lack of cyclical release of estradiol and progesterone compared to control mice. C58/J females also exhibited poor performance in several reproductive parameters, including reproductive lifespan and fertility index. Furthermore, estrogen receptor alpha content showed a marked decrease in the hypothalamus of C58/J mice. These alterations in the estrous cycle, hormonal imbalances, and reduced reproductive function imply dysregulation in the HPO axis. Additionally, our in-silico study identified a group of genes involved in infertility carrying single-nucleotide polymorphisms (SNPs) in the C58/J strain, which also have human orthologs associated with autism. These findings could offer valuable insights into the molecular underpinnings of neuroendocrine axis disruption and reproductive issues observed in ASD.

3.
J Hered ; 115(1): 103-111, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-37988159

RESUMO

Smoky rubyspot damselflies (Hetaerina titia Drury, 1773) are one of the most commonly encountered odonates along streams and rivers on both slopes of Central America and the Atlantic drainages in the United States and southern Canada. Owing to their highly variable wing pigmentation, they have become a model system for studying sexual selection and interspecific behavioral interference. Here, we sequence and assemble the genome of a female smoky rubyspot. Of the primary assembly (i.e. the principle pseudohaplotype), 98.8% is made up of 12 chromosomal pseudomolecules (2N = 22A + X). There are 75 scaffolds in total, an N50 of 120 Mb, a contig-N50 of 0.64 Mb, and a high arthropod BUSCO score [C: 97.6% (S: 97.3%, D: 0.3%), F: 0.8%, M: 1.6%]. We then compare our assembly to that of the blue-tailed damselfly genome (Ischnura elegans), the most complete damselfly assembly to date, and a recently published assembly for an American rubyspot damselfly (Hetaerina americana). Collectively, these resources make Hetaerina a genome-enabled genus for further studies of the ecological and evolutionary forces shaping biological diversity.


Assuntos
Odonatos , Animais , Feminino , Odonatos/genética , Fumaça , Evolução Biológica , Pigmentação , Cromossomos/genética
4.
J Public Health Manag Pract ; 28(1): 50-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34797241

RESUMO

CONTEXT: Coronavirus disease 2019 (COVID-19) incidence rates are 2- to 5-fold higher among persons incarcerated in the United States than in the general population. PROGRAM OR POLICY: We describe an outbreak investigation of COVID-19 at a jail (jail A) in Alameda County during March 2020-March 2021. IMPLEMENTATION: To prevent COVID-19 cases among incarcerated persons and employees, staff at jail A and the county public health department worked to develop and recommend infection control measures implemented by jail A including, but not limited to, face covering use among incarcerated persons and staff; cohorting incarcerated persons at a higher risk of severe COVID-19 in dedicated housing units; quarantining all newly detained individuals for 14 days; and offering testing for all symptomatic incarcerated persons, newly incarcerated persons at day 2 and day 10, and all persons who resided in a housing unit where a COVID-19 case was detected. EVALUATION: A total of 571 COVID-19 cases were detected among incarcerated persons at jail A during March 2020-March 2021, which represented a total incidence of 280 per 1000 population, 5 times higher than the rate in Alameda County. Of the 571 cases among incarcerated persons, 557 (98%) were male; 415 (73%) were aged 18 to 40 years; 249 (44%) were Latino; and 180 (32%) were African American; 354 (62%) were not symptomatic; and 220 (39%) had no comorbidities. Less than 2% of infected incarcerated persons were hospitalized, and no deaths were reported. DISCUSSION: COVID-19 disproportionately impacted persons incarcerated at jail A, with higher numbers among Latinos and African Americans. Implementation of COVID-19 infection control and testing measures, and collaboration between public health, law enforcement, and health care providers may have, in part, led to reductions in morbidity and mortality associated with COVID-19 at jail A.


