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1.
Semin Cell Dev Biol ; 154(Pt A): 35-47, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37438210

RESUMO

Neurons are remarkably long-lived, non-dividing cells that must maintain their functional features (e.g., electrical properties, chemical signaling) for extended periods of time - decades in humans. How neurons accomplish this incredible feat is poorly understood. Here, we review recent advances, primarily in the nematode C. elegans, that have enhanced our understanding of the molecular mechanisms that enable post-mitotic neurons to maintain their functionality across different life stages. We begin with "terminal selectors" - transcription factors necessary for the establishment and maintenance of neuronal identity. We highlight new findings on five terminal selectors (CHE-1 [Glass], UNC-3 [Collier/Ebf1-4], LIN-39 [Scr/Dfd/Hox4-5], UNC-86 [Acj6/Brn3a-c], AST-1 [Etv1/ER81]) from different transcription factor families (ZNF, COE, HOX, POU, ETS). We compare the functions of these factors in specific neuron types of C. elegans with the actions of their orthologs in other invertebrate (D. melanogaster) and vertebrate (M. musculus) systems, highlighting remarkable functional conservation. Finally, we reflect on recent findings implicating chromatin-modifying proteins, such as histone methyltransferases and Polycomb proteins, in the control of neuronal terminal identity. Altogether, these new studies on transcription factors and chromatin modifiers not only shed light on the fundamental problem of neuronal identity maintenance, but also outline mechanistic principles of gene regulation that may operate in other long-lived, post-mitotic cell types.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Cromatina/genética , Cromatina/metabolismo , Diferenciação Celular , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Drosophila melanogaster/metabolismo , Neurônios/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
2.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39101589

RESUMO

The mouse serves as a mammalian model for understanding the nature of variation from new mutations, a question that has both evolutionary and medical significance. Previous studies suggest that the rate of single-nucleotide mutations (SNMs) in mice is ∼50% of that in humans. However, information largely comes from studies involving the C57BL/6 strain, and there is little information from other mouse strains. Here, we study the mutations that accumulated in 59 mouse lines derived from four inbred strains that are commonly used in genetics and clinical research (BALB/cAnNRj, C57BL/6JRj, C3H/HeNRj, and FVB/NRj), maintained for eight to nine generations by brother-sister mating. By analyzing Illumina whole-genome sequencing data, we estimate that the average rate of new SNMs in mice is ∼µ = 6.7 × 10-9. However, there is substantial variation in the spectrum of SNMs among strains, so the burden from new mutations also varies among strains. For example, the FVB strain has a spectrum that is markedly skewed toward C→A transversions and is likely to experience a higher deleterious load than other strains, due to an increased frequency of nonsense mutations in glutamic acid codons. Finally, we observe substantial variation in the rate of new SNMs among DNA sequence contexts, CpG sites, and their adjacent nucleotides playing an important role.


Assuntos
Camundongos Endogâmicos , Animais , Camundongos , Camundongos Endogâmicos/genética , Mutação , Camundongos Endogâmicos C57BL
3.
Mol Biol Evol ; 41(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38513632

RESUMO

Chromosomal fusions represent one of the most common types of chromosomal rearrangements found in nature. Yet, their role in shaping the genomic landscape of recombination and hence genome evolution remains largely unexplored. Here, we take advantage of wild mice populations with chromosomal fusions to evaluate the effect of this type of structural variant on genomic landscapes of recombination and divergence. To this aim, we combined cytological analysis of meiotic crossovers in primary spermatocytes with inferred analysis of recombination rates based on linkage disequilibrium using single nucleotide polymorphisms. Our results suggest the presence of a combined effect of Robertsonian fusions and Prdm9 allelic background, a gene involved in the formation of meiotic double strand breaks and postzygotic reproductive isolation, in reshaping genomic landscapes of recombination. We detected a chromosomal redistribution of meiotic recombination toward telomeric regions in metacentric chromosomes in mice with Robertsonian fusions when compared to nonfused mice. This repatterning was accompanied by increased levels of crossover interference and reduced levels of estimated recombination rates between populations, together with high levels of genomic divergence. Interestingly, we detected that Prdm9 allelic background was a major determinant of recombination rates at the population level, whereas Robertsonian fusions showed limited effects, restricted to centromeric regions of fused chromosomes. Altogether, our results provide new insights into the effect of Robertsonian fusions and Prdm9 background on meiotic recombination.


