RESUMO
Colonially breeding birds and mammals form some of the largest gatherings of apex predators in the natural world and have provided model systems for studying mechanisms of population regulation in animals. According to one influential hypothesis, intense competition for food among large numbers of spatially constrained foragers should result in a zone of prey depletion surrounding such colonies, ultimately limiting their size. However, while indirect and theoretical support for this phenomenon, known as "Ashmole's halo," has steadily accumulated, direct evidence remains exceptionally scarce. Using a combination of vessel-based surveys and Global Positioning System tracking, we show that pelagic seabirds breeding at the tropical island that first inspired Ashmole's hypothesis do indeed deplete their primary prey species (flying fish; Exocoetidae spp.) over a considerable area, with reduced prey density detectable >150 km from the colony. The observed prey gradient was mirrored by an opposing trend in seabird foraging effort, could not be explained by confounding environmental variability, and can be approximated using a mechanistic consumption-dispersion model, incorporating realistic rates of seabird predation and random prey dispersal. Our results provide a rare view of the resource footprint of a pelagic seabird colony and reveal how aggregations of these central-place foraging, marine top predators profoundly influence the oceans that surround them.
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Ecossistema , Comportamento Predatório/fisiologia , Animais , Comportamento Animal , Evolução Biológica , Aves/fisiologia , Comportamento Competitivo , Comportamento Alimentar/fisiologia , Peixes/fisiologia , IlhasRESUMO
In a screen of over 200 novel pyrazole compounds, ethyl 1-(2-hydroxypentyl)-5-(3-(3-(trifluoromethyl) phenyl)ureido)-1H-pyrazole-4-carboxylate (named GeGe-3) has emerged as a potential anticancer compound. GeGe-3 displays potent anti-angiogenic properties through the presumptive targeting of the protein kinase DMPK1 and the Ca2+-binding protein calreticulin. We further explored the anticancer potential of GeGe-3 on a range of established cancer cell lines, including PC3 (prostate adenocarcinoma), SKMEL-28 (cutaneous melanoma), SKOV-3 (ovarian adenocarcinoma), Hep-G2 (hepatocellular carcinoma), MDA-MB231, SKBR3, MCF7 (breast adenocarcinoma), A549 (lung carcinoma), and HeLa (cervix epithelioid carcinoma). At concentrations in the range of 10 µM, GeGe-3 significantly restricted cell proliferation and metabolism. GeGe-3 also reduced PC3 cell migration in a standard wound closure and trans-well assay. Together, these results confirm the anticancer potential of GeGe-3 and underline the need for more detailed pre-clinical investigations into its molecular targets and mechanisms of action.
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Antineoplásicos , Movimento Celular , Proliferação de Células , Pirazóis , Humanos , Pirazóis/farmacologia , Pirazóis/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ureia/farmacologia , Ureia/química , Ureia/análogos & derivadosRESUMO
Many vertebrates show lateralized behaviour, or handedness, where an individual preferentially uses one side of the body more than the other. This is generally thought to be caused by brain lateralization and allows functional specializations such as sight, locomotion, and decision-making among other things. We deployed accelerometers on 51 northern gannets, Morus bassanus, to test for behavioural lateralization during plunge dives. When plunge diving, gannets 'roll' to one side, and standard indices indicated that 51% of individuals were left-sided, 43% right-sided, and 6% 'non-lateralized'. Lateralization indices provide no measure of error and do not account for environmental covariance, so we conducted two repeatability analyses on individuals' dive roll direction and angle. Dive side lateralization was highly repeatable among individuals over time at the population level (R = 0.878, p < 0.001). Furthermore, roll angle was also highly repeatable in individuals (R = 0.751, p < 0.001) even after controlling for lateralized state. Gannets show individual specializations in two different parts of the plunge diving process when attempting to catch prey. This is the first demonstration of lateralization during prey capture in a foraging seabird. It is also one of the few demonstrations of behavioural lateralization in a mixed model approach, providing a structure for further exploring behavioural lateralization.