Assuntos
COVID-19 , Prisões Locais , California/epidemiologia , Humanos , Masculino , Prisões , Quarentena , SARS-CoV-2 , Estados Unidos
5.
Appl Environ Microbiol ; 85(6)2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30635383

RESUMO

Efficient microbial conversion of lignocellulose into valuable products is often hindered by the presence of furfural, a dehydration product of pentoses in hemicellulose sugar syrups derived from woody biomass. For a cost-effective lignocellulose microbial conversion, robust biocatalysts are needed that can tolerate toxic inhibitors while maintaining optimal metabolic activities. A comprehensive plasmid-based library encoding native multidrug resistance (MDR) efflux pumps, porins, and select exporters from Escherichia coli was screened for furfural tolerance in an ethanologenic E. coli strain. Small multidrug resistance (SMR) pumps, such as SugE and MdtJI, as well as a lactate/glycolate:H+ symporter, LldP, conferred furfural tolerance in liquid culture tests. Expression of the SMR pump potentially increased furfural efflux and cellular viability upon furfural assault, suggesting novel activities for SMR pumps as furfural efflux proteins. Furthermore, induced expression of mdtJI enhanced ethanol fermentative production of LY180 in the presence of furfural or 5-hydroxymethylfurfural, further demonstrating the applications of SMR pumps. This work describes an effective approach to identify useful efflux systems with desired activities for nonnative toxic chemicals and provides a platform to further enhance furfural efflux by protein engineering and mutagenesis.IMPORTANCE Lignocellulosic biomass, especially agricultural residues, represents an important potential feedstock for microbial production of renewable fuels and chemicals. During the deconstruction of hemicellulose by thermochemical processes, side products that inhibit cell growth and production, such as furan aldehydes, are generated, limiting cost-effective lignocellulose conversion. Here, we developed a new approach to increase cellular tolerance by expressing multidrug resistance (MDR) pumps with putative efflux activities for furan aldehydes. The developed plasmid library and screening methods may facilitate new discoveries of MDR pumps for diverse toxic chemicals important for microbial conversion.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Etanol/metabolismo , Furaldeído/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Bioprospecção , Proteínas de Escherichia coli/genética , Fermentação , Furaldeído/análogos & derivados , Engenharia Genética , Lignina/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética
6.
Mol Phylogenet Evol ; 139: 106536, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31212083

RESUMO

Analyzing the magnitude and distribution of genetic variation within and among populations allows for hypothesis testing about historical demographic size changes, secondary contacts, refugia, and speciation patterns. Species distribution and genetic structure are greatly influenced by the complex life cycle and behavior of odonates. Hetaerina americana has been widely used as a model system in behavioral studies, but its population genetic structure has not been analyzed, except for a single study that included only three populations but identified the presence of markedly differentiated genetic groups, suggesting the existence of cryptic species. Here, we tested this hypothesis by assessing throughout the distribution range of H. americana the patterns of genetic and morphological variation in the male caudal appendages, due to the great importance of these structures in mate recognition. As molecular markers we used sequences of the mitochondrial cytochrome oxidase I (COI) gene and the nuclear internal transcribed spacer (ITS) region, as well as six nuclear microsatellites. We found very high population genetic differentiation (ΦST > 0.51) in the three sets of markers but with strong mitonuclear discordance. A neutrality test suggested that the mitochondrial genome might be under purifying selection in association to climatic variables (temperature seasonality). The assignment of individuals to nuclear genetic groups showed little admixture and complete congruence with morphological differentiation in the male caudal appendages. Hence, the results suggest that H. americana represents at least two different cryptic species which are isolated reproductively.


Assuntos
Evolução Biológica , Especiação Genética , Odonatos/fisiologia , Animais , Sequência de Bases , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Variação Genética , Genoma Mitocondrial , Haplótipos/genética , Masculino , Repetições de Microssatélites/genética , Odonatos/genética , Filogenia
7.
Appl Microbiol Biotechnol ; 103(21-22): 9001-9011, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31641813

RESUMO

Optimization of export mechanisms for valuable extracellular products is important for the development of efficient microbial production processes. Identification of the relevant export mechanism is the prerequisite step for product export optimization. In this work, we identified transporters involved in malate export in an engineered L-malate-producing Escherichia coli strain using cheminformatics-guided genetics tests. Among all short-chain di- or tricarboxylates with known transporters in E. coli, citrate, tartrate, and succinate are most chemically similar to malate as estimated by their molecular signatures. Inactivation of three previously reported transporters for succinate, tartrate, and citrate, DcuA, TtdT, and CitT, respectively, dramatically decreased malate production and fermentative growth, suggesting that these transporters have substrate promiscuity for different short-chain organic acids and constitute the major malate export system in E. coli. Malate export deficiency led to an increase in cell sizes and accumulation of intracellular metabolites related to malate metabolism.