Assuntos
Cromossomos , Genômica , Masculino , Animais , Camundongos , Alelos
4.
Mol Biol Evol ; 40(1)2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36508360

RESUMO

Meiotic recombination is an important evolutionary force and an essential meiotic process. In many species, recombination events concentrate into hotspots defined by the site-specific binding of PRMD9. Rapid evolution of Prdm9's zinc finger DNA-binding array leads to remarkably abrupt shifts in the genomic distribution of hotspots between species, but the question of how Prdm9 allelic variation shapes the landscape of recombination between populations remains less well understood. Wild house mice (Mus musculus) harbor exceptional Prdm9 diversity, with >150 alleles identified to date, and pose a particularly powerful system for addressing this open question. We employed a coalescent-based approach to construct broad- and fine-scale sex-averaged recombination maps from contemporary patterns of linkage disequilibrium in nine geographically isolated wild house mouse populations, including multiple populations from each of three subspecies. Comparing maps between wild mouse populations and subspecies reveals several themes. First, we report weak fine- and broad-scale recombination map conservation across subspecies and populations, with genetic divergence offering no clear prediction for recombination map divergence. Second, most hotspots are unique to one population, an outcome consistent with minimal sharing of Prdm9 alleles between surveyed populations. Finally, by contrasting aggregate hotspot activity on the X versus autosomes, we uncover evidence for population-specific differences in the degree and direction of sex dimorphism for recombination. Overall, our findings illuminate the variability of both the broad- and fine-scale recombination landscape in M. musculus and underscore the functional impact of Prdm9 allelic variation in wild mouse populations.


Assuntos
Evolução Molecular , Variação Genética , Histona-Lisina N-Metiltransferase , Camundongos , Animais , Camundongos/genética , Cromossomos/genética , Genoma , Histona-Lisina N-Metiltransferase/genética
5.
Proc Biol Sci ; 291(2019): 20240099, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38503332

RESUMO

In many species, establishing and maintaining a territory is critical to survival and reproduction, and an animal's ability to do so is strongly influenced by the presence and density of competitors. Here we manipulate social conditions to study the alternative reproductive tactics displayed by genetically identical, age-matched laboratory mice competing for territories under ecologically realistic social environmental conditions. We introduced adult males and females of the laboratory mouse strain C57BL/6J into a large, outdoor field enclosure containing defendable resource zones under one of two social conditions. We first created a low-density social environment, such that the number of available territories exceeded the number of males. After males established stable territories, we introduced a pulse of intruder males and observed the resulting defensive and invasive tactics employed. In response to this change in social environment, males with large territories invested more in patrolling but were less effective at excluding intruder males as compared with males with small territories. Intruding males failed to establish territories and displayed an alternative tactic featuring greater exploration as compared with genetically identical territorial males. Alternative tactics did not lead to equal reproductive success-males that acquired territories experienced greater survival and had greater access to females.


Assuntos
Comportamento Sexual Animal , Condições Sociais , Masculino , Feminino , Camundongos , Animais , Comportamento Sexual Animal/fisiologia , Camundongos Endogâmicos C57BL , Territorialidade , Reprodução/fisiologia
6.
Mol Ecol ; 33(1): e17192, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37933543

RESUMO

The question of how interactions between the gut microbiome and vertebrate hosts contribute to host adaptation and speciation is one of the major problems in current evolutionary research. Using bacteriome and mycobiome metabarcoding, we examined how these two components of the gut microbiota vary with the degree of host admixture in secondary contact between two house mouse subspecies (Mus musculus musculus and M. m. domesticus). We used a large data set collected at two replicates of the hybrid zone and model-based statistical analyses to ensure the robustness of our results. Assuming that the microbiota of wild hosts suffers from spatial autocorrelation, we directly compared the results of statistical models that were spatially naive with those that accounted for spatial autocorrelation. We showed that neglecting spatial autocorrelation can strongly affect the results and lead to misleading conclusions. The spatial analyses showed little difference between subspecies, both in microbiome composition and in individual bacterial lineages. Similarly, the degree of admixture had minimal effects on the gut bacteriome and mycobiome and was caused by changes in a few microbial lineages that correspond to the common symbionts of free-living house mice. In contrast to previous studies, these data do not support the hypothesis that the microbiota plays an important role in host reproductive isolation in this particular model system.