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Mergulho , Lateralidade Funcional , Humanos , Animais , Especialização , Aves , LocomoçãoRESUMO
Leaf rust, caused by Puccinia hordei, is a devastating fungal disease affecting barley (Hordeum vulgare subsp. vulgare) production globally. Despite the effectiveness of genetic resistance, the deployment of single genes often compromises durability due to the emergence of virulent P. hordei races, prompting the search for new sources of resistance. Here we report on the cloning of Rph15, a resistance gene derived from barley's wild progenitor H. vulgare subsp. spontaneum. We demonstrate using introgression mapping, mutation and complementation that the Rph15 gene from the near-isogenic line (NIL) Bowman + Rph15 (referred to as BW719) encodes a coiled-coil nucleotide-binding leucine-rich repeat (NLR) protein with an integrated Zinc finger BED (ZF-BED) domain. A predicted KASP marker was developed and validated across a collection of Australian cultivars and a series of introgression lines in the Bowman background known to carry the Rph15 resistance. Rph16 from HS-680, another wild barley derived leaf rust resistance gene, was previously mapped to the same genomic region on chromosome 2H and was assumed to be allelic with Rph15 based on genetic studies. Both sequence analysis, race specificity and the identification of a knockout mutant in the HS-680 background suggest that Rph15- and Rph16-mediated resistances are in fact the same and not allelic as previously thought. The cloning of Rph15 now permits efficient gene deployment and the production of resistance gene cassettes for sustained leaf rust control.
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Basidiomycota , Hordeum , Austrália , Basidiomycota/genética , Mapeamento Cromossômico , Resistência à Doença/genética , Hordeum/genética , Doenças das Plantas/genéticaRESUMO
PURPOSE OF REVIEW: For the most part of human existence, individuals have been living a rural lifestyle in a rural setting. However, such sleep-conducive conditions have largely been transformed dramatically by urbanization within a relatively short span of time in recent history, and the resulting evolved mechanisms-environment mismatch is theorized to bring about an increased risk for insomnia symptoms. This brief review of the recent literature is designed to evaluate the veracity of this proposition. RECENT FINDINGS: The majority of recent findings have suggested that most proposed evolutionarily mismatched urban factors are indeed related to the presence of insomnia symptoms. However, there is a general paucity of longitudinal evidence (and for some other factors, a lack of enough evidence of any kind). Although there is a preponderance of recent findings indicating a link between evolutionarily mismatched urban phenomena and insomnia symptoms, more longitudinal data are needed before any causative conclusion can be drawn.
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Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Humanos , Estilo de Vida , Distúrbios do Início e da Manutenção do Sono/epidemiologia , UrbanizaçãoRESUMO
BACKGROUND: The ERG oncogene, a member of the ETS family of transcription factor encoding genes, is a genetic driver of prostate cancer. It is activated through a fusion with the androgen-responsive TMPRSS2 promoter in 50% of cases. There is therefore significant interest in developing novel therapeutic agents that target ERG. We have taken an antisense approach and designed morpholino-based oligonucleotides that target ERG by inducing skipping of its constitutive exon 4. METHODS: We designed antisense morpholino oligonucleotides (splice-switching oligonucleotides, SSOs) that target both the 5' and 3' splice sites of ERG's exon 4. We tested their efficacy in terms of inducing exon 4 skipping in two ERG-positive cell lines, VCaP prostate cancer cells and MG63 osteosarcoma cells. We measured their effect on cell proliferation, migration and apoptosis. We also tested their effect on xenograft tumour growth in mice and on ERG protein expression in a human prostate cancer radical prostatectomy sample ex vivo. RESULTS: In VCaP cells, both SSOs were effective at inducing exon 4 skipping, which resulted in a reduction of overall ERG protein levels up to 96 h following a single transfection. SSO-induced ERG reduction decreased cell proliferation, cell migration and significantly increased apoptosis. We observed a concomitant reduction in protein levels for cyclin D1, c-Myc and the Wnt signalling pathway member ß-catenin as well as a marker of activated Wnt signalling, p-LRP6. We tested the 3' splice site SSO in MG63 xenografts in mice and observed a reduction in tumour growth. We also demonstrated that the 3' splice site SSO caused a reduction in ERG expression in a patient-derived prostate tumour tissue cultured ex vivo. CONCLUSIONS: We have successfully designed and tested morpholino-based SSOs that cause a marked reduction in ERG expression, resulting in decreased cell proliferation, a reduced migratory phenotype and increased apoptosis. Our initial tests on mouse xenografts and a human prostate cancer radical prostatectomy specimen indicate that SSOs can be effective for oncogene targeting in vivo. As such, this study encourages further in vivo therapeutic studies using SSOs targeting the ERG oncogene.