Assuntos
Transporte Biológico/genética , Proteínas de Transporte/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Malatos/metabolismo , Proteínas de Bactérias/genética , Ácido Cítrico/metabolismo , Transportadores de Ácidos Dicarboxílicos/genética , Proteínas de Escherichia coli/genética , Fermentação/genética , Engenharia Genética , Transportadores de Ânions Orgânicos/genética , Ácido Succínico/metabolismo , Tartaratos/metabolismo
8.
Glob Chang Biol ; 23(3): 1075-1084, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27558698

RESUMO

Although observations suggest the potential for phenotypic plasticity to allow adaptive responses to climate change, few experiments have assessed that potential. Modeling suggests that Sceloporus tristichus lizards will need increased nest depth, shade cover, or embryonic thermal tolerance to avoid reproductive failure resulting from climate change. To test for such plasticity, we experimentally examined how maternal temperatures affect nesting behavior and embryonic thermal sensitivity. The temperature regime that females experienced while gravid did not affect nesting behavior, but warmer temperatures at the time of nesting reduced nest depth. Additionally, embryos from heat-stressed mothers displayed increased sensitivity to high-temperature exposure. Simulations suggest that critically low temperatures, rather than high temperatures, historically limit development of our study population. Thus, the plasticity needed to buffer this population has not been under selection. Plasticity will likely fail to compensate for ongoing climate change when such change results in novel stressors.


Assuntos
Mudança Climática , Lagartos/fisiologia , Comportamento de Nidação , Adaptação Fisiológica , Animais , Clima , Feminino , Temperatura
9.
Sci Rep ; 12(1): 10888, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764791

RESUMO

Incomplete premating barriers in closely related species may result in reproductive interference. This process has different fitness consequences and can lead to three scenarios: niche segregation, sexual exclusion, or reproductive character displacement. In morphologically cryptic species, isolation barriers can be difficult to recognize. Here, we analyzed the morphological, behavioral, and genetic differences between two sympatric cryptic species of the genus Hetaerina to determine the characters that contribute the most to reproductive isolation and the effect of the high rates of behavior interference between the species. We found complete genetic isolation and significant differences in the morphometry of caudal appendages and wing shape, as well as body size variation between species. In contrast, we did not find clear differences in the coloration of the wing spot and observed high rates of interspecific aggression. Our results suggest that divergence in the shape of the caudal appendages is the principal pre-mating barrier that prevents interspecific mating. Moreover, a scenario of character displacement on body size was found. Nevertheless, size could play an important role in both inter- and intrasexual interactions and, therefore, we cannot differentiate if it has resulted from reproductive or aggressive interference.


Assuntos
Odonatos , Isolamento Reprodutivo , Animais , Evolução Biológica , Especificidade da Espécie , Asas de Animais/anatomia & histologia
10.
Zootaxa ; 4766(3): zootaxa.4766.3.7, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33056594

RESUMO

Hetaerina americana Fabricius, 1798 has a long and irresolute taxonomic history. Several synonyms have been suggested (H. californica Hagen in Selys-Longchamps, 1859, H. basalis Hagen in Selys-Longchamps, 1859, H. texana Walsh, 1863, H. scelerata Walsh, 1863, etc.), related to the variation in the size of the wing spots as well as to the morphology of the male cerci. However, Calvert (1901) suggested that H. americana represents one variable species. Nevertheless, Vega-Sánchez et al. (2019) through a genetic and morphological analysis presented evidence to propose that H. americana represents a species complex. In the present work, we describe a new species that belongs to this complex: H. calverti sp. nov. The morphological characteristics by which males and females of H. calverti differ from H. americana are highlighted. The most important character for the differentiation of males is the shape of the cerci and the size of the individuals (when the two species are in sympatry). In females, the main differences are in the shape of the intersternites and the medio-dorsal carina of the last segment of the abdomen. Some generalities about the biology of the species are presented, including geographical distribution patterns and genetic divergence data. [urn:lsid:zoobank.org:act:F5C329AE-7A00-4979-8A0D-A13D869E54B1].


Assuntos
Odonatos , Animais , Feminino , Deriva Genética , Masculino , Estados Unidos , Asas de Animais
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