Assuntos
Microbioma Gastrointestinal , Microbiota , Camundongos , Animais , Microbioma Gastrointestinal/genética , Evolução Biológica , Isolamento Reprodutivo
7.
Mol Ecol ; 33(8): e17330, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561950

RESUMO

Age is a key parameter in population ecology, with a myriad of biological processes changing with age as organisms develop in early life then later senesce. As age is often hard to accurately measure with non-lethal methods, epigenetic methods of age estimation (epigenetic clocks) have become a popular tool in animal ecology and are often developed or calibrated using captive animals of known age. However, studies typically rely on invasive blood or tissue samples, which limit their application in more sensitive or elusive species. Moreover, few studies have directly assessed how methylation patterns and epigenetic age estimates compare across environmental contexts (e.g. captive or laboratory-based vs. wild animals). Here, we built a targeted epigenetic clock from laboratory house mice (strain C57BL/6, Mus musculus) using DNA from non-invasive faecal samples, and then used it to estimate age in a population of wild mice (Mus musculus domesticus) of unknown age. This laboratory mouse-derived epigenetic clock accurately predicted adult wild mice to be older than juveniles and showed that wild mice typically increased in epigenetic age over time, but with wide variation in epigenetic ageing rate among individuals. Our results also suggested that, for a given body mass, wild mice had higher methylation across targeted CpG sites than laboratory mice (and consistently higher epigenetic age estimates as a result), even among the smallest, juvenile mice. This suggests wild and laboratory mice may display different CpG methylation levels from very early in life and indicates caution is needed when developing epigenetic clocks on laboratory animals and applying them in the wild.


Assuntos
Envelhecimento , Metilação de DNA , Camundongos , Animais , Metilação de DNA/genética , Camundongos Endogâmicos C57BL , Envelhecimento/genética , Animais Selvagens/genética , Epigênese Genética
8.
J Anat ; 244(5): 722-738, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38214368

RESUMO

The semicircular canals of the inner ear are involved in balance and velocity control. Being crucial to ensure efficient mobility, their morphology exhibits an evolutionary conservatism attributed to stabilizing selection. Release of selection in slow-moving animals has been argued to lead to morphological divergence and increased inter-individual variation. In its natural habitat, the house mouse Mus musculus moves in a tridimensional space where efficient balance is required. In contrast, laboratory mice in standard cages are severely restricted in their ability to move, which possibly reduces selection on the inner ear morphology. This effect was tested by comparing four groups of mice: several populations of wild mice trapped in commensal habitats in France; their second-generation laboratory offspring, to assess plastic effects related to breeding conditions; a standard laboratory strain (Swiss) that evolved for many generations in a regime of mobility reduction; and hybrids between wild offspring and Swiss mice. The morphology of the semicircular canals was quantified using a set of 3D landmarks and semi-landmarks analyzed using geometric morphometric protocols. Levels of inter-population, inter-individual (disparity) and intra-individual (asymmetry) variation were compared. All wild mice shared a similar inner ear morphology, in contrast to the important divergence of the Swiss strain. The release of selection in the laboratory strain obviously allowed for an important and rapid drift in the otherwise conserved structure. Shared traits between the inner ear of the lab strain and domestic pigs suggested a common response to mobility reduction in captivity. The lab-bred offspring of wild mice also differed from their wild relatives, suggesting plastic response related to maternal locomotory behavior, since inner ear morphology matures before birth in mammals. The signature observed in lab-bred wild mice and the lab strain was however not congruent, suggesting that plasticity did not participate to the divergence of the laboratory strain. However, contrary to the expectation, wild mice displayed slightly higher levels of inter-individual variation than laboratory mice, possibly due to the higher levels of genetic variance within and among wild populations compared to the lab strain. Differences in fluctuating asymmetry levels were detected, with the laboratory strain occasionally displaying higher asymmetry scores than its wild relatives. This suggests that there may indeed be a release of selection and/or a decrease in developmental stability in the laboratory strain.