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Oligonucleotídeos Antissenso/uso terapêutico , Oncogenes , Neoplasias da Próstata/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Éxons , Masculino , Camundongos , Neoplasias da Próstata/patologia , Serina Endopeptidases/genética , Regulador Transcricional ERG/análise , Regulador Transcricional ERG/antagonistas & inibidores , Regulador Transcricional ERG/genética , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Unraveling and exploiting mechanisms of disease resistance in cereal crops is currently limited by their large repeat-rich genomes and the lack of genetic recombination or cultivar (cv)-specific sequence information. We cloned the first leaf rust resistance gene Rph1 (Rph1 a) from cultivated barley (Hordeum vulgare) using "MutChromSeq," a recently developed molecular genomics tool for the rapid cloning of genes in plants. Marker-trait association in the CI 9214/Stirling doubled haploid population mapped Rph1 to the short arm of chromosome 2H in a physical region of 1.3 megabases relative to the barley cv Morex reference assembly. A sodium azide mutant population in cv Sudan was generated and 10 mutants were confirmed by progeny-testing. Flow-sorted 2H chromosomes from Sudan (wild type) and six of the mutants were sequenced and compared to identify candidate genes for the Rph1 locus. MutChromSeq identified a single gene candidate encoding a coiled-coil nucleotide binding site Leucine-rich repeat (NLR) receptor protein that was altered in three different mutants. Further Sanger sequencing confirmed all three mutations and identified an additional two independent mutations within the same candidate gene. Phylogenetic analysis determined that Rph1 clustered separately from all previously cloned NLRs from the Triticeae and displayed highest sequence similarity (89%) with a homolog of the Arabidopsis (Arabidopsis thaliana) disease resistance protein 1 protein in Triticum urartu In this study we determined the molecular basis for Rph1-mediated resistance in cultivated barley enabling varietal improvement through diagnostic marker design, gene editing, and gene stacking technologies.
Assuntos
Hordeum/fisiologia , Interações Hospedeiro-Patógeno , Proteínas NLR/fisiologia , Mapeamento Cromossômico , Genes de Plantas , Proteínas de Plantas/fisiologia , Análise de Sequência de DNARESUMO
Individual foraging specializations, where individuals use a small component of the population niche width, are widespread in nature with important ecological and evolutionary implications. In long-lived animals, foraging ability develops with age, but we know little about the ontogeny of individuality in foraging. Here we use precision global positioning system (GPS) loggers to examine how individual foraging site fidelity (IFSF), a common component of foraging specialization, varies between breeders, failed breeders and immatures in a long-lived marine predator-the northern gannet Morus bassanus Breeders (aged 5+) showed strong IFSF: they had similar routes and were faithful to distal points during successive trips. However, centrally placed immatures (aged 2-3) were far more exploratory and lacked route or foraging site fidelity. Failed breeders were intermediate: some with strong fidelity, others being more exploratory. Individual foraging specializations were previously thought to arise as a function of heritable phenotypic differences or via social transmission. Our results instead suggest a third alternative-in long-lived species foraging sites are learned during exploratory behaviours early in life, which become canalized with age and experience, and refined where possible-the exploration-refinement foraging hypothesis. We speculate similar patterns may be present in other long-lived species and moreover that long periods of immaturity may be a consequence of such memory-based individual foraging strategies.
