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1.
PLoS Genet ; 17(4): e1009537, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33901177

RESUMO

Morphogenesis and differentiation are important stages in organ development and shape determination. However, how they are balanced and tuned during development is not fully understood. In the compound leaved tomato, an extended morphogenesis phase allows for the initiation of leaflets, resulting in the compound form. Maintaining a prolonged morphogenetic phase in early stages of compound-leaf development in tomato is dependent on delayed activity of several factors that promote differentiation, including the CIN-TCP transcription factor (TF) LA, the MYB TF CLAU and the plant hormone Gibberellin (GA), as well as on the morphogenesis-promoting activity of the plant hormone cytokinin (CK). Here, we investigated the genetic regulation of the morphogenesis-differentiation balance by studying the relationship between LA, CLAU, TKN2, CK and GA. Our genetic and molecular examination suggest that LA is expressed earlier and more broadly than CLAU and determines the developmental context of CLAU activity. Genetic interaction analysis indicates that LA and CLAU likely promote differentiation in parallel genetic pathways. These pathways converge downstream on tuning the balance between CK and GA. Comprehensive transcriptomic analyses support the genetic data and provide insights into the broader molecular basis of differentiation and morphogenesis processes in plants.


Assuntos
Diferenciação Celular/genética , Citocininas/genética , Giberelinas/metabolismo , Morfogênese/genética , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Desenvolvimento Vegetal/genética , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38878149

RESUMO

Deficits in effortful control (EC) contribute to patterns of maladaptation across development; however, little is known about how specific subfactors of EC differentially predict children's externalizing psychopathology. Using a longitudinal sample of 206 children (47.8% female, 42.6% Caucasian), the current study employed a bi-factor structural equation modeling approach to examine the concurrent and longitudinal associations between EC and its subfactors (i.e., attentional focusing, low-intensity pleasure, perceptual sensitivity, inhibitory control) and conduct problems, attention deficit disordered behaviors (ADD), and callous-unemotional (CU) traits at 36 and 84 months, respectively. Results indicated that increased general EC at 36 months predicted reduced CU traits and ADD at 84 months. Attentional focusing was the only subfactor to uniquely predict later CU traits, suggesting that strong attentional abilities attenuate risk for CU trait development. The implications for research and practice are discussed.

3.
Mol Plant Microbe Interact ; 36(8): 502-515, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37147768

RESUMO

Lasiodiplodia theobromae attacks over 500 plant species and is an important pathogen of tropical and subtropical fruit. Due to global warming and climate change, the incidence of disease associated with L. theobromae is rising. Virulence tests performed on avocado and mango branches and fruit showed a large diversity of virulence of different L. theobromae isolates. Genome sequencing was performed for two L. theobromae isolates, representing more virulent (Avo62) and less-virulent (Man7) strains, to determine the cause of their variation. Comparative genomics, including orthologous and single-nucleotide polymorphism (SNP) analyses, identified SNPs in the less-virulent strain in genes related to secreted cell wall-degrading enzymes, stress, transporters, sucrose, and proline metabolism, genes in secondary metabolic clusters, effectors, genes involved in the cell cycle, and genes belonging to transcription factors that may contribute to the virulence of L. theobromae. Moreover, carbohydrate-active enzyme analysis revealed a minor increase in gene counts of cutinases and pectinases and the absence of a few glycoside hydrolases in the less-virulent isolate. Changes in gene-copy numbers might explain the morphological differences found in the in-vitro experiments. The more virulent Avo62 grew faster on glucose, sucrose, or starch as a single carbon source. It also grew faster under stress conditions, such as osmotic stress, alkaline pH, and relatively high temperature. Furthermore, the more virulent isolate secreted more ammonia than the less-virulent one both in vitro and in vivo. These study results describe genome-based variability related to L. theobromae virulence, which might prove useful for the mitigation of postharvest stem-end rot. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Ascomicetos , Virulência/genética , Poligalacturonase/metabolismo
4.
Infancy ; 28(1): 34-55, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36468187