Assuntos
Evolução Biológica , Canais Semicirculares , Animais , Camundongos , Canais Semicirculares/anatomia & histologia , Mamíferos , França
9.
J Exp Biol ; 227(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38873751

RESUMO

The influence of light spectral properties on circadian rhythms is of substantial interest to laboratory-based investigation of the circadian system and to field-based understanding of the effects of artificial light at night. The trade-offs between intensity and spectrum regarding masking behaviors are largely unknown, even for well-studied organisms. We used a custom LED illumination system to document the response of wild-type house mice (Mus musculus) to 1-h nocturnal exposure of all combinations of four intensity levels (0.01, 0.5, 5 and 50 lx) and three correlated color temperatures (CCT; 1750, 1950 and 3000 K). Higher intensities of light (50 lx) suppressed cage activity substantially, and consistently more for the higher CCT light (91% for 3000 K, 53% for 1750 K). At the lowest intensity (0.01 lx), mean activity was increased, with the greatest increases for the lowest CCT (12.3% increase at 1750 K, 3% increase at 3000 K). Multiple linear regression confirmed the influence of both CCT and intensity on changes in activity, with the scaled effect size of intensity 3.6 times greater than that of CCT. Activity suppression was significantly lower for male than for female mice. Assessment of light-evoked cFos expression in the suprachiasmatic nucleus at 50 lx showed no significant difference between high and low CCT exposure. The significant differences by spectral composition illustrate a need to account for light spectrum in circadian studies of behavior, and confirm that spectral controls can mitigate some, but certainly not all, of the effects of light pollution on species in the wild.


Assuntos
Ritmo Circadiano , Luz , Iluminação , Animais , Camundongos/fisiologia , Masculino , Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos da radiação , Feminino , Comportamento Animal/efeitos da radiação , Comportamento Animal/fisiologia , Atividade Motora/efeitos da radiação , Temperatura
10.
J Exp Biol ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39206582

RESUMO

Exposure to winter cold causes an increase in energy demands to meet the challenge of thermoregulation. In small rodents, this increase in cardiac output leads to a profound cardiac hypertrophy, 2-3x that typically seen with exercise training. The nature of this hypertrophy and its relevance to winter mortality remains unclear. Our goal was to characterize cold-induced cardiac hypertrophy and to assess its similarity to either exercise-induced (physiological) hypertrophy or the pathological hypertrophy of hypertension. We hypothesized that cold-induced hypertrophy will most closely resemble exercise-induced hypertrophy, but be another unique pathway for physiological cardiac growth. We found that cold-induced hypertrophy was largely reversed after return to warm temperatures. Further, metabolic rates were elevated while gene expression and mitochondrial enzyme activities indicative of pathology were absent. A gene expression panel comparing hearts of exercised and cold exposed mice further suggests that these activities are similar, although not identical. In conclusion, we found that chronic cold led to a phenotype that most closely resembled physiological hypertrophy, with enhanced metabolic rate, without induction of fetal genes , but with decreased expression of genes associated with fatty acid oxidation, suggesting that heart failure is not a cause of winter mortality in small rodents and identifying a novel approach for the study of cardiac growth.

11.
Adv Exp Med Biol ; 1441: 435-458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38884724

RESUMO

Over the last few decades, the study of congenital heart disease (CHD) has benefited from various model systems and the development of molecular biological techniques enabling the analysis of single gene as well as global effects. In this chapter, we first describe different models including CHD patients and their families, animal models ranging from invertebrates to mammals, and various cell culture systems. Moreover, techniques to experimentally manipulate these models are discussed. Second, we introduce cardiac phenotyping technologies comprising the analysis of mouse and cell culture models, live imaging of cardiogenesis, and histological methods for fixed hearts. Finally, the most important and latest molecular biotechniques are described. These include genotyping technologies, different applications of next-generation sequencing, and the analysis of transcriptome, epigenome, proteome, and metabolome. In summary, the models and technologies presented in this chapter are essential to study the function and development of the heart and to understand the molecular pathways underlying CHD.


Assuntos
Cardiopatias Congênitas , Animais , Humanos , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/metabolismo , Modelos Animais de Doenças , Camundongos , Fenótipo , Sequenciamento de Nucleotídeos em Larga Escala , Técnicas de Cultura de Células/métodos
12.
Parasitol Res ; 123(6): 237, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856825