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Fatores Etários , Comportamento Apetitivo , Aves/fisiologia , Reprodução , Animais , Ecologia , Comportamento Alimentar , Sistemas de Informação GeográficaRESUMO
BACKGROUND: Pregnant women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more likely to experience preterm birth and their neonates are more likely to be stillborn or admitted to a neonatal unit. The World Health Organization declared in May 2023 an end to the coronavirus disease 2019 (COVID-19) pandemic as a global health emergency. However, pregnant women are still becoming infected with SARS-CoV-2 and there is limited information available regarding the effect of SARS-CoV-2 infection in early pregnancy on pregnancy outcomes. OBJECTIVE AND RATIONALE: We conducted this systematic review to determine the prevalence of early pregnancy loss in women with SARS-Cov-2 infection and compare the risk to pregnant women without SARS-CoV-2 infection. SEARCH METHODS: Our systematic review is based on a prospectively registered protocol. The search of PregCov19 consortium was supplemented with an extra electronic search specifically on pregnancy loss in pregnant women infected with SARS-CoV-2 up to 10 March 2023 in PubMed, Google Scholar, and LitCovid. We included retrospective and prospective studies of pregnant women with SARS-CoV-2 infection, provided that they contained information on pregnancy losses in the first and/or second trimester. Primary outcome was miscarriage defined as a pregnancy loss before 20 weeks of gestation, however, studies that reported loss up to 22 or 24 weeks were also included. Additionally, we report on studies that defined the pregnancy loss to occur at the first and/or second trimester of pregnancy without specifying gestational age, and for second trimester miscarriage only when the study presented stillbirths and/or foetal losses separately from miscarriages. Data were stratified into first and second trimester. Secondary outcomes were ectopic pregnancy (any extra-uterine pregnancy), and termination of pregnancy. At least three researchers independently extracted the data and assessed study quality. We calculated odds ratios (OR) and risk differences (RDs) with corresponding 95% CI and pooled the data using random effects meta-analysis. To estimate risk prevalence, we performed meta-analysis on proportions. Heterogeneity was assessed by I2. OUTCOMES: We included 120 studies comprising a total of 168 444 pregnant women with SARS-CoV-2 infection; of which 18 233 women were in their first or second trimester of pregnancy. Evidence level was considered to be of low to moderate certainty, mostly owing to selection bias. We did not find evidence of an association between SARS-CoV-2 infection and miscarriage (OR 1.10, 95% CI 0.81-1.48; I2 = 0.0%; RD 0.0012, 95% CI -0.0103 to 0.0127; I2 = 0%; 9 studies, 4439 women). Miscarriage occurred in 9.9% (95% CI 6.2-14.0%; I2 = 68%; 46 studies, 1797 women) of the women with SARS CoV-2 infection in their first trimester and in 1.2% (95% CI 0.3-2.4%; I2 = 34%; 33 studies; 3159 women) in the second trimester. The proportion of ectopic pregnancies in women with SARS-CoV-2 infection was 1.4% (95% CI 0.02-4.2%; I2 = 66%; 14 studies, 950 women). Termination of pregnancy occurred in 0.6% of the women (95% CI 0.01-1.6%; I2 = 79%; 39 studies; 1166 women). WIDER IMPLICATIONS: Our study found no indication that SARS-CoV-2 infection in the first or second trimester increases the risk of miscarriages. To provide better risk estimates, well-designed studies are needed that include pregnant women with and without SARS-CoV-2 infection at conception and early pregnancy and consider the association of clinical manifestation and severity of SARS-CoV-2 infection with pregnancy loss, as well as potential confounding factors such as previous pregnancy loss. For clinical practice, pregnant women should still be advised to take precautions to avoid risk of SARS-CoV-2 exposure and receive SARS-CoV-2 vaccination.