RESUMO

The COVID-19 pandemic may impact the development of infants' social communication patterns with their caregivers. The current study examined continuity, stability, and bidirectional associations in maternal and infant dyadic Emotional Availability (EA) before and during the COVID-19 pandemic. Participants were 110 Israeli mother-infant dyads (51% girls) that were assessed prior to (Mage = 3.5 months) and during (Mage = 12.4 months) the pandemic. At both time points, mother-infant interactions were observed during play (nonstressful context) and tasks designed to elicit infant frustration (stressful context). Maternal and child EA were coded offline. Maternal EA demonstrated no significant mean-level changes from before to during the COVID-19 pandemic, whereas infant responsiveness and involvement increased over time. Stability and bidirectional associations in EA differed by context and were evident only in the stressful context. Mothers' perceived levels of social support further moderated these associations. Specifically, infants' pre-pandemic responsiveness and involvement predicted maternal EA during the pandemic only when mothers reported low levels of social support. Our findings suggest that maternal and child EA were not adversely impacted by the COVID-19 pandemic. However, patterns of EA demonstrated moderate-to-no stability over time, suggesting considerable individual differences in trajectories of EA.


Assuntos
COVID-19 , Emoções , Relações Mãe-Filho , Feminino , Humanos , Lactente , Masculino , COVID-19/epidemiologia , Relações Mãe-Filho/psicologia , Mães/psicologia , Pandemias , Israel/epidemiologia
5.
Virol J ; 19(1): 12, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033134

RESUMO

In 1977, a sample of diseased adult honeybees (Apis mellifera) from Egypt was found to contain large amounts of a previously unknown virus, Egypt bee virus, which was subsequently shown to be serologically related to deformed wing virus (DWV). By sequencing the original isolate, we demonstrate that Egypt bee virus is in fact a fourth unique, major variant of DWV (DWV-D): more closely related to DWV-C than to either DWV-A or DWV-B. DWV-A and DWV-B are the most common DWV variants worldwide due to their close relationship and transmission by Varroa destructor. However, we could not find any trace of DWV-D in several hundred RNA sequencing libraries from a worldwide selection of honeybee, varroa and bumblebee samples. This means that DWV-D has either become extinct, been replaced by other DWV variants better adapted to varroa-mediated transmission, or persists only in a narrow geographic or host range, isolated from common bee and beekeeping trade routes.


Assuntos
Vírus de RNA , Varroidae , Animais , Abelhas , Vírus de DNA , Egito , Vírus de RNA/genética
6.
J Sleep Res ; 30(4): e13258, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33321551

RESUMO

Postpartum emotional distress is very common, with 10%-20% of postpartum women reporting depressive or anxiety disorders. Sleep is a modifiable risk factor for emotional distress that has a pivotal role in postpartum adjustment. The present study aimed to examine whether sleep duration and quality during pregnancy predict trajectories of emotional distress in the postpartum period. Participants were 215 women that were assessed from the third trimester of pregnancy to 18-months postpartum. At all five time points (third trimester, 3-, 6-, 12-, and 18-months postpartum), measures of sleep duration and quality (measured by wake time after sleep onset; WASO) were derived from both actiography and diary-based measures. Repeated measures of depression and anxiety symptoms were collected using self-report measures. Results indicated four bivariate postpartum depression and anxiety growth trajectories, including (a) high comorbidity (5.4%); (b) moderate comorbidity (19.4%); (c) low anxiety and decreasing depression symptomology (18.6%); and (d) low symptomology (56.6%). Multinomial logistic regression analyses showed that mothers with shorter sleep durations during pregnancy were more likely to belong to the high comorbidity or moderate symptoms classes compared to the low symptomology class. In addition, mothers with higher WASO (i.e. lower sleep quality) at 3-months postpartum were more likely to belong to the moderate class compared to the low symptomology class. Given the potential negative implications of disrupted sleep in the perinatal period, the present study may inform future intervention studies that target sleep problems during pregnancy.