RESUMO

Mastophorus muris (Gmelin, 1790) is a globally distributed parasitic nematode of broad range mammals. The taxonomy within the genus Mastophorus and the cryptic diversity among the genus are controversial among taxonomists. This study provides a detailed morphological description of M. muris from Mus musculus combined with a molecular phylogenetic approach. Moreover, descriptions and molecular data of M. muris from non-Mus rodents and wildcats complement our findings and together provide new insights into their taxonomy. The analysis of M. muris was based on light microscopy and scanning electron microscopy. The morphological description focused on the dentition pattern of the two trilobed pseudolabia. Additionally, we described the position of the vulva, arrangement of caudal pairs of papillae, spicules and measured specimens from both sexes and the eggs. For the molecular phylogenetic approach, we amplified the small subunit ribosomal RNA gene and the internal transcribed spacer, and the cytochrome c oxidase subunit 1. Mastophorus morphotypes based on dentition patterns and phylogenetic clustering indicate a subdivision of the genus in agreement with their host. We recognize two groups without a change to formal taxonomy: One group including those specimens infecting Mus musculus, and the second group including organisms infecting non-Mus rodents. Our genetic and morphological data shed light into the cryptic diversity within the genus Mastopohorus. We identified two host-associated groups of M. muris. The described morphotypes and genotypes of M. muris allow a consistent distinction between host-associated parasites.


Assuntos
Microscopia Eletrônica de Varredura , Filogenia , Animais , Feminino , Masculino , Camundongos , Spiruroidea/classificação , Spiruroidea/genética , Spiruroidea/anatomia & histologia , Spiruroidea/isolamento & purificação , Spiruroidea/ultraestrutura , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Análise de Sequência de DNA , Microscopia , DNA de Helmintos/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Análise por Conglomerados , Dados de Sequência Molecular
13.
Dev Dyn ; 252(9): 1180-1188, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37212424

RESUMO

BACKGROUND: Tendons and ligaments attach to bone are essential for joint mobility and stability in vertebrates. Tendon and ligament attachments (ie, entheses) are found at bony protrusions (ie, eminences), and the shape and size of these protrusions depend on both mechanical forces and cellular cues during growth. Tendon eminences also contribute to mechanical leverage for skeletal muscle. Fibroblast growth factor receptor (FGFR) signaling plays a critical role in bone development, and Fgfr1 and Fgfr2 are highly expressed in the perichondrium and periosteum of bone where entheses can be found. RESULTS AND CONCLUSIONS: We used transgenic mice for combinatorial knockout of Fgfr1 and/or Fgfr2 in tendon/attachment progenitors (ScxCre) and measured eminence size and shape. Conditional deletion of both, but not individual, Fgfr1 and Fgfr2 in Scx progenitors led to enlarged eminences in the postnatal skeleton and shortening of long bones. In addition, Fgfr1/Fgfr2 double conditional knockout mice had more variation collagen fibril size in tendon, decreased tibial slope, and increased cell death at ligament attachments. These findings identify a role for FGFR signaling in regulating growth and maintenance of tendon/ligament attachments and the size and shape of bony eminences.


Assuntos
Osso e Ossos , Tendões , Animais , Camundongos , Morte Celular/genética , Camundongos Knockout , Camundongos Transgênicos , Células-Tronco , Tendões/metabolismo
14.
Am Nat ; 201(2): 256-268, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36724459

RESUMO

AbstractFemale reproductive success is often limited by access to resources, and this can lead to social competition both within and between kin groups. Theory predicts that both resource availability and relatedness should influence the fitness consequences of social competition. However, testing key predictions requires differentiating the effects of these two factors. Here, we achieve this experimentally by manipulating the social environment of house mice, a facultative communal breeding species with known kin discrimination ability. This allows us to investigate (1) the reproductive costs of defending a limited resource in response to cues of social competition and (2) whether such costs, or their potential mitigation via cooperative behavior, are influenced by the relatedness of competitors. Our results support the hypothesis that resource defense can be costly for females, potentially trading off against maternal investment. When the availability of protected nest sites was limited, subjects (1) were more active, (2) responded more strongly to simulated territory intrusions via competitive signaling, and (3) produced smaller weaned offspring. However, we found no evidence that the propensity for kin to cooperate was influenced by the relatedness of rivals. Communal breeding between sisters occurred independently of the relatedness of competitors and communally breeding sisters weaned fewer offspring when competing with unrelated females, despite our study being designed to prevent infanticide between kin groups. Our findings thus demonstrate that female competition has fitness costs and that associating with kin is beneficial to avoid negative fitness consequences of competing with nonkin, in addition to more widely recognized kin-selected benefits.