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Aborto Espontâneo , COVID-19 , Nascimento Prematuro , Feminino , Humanos , Gravidez , Aborto Espontâneo/epidemiologia , COVID-19/epidemiologia , Nascimento Prematuro/epidemiologia , PrevalênciaRESUMO
Density-dependent competition for food influences the foraging behaviour and demography of colonial animals, but how this influence varies across a species' latitudinal range is poorly understood. Here we used satellite tracking from 21 Northern Gannet Morus bassanus colonies (39% of colonies worldwide, supporting 73% of the global population) during chick-rearing to test how foraging trip characteristics (distance and duration) covary with colony size (138-60 953 breeding pairs) and latitude across 89% of their latitudinal range (46.81-71.23° N). Tracking data for 1118 individuals showed that foraging trip duration and maximum distance both increased with square-root colony size. Foraging effort also varied between years for the same colony, consistent with a link to environmental variability. Trip duration and maximum distance also decreased with latitude, after controlling for colony size. Our results are consistent with density-dependent reduction in prey availability influencing colony size and reveal reduced competition at the poleward range margin. This provides a mechanism for rapid population growth at northern colonies and, therefore, a poleward shift in response to environmental change. Further work is required to understand when and how colonial animals deplete nearby prey, along with the positive and negative effects of social foraging behaviour.
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Plastic pollution affects many taxa worldwide, and monitoring is crucial for understanding its impacts, particularly where plastic reaches threatened species or those destined for human consumption. This study evaluates plastic ingestion in Near Threatened guanay cormorants (Leucocarbo bougainvilliorum), which catch prey that are also targeted by fisheries, through pellet analysis at ten locations in Peru. Plastic occurred in 162 (7.08 %) of 2286 pellets, consisting of mainly user plastics, including 5 % between mega or macro (>20 mm), 23 % meso (5-20 mm), 67 % micro (1-5 mm) plastics and 5 % ultrafine (1 µm-1 mm). We found significantly higher percentages occurrence of plastic for colonies close to more river mouths. Our results show that seabird pellet sampling is a useful tool for monitoring marine plastic pollution in Peru.
Assuntos
Monitoramento Ambiental , Plásticos , Animais , Humanos , Peru , Aves , Poluição Ambiental , Resíduos/análiseRESUMO
Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species.
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Plásticos , Resíduos , Animais , Plásticos/toxicidade , Resíduos/análise , Monitoramento Ambiental , Oceanos e Mares , Aves , Oceano ÍndicoRESUMO
OBJECTIVE: The purposes of this study were to 1) determine the level of professional quality of life among physical therapists and physical therapist assistants in Alabama and 2) to identify personal or professional factors that may contribute to compassion satisfaction (CS), burnout, and secondary traumatic stress (STS). METHODS: This study used a cross-sectional design and mixed-methods survey methodology to calculate odds ratios for factors affecting professional quality of life. Respondents completed a survey that included the Professional Quality of Life (ProQOL) scale, an open-ended question regarding their experience with professional burnout, and personal and professional demographics. RESULTS: Of the 742 physical therapists and physical therapist assistants in Alabama who completed the survey, the majority experienced moderate-high levels of CS and moderate-low levels of burnout and STS. Regression analyses indicated clinicians working 40 or more hours per week in patient care had greater odds for low-moderate CS and moderate-high burnout and STS subscale scores. Clinicians in our sample licensed between 6 to 15 or more than 30 years and those working in private outpatient settings had reduced odds of having moderate-high burnout, whereas those working 16 or more years had significantly increased odds for high CS scores. Responses to the open-ended question indicated workload demands and documentation as the top factors contributing to clinician burnout, while the connections with patients and coworkers help minimize such feelings. CONCLUSION: Individuals later in their career may develop protective factors to mitigate feelings of burnout compared to those early in their career. Also, clinicians working 40 or more hours per week may be more vulnerable to experiencing low-moderate CS and moderate-high burnout. Thus, individual clinicians and employers must evaluate personal, occupational, and systemic factors that contribute to reduced professional quality of life to inform preventive strategies for mitigating burnout.