Assuntos
Comportamento Cooperativo , Comportamento Social , Animais , Camundongos , Feminino , Humanos , Meio Social , Irmãos , Reprodução
15.
Proc Biol Sci ; 290(1997): 20222452, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37122257

RESUMO

Studies of socially mediated phenotypic plasticity have demonstrated adaptive male responses to the 'competitive' environment. Despite this, whether variation in the paternal social environment also influences offspring reproductive potential in an intergenerational context has not yet been examined. Here, we studied the descendants of wild-caught house mice, a destructive pest species worldwide, to address this knowledge gap. We analysed traits that define a 'competitive' phenotype in the sons of males (sires) that had been exposed to either a high-male density (competitive) or high-female density (non-competitive) environment. We report disparate reproductive strategies among the sires: high-male density led to a phenotype geared for competition, while high-female density led to a phenotype that would facilitate elevated mating frequency. Moreover, we found that the competitive responses of sires persisted in the subsequent generation, with the sons of males reared under competition having elevated sperm quality. As all sons were reared under common-garden conditions, variation in their reproductive phenotypes could only have arisen via nongenetic inheritance. We discuss our results in relation to the adaptive advantage of preparing sons for sperm competition and suggest that intergenerational plasticity is a previously unconsidered aspect in invasive mammal fertility control.


Assuntos
Sêmen , Espermatozoides , Animais , Camundongos , Masculino , Feminino , Espermatozoides/fisiologia , Reprodução , Adaptação Fisiológica , Mamíferos , Comportamento Sexual Animal
16.
Anim Cogn ; 26(3): 997-1009, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36737560

RESUMO

Individual variation in cognition is being increasingly recognized as an important evolutionary force but contradictory results so far hamper a general understanding of consistency and association with other behaviors. Partly, this might be caused by external factors imposed by the design. Stress, for example, is known to influence cognition, with mild stress improving learning abilities, while strong or chronic stress impairs them. Also, there might be intraspecific variation in how stressful a given situation is perceived. We investigated two personality traits (stress coping and voluntary exploration), spatial learning with two mazes, and problem-solving in low- and high-stress tests with a group of 30 female wild mice (Mus musculus domesticus). For each test, perceived stress was assessed by measuring body temperature change with infrared thermography, a new non-invasive method that measures skin temperature as a proxy of changes in the sympathetic system activity. While spatial learning and problem-solving were found to be repeatable traits in mice in earlier studies, none of the learning measures were significantly repeatable between the two stress conditions in our study, indicating that the stress level impacts learning. We found correlations between learning and personality traits; however, they differed between the two stress conditions and between the cognitive tasks, suggesting that different mechanisms underlie these processes. These findings could explain some of the contradictory findings in the literature and argue for very careful design of cognitive test setups to draw evolutionary implications.


Assuntos
Cognição , Resolução de Problemas , Animais , Camundongos , Feminino , Aprendizagem Espacial , Adaptação Psicológica , Personalidade
17.
Chromosome Res ; 30(2-3): 165-186, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35829972

RESUMO

Meiotic drive occurs when one allele at a heterozygous site cheats its way into a disproportionate share of functional gametes, violating Mendel's law of equal segregation. This genetic conflict typically imposes a fitness cost to individuals, often by disrupting the process of gametogenesis. The evolutionary impact of meiotic drive is substantial, and the phenomenon has been associated with infertility and reproductive isolation in a wide range of organisms. However, cases of meiotic drive in humans remain elusive, a finding that likely reflects the inherent challenges of detecting drive in our species rather than unique features of human genome biology. Here, we make the case that house mice (Mus musculus) present a powerful model system to investigate the mechanisms and consequences of meiotic drive and facilitate translational inferences about the scope and potential mechanisms of drive in humans. We first detail how different house mouse resources have been harnessed to identify cases of meiotic drive and the underlying mechanisms utilized to override Mendel's rules of inheritance. We then summarize the current state of knowledge of meiotic drive in the mouse genome. We profile known mechanisms leading to transmission bias at several established drive elements. We discuss how a detailed understanding of meiotic drive in mice can steer the search for drive elements in our own species. Lastly, we conclude with a prospective look into how new technologies and molecular tools can help resolve lingering mysteries about the prevalence and mechanisms of selfish DNA transmission in mammals.


Assuntos
Meiose , Sequências Repetitivas de Ácido Nucleico , Alelos , Animais , Biologia , Humanos , Mamíferos/genética , Meiose/genética , Camundongos , Estudos Prospectivos
18.
Mol Ther ; 30(4): 1661-1674, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-34400330

RESUMO

Emerging clinical data show that three ceramide molecules, Cer d18:1/16:0, Cer d18:1/24:1, and Cer d18:1/24:0, are biomarkers of a fatal outcome in patients with cardiovascular disease. This finding raises basic questions about their metabolic origin, their contribution to disease pathogenesis, and the utility of targeting the underlying enzymatic machinery for treatment of cardiometabolic disorders. Here, we outline the development of a potent N-acetylgalactosamine-conjugated antisense oligonucleotide engineered to silence ceramide synthase 2 specifically in hepatocytes in vivo. We demonstrate that this compound reduces the ceramide synthase 2 mRNA level and that this translates into efficient lowering of protein expression and activity as well as Cer d18:1/24:1 and Cer d18:1/24:0 levels in liver. Intriguingly, we discover that the hepatocyte-specific antisense oligonucleotide also triggers a parallel modulation of blood plasma ceramides, revealing that the biomarkers predictive of cardiovascular death are governed by ceramide biosynthesis in hepatocytes. Our work showcases a generic therapeutic framework for targeting components of the ceramide enzymatic machinery to disentangle their roles in disease causality and to explore their utility for treatment of cardiometabolic disorders.


Assuntos
Doenças Cardiovasculares , Oligonucleotídeos Antissenso , Oxirredutases , Biomarcadores , Doenças Cardiovasculares/genética , Ceramidas , Inativação Gênica , Hepatócitos , Humanos , Oligonucleotídeos Antissenso/genética , Oxirredutases/antagonistas & inibidores , Plasma
19.
Anim Welf ; 32: e2, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38487454

RESUMO

Population control of the house mouse (Mus musculus), Norway rat (Rattus norvegicus) and black rat (Rattus rattus) is common practice worldwide. Our objective was to assess the impact on animal welfare of lethal and non-lethal control methods, including three dispatch methods. We used the Sharp and Saunders welfare assessment model with eight experts scoring eleven control methods and three dispatch methods used on the three species. We presumed the methods were performed as prescribed, only taking into account the effect on the target animal (and not, for example, on non-target catches). We did not assess population control efficacy of the methods. Methods considered to induce the least suffering to the target animal were captive-bolt traps, electrocution traps and cervical dislocation, while those with the greatest impact were anticoagulants, cholecalciferol and deprivation. Experts indicated considerable uncertainty regarding their evaluation of certain methods, which emphasises the need for further scientific research. In particular, the impact of hydrogen cyanide, chloralose and aluminium phosphide on animal welfare ought to be investigated. The experts also stressed the need to improve Standard Operating Procedures and to incorporate animal welfare assessments in Integrated Pest Management (IPM). The results of our study can help laypeople, professionals, regulatory agencies and legislators making well-informed decisions as to which methods to use when controlling commensal rodents.

20.
Int J Mol Sci ; 24(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175728

RESUMO

In this study, we considered some pesticides as active substances within formulations for the protection of plant-based food in the Republic of Serbia in silico, because these pesticides have not often been investigated in this way previously, and in an analytical way, because there are not very many available fast, cheap, and easy methods for their determination in real agricultural samples. Seven pesticides were detected in selected agricultural products (tomatoes, cucumbers, peppers, and grapes) using the QuEChERS methodology and HPLC-DAD. Standard curves for the investigated pesticides (chlorantraniliprole, methomyl, metalaxyl, thiacloprid, acetamiprid, emamectin benzoate, and cymoxanil) show good linearity, with R2 values from 0.9785 to 0.9996. The HPLC-DAD method is fast, and these pesticides can be determined in real spiked samples in less than 15 min. We further characterized the pesticides we found in food based on physicochemical properties and molecular descriptors to predict the absorption, distribution, metabolism, elimination, and toxicity (ADMET) of the compounds. We summarized the data supporting their effects on humans using various computational tools to determine their potential adverse effects. The results of our prediction study show that all of the selected pesticides considered in this study have good oral bioavailability, and those with high toxicity, therefore, could be harmful to human health. Chlorantraniliprole was shown in a molecular docking study as a good starting point for a new Alzheimer's disease drug candidate.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/química , Cromatografia Líquida de Alta Pressão/métodos , Simulação de Acoplamento Molecular , ortoaminobenzoatos , Resíduos de Praguicidas/análise
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