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Esgotamento Profissional/psicologia , Fadiga de Compaixão/psicologia , Assistentes de Fisioterapeutas/psicologia , Fisioterapeutas/psicologia , Qualidade de Vida , Adulto , Idoso , Alabama , Estudos Transversais , Feminino , Mão de Obra em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto JovemRESUMO
Viruses are key population regulators, but we have limited knowledge of the diversity and ecology of viruses. This is even the case in wild host populations that provide ecosystem services, where small fitness effects may have major ecological impacts in aggregate. One such group of hosts are the bumblebees, which have a major role in the pollination of food crops and have suffered population declines and range contractions in recent decades. In this study, we investigate the diversity of four recently discovered bumblebee viruses (Mayfield virus 1, Mayfield virus 2, River Liunaeg virus, and Loch Morlich virus), and two previously known viruses that infect both wild bumblebees and managed honeybees (Acute bee paralysis virus and Slow bee paralysis virus) from isolates in Scotland. We investigate the ecological and environmental factors that determine viral presence and absence. We show that the recently discovered bumblebee viruses were more genetically diverse than the viruses shared with honeybees. Coinfection is potentially important in shaping prevalence: we found a strong positive association between River Liunaeg virus and Loch Morlich virus presence after controlling for host species, location and other relevant ecological variables. We tested for a relationship between environmental variables (temperature, UV radiation, wind speed, and prevalence), but as we had few sampling sites, and thus low power for site-level analyses, we could not conclude anything regarding these variables. We also describe the relationship between the bumblebee communities at our sampling sites. This study represents a first step in the description of predictors of bumblebee infection in the wild.
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Dysregulation of alternative splicing is a feature of cancer, both in aetiology and progression. It occurs because of mutations in splice sites or sites that regulate splicing, or because of the altered expression and activity of splice factors and of splice factor kinases that regulate splice factor activity. Recently the CDC2-like kinases (CLKs) have attracted attention due to their increasing involvement in cancer. We measured the effect of the CLK inhibitor, the benzothiazole TG003, on two prostate cancer cell lines. TG003 reduced cell proliferation and increased apoptosis in PC3 and DU145 cells. Conversely, the overexpression of CLK1 in PC3 cells prevented TG003 from reducing cell proliferation. TG003 slowed scratch closure and reduced cell migration and invasion in a transwell assay. TG003 decisively inhibited the growth of a PC3 cell line xenograft in nude mice. We performed a transcriptomic analysis of cells treated with TG003. We report widespread and consistent changes in alternative splicing of cancer-associated genes including CENPE, ESCO2, CKAP2, MELK, ASPH and CD164 in both HeLa and PC3 cells. Together these findings suggest that targeting CLKs will provide novel therapeutic opportunities in prostate cancer.
Assuntos
Quinases Ciclina-Dependentes/antagonistas & inibidores , Terapia de Alvo Molecular , Neoplasias da Próstata/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Processamento Alternativo/genética , Animais , Apoptose/efeitos dos fármacos , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos Nus , Invasividade Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , RNA-Seq , Tiazóis/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Fusarium graminearum (Fgr) is a devastating filamentous fungal pathogen that causes diseases in cereals, while producing mycotoxins that are toxic for humans and animals, and render grains unusable. Low efficiency in managing Fgr poses a constant need for identifying novel control mechanisms. Evidence that fungal extracellular vesicles (EVs) from pathogenic yeast have a role in human disease led us to question whether this is also true for fungal plant pathogens. We separated EVs from Fgr and performed a proteomic analysis to determine if EVs carry proteins with potential roles in pathogenesis. We revealed that protein effectors, which are crucial for fungal virulence, were detected in EV preparations and some of them did not contain predicted secretion signals. Furthermore, a transcriptomic analysis of corn (Zea mays) plants infected by Fgr revealed that the genes of some of the effectors were highly expressed in vivo, suggesting that the Fgr EVs are a mechanism for the unconventional secretion of effectors and virulence factors. Our results expand the knowledge on fungal EVs in plant pathogenesis and cross-kingdom communication, and may contribute to the discovery of new antifungals.
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Dysregulated alternative splicing plays a prominent role in all hallmarks of cancer. The splice factor kinase SRPK1 drives the activity of oncogenic splice factors such as SRSF1. SRSF1 in turn promotes the expression of splice isoforms that favour tumour growth, including proangiogenic VEGF. Knockdown (with siRNA) or chemical inhibition (using SPHINX) of SRPK1 in K562 leukemia and PC3 prostate cancer cell lines reduced cell proliferation, invasion and migration. In glomerular podocytes, the Wilms tumour suppressor zinc-finger transcription factor WT1 represses SRPK1 transcription. Here we show that in cancer cells WT1 activates SRPK1 transcription, unless a canonical WT1 binding site adjacent to the transcription start site is mutated. The ability of WT1 to activate SRPK1 transcription was reversed by the transcriptional corepressor BASP1, and both WT1 and BASP1 co-precipitated with the SRPK1 promoter. BASP1 significantly increased the expression of the antiangiogenic VEGF165b splice isoform. We propose that by upregulating SRPK1 transcription WT1 can direct an alternative splicing landscape that facilitates tumour growth.
Assuntos
Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Proteínas WT1/metabolismo , Sítios de Ligação , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Células K562 , Masculino , Células PC-3 , Regiões Promotoras Genéticas , Isoformas de Proteínas/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas WT1/antagonistas & inibidores , Proteínas WT1/genéticaRESUMO
Leptosphaeria maculans 'brassicae' is a damaging fungal pathogen of canola (Brassica napus), causing lesions on cotyledons and leaves, and cankers on the lower stem. A related species, L. biglobosa 'canadensis', colonises cotyledons but causes few stem cankers. We describe the complement of genes encoding carbohydrate-active enzymes (CAZys) and peptidases of these fungi, as well as of four related plant pathogens. We also report dual-organism RNA-seq transcriptomes of these two Leptosphaeria species and B. napus during disease. During the first seven days of infection L. biglobosa 'canadensis', a necrotroph, expressed more cell wall degrading genes than L. maculans 'brassicae', a hemi-biotroph. L. maculans 'brassicae' expressed many genes in the Carbohydrate Binding Module class of CAZy, particularly CBM50 genes, with potential roles in the evasion of basal innate immunity in the host plant. At this time, three avirulence genes were amongst the top 20 most highly upregulated L. maculans 'brassicae' genes in planta. The two fungi had a similar number of peptidase genes, and trypsin was transcribed at high levels by both fungi early in infection. L. biglobosa 'canadensis' infection activated the jasmonic acid and salicylic acid defence pathways in B. napus, consistent with defence against necrotrophs. L. maculans 'brassicae' triggered a high level of expression of isochorismate synthase 1, a reporter for salicylic acid signalling. L. biglobosa 'canadensis' infection triggered coordinated shutdown of photosynthesis genes, and a concomitant increase in transcription of cell wall remodelling genes of the host plant. Expression of particular classes of CAZy genes and the triggering of host defence and particular metabolic pathways are consistent with the necrotrophic lifestyle of L. biglobosa 'canadensis', and the hemibiotrophic life style of L. maculans 'brassicae'.