Assuntos
Ansiedade/psicologia , Depressão Pós-Parto/psicologia , Mães/psicologia , Período Pós-Parto/psicologia , Sono , Ansiedade/complicações , Ansiedade/diagnóstico , Depressão Pós-Parto/complicações , Depressão Pós-Parto/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez
7.
BMC Genomics ; 21(1): 791, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183236

RESUMO

BACKGROUND: RNA interference (RNAi) is a highly conserved, sequence-specific gene silencing mechanism present in Eukaryotes. Three RNAi pathways are known, namely micro-RNA (miRNA), piwi-interacting RNA (piRNA) and short interfering RNA (siRNA). However, little knowledge exists about the proteins involved in these pathways in Acari. Moreover, variable successes has been obtained in gene knockdown via siRNA pathway in their functional genomics and management. We hypothesized that the clue may be in the variability of the composition and the efficacy of siRNA machinery among Acari. RESULTS: Both comparative genomic analyses and domain annotation suggest that all the analyzed species have homologs of putative core proteins that mediate cleaving of targeted genes via the three RNAi pathways. We identified putative homologs of Caenorhabditis elegans RNA-dependent RNA polymerase (RdRP) protein in all species though no secondary Argonaute homologs that operate with this protein in siRNA amplification mechanism were found, suggesting that the siRNA amplification mechanism present in Acari may be distinct from that described in C. elegans. Moreover, the genomes of these species do not encode homologs of C. elegans systemic RNAi defective-1 (Sid-1) protein that mediate silencing of the mRNA target throughout the treated organisms suggesting that the phenomena of systemic RNAi that has been reported in some Acari species probably occur through a different mechanism. However, homologs of putative RNAi spreading defective-3 (Rsd-3) protein and scavenger receptors namely Eater and SR-CI that mediate endocytosis cellular update of dsRNA in C. elegans and Drosophila melanogaster were found in Acari genomes. This result suggests that cellular dsRNA uptake in Acari is endocytosis-dependent. Detailed phylogenetic analyses of core RNAi pathway proteins in the studied species revealed that their evolution is compatible with the proposed monophyletic evolution of this group. CONCLUSIONS: Our analyses have revealed the potential activity of all three pathways in Acari. Still, much experimental work remains to be done to confirm the mechanisms behind these pathways in particular those that govern systemic/parental RNAi and siRNA amplification in Acari. Disclosure of these mechanisms will facilitate the development of new and specific management tools for the harmful species and enrichment of the beneficial species.


Assuntos
Ácaros e Carrapatos , Proteínas de Caenorhabditis elegans , Proteínas de Drosophila , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Drosophila melanogaster/metabolismo , Filogenia , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores de Superfície Celular
8.
Environ Microbiol ; 22(7): 2870-2891, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32323444

RESUMO

Colletotrichum gloeosporioides and Penicillium expansum cause postharvest diseases in tropical and deciduous fruit. During colonization, C. gloeosporioides and P. expansum secrete ammonia in hosts with low sugar content (LowSC) and gluconic acid in hosts with high sugar content (HighSC), respectively, as a mechanism to modulate enhanced pathogenicity. We studied the pathogens interactions with tomato lines of similar genetic background but differing in their sugar content. Colletotrichum gloeosporioides showed enhanced colonization of the LowSC line with differential expression response of 15% of its genes including enhanced relative expression of glycosyl hydrolases, glucanase and MFS-transporter genes. Enhanced colonization of P. expansum occurred in the HighSC line, accompanied by an increase in carbohydrate metabolic processes mainly phosphoenolpyruvate carboxykinase, and only 4% of differentially expressed genes. Gene response of the two host lines strongly differed depending on the sugar level. Limited colonization of HighSC line by C. gloeosporioides was accompanied by a marked alteration of gene expression compared the LowSC response to the same pathogen; while colonization by P. expansum resulted in a similar response of the two different hosts. We suggest that this differential pattern of fungal/host responses may be the basis for the differential of host range of both pathogens in nature.


Assuntos
Colletotrichum/genética , Interações Hospedeiro-Patógeno , Penicillium/genética , Solanum lycopersicum/microbiologia , Colletotrichum/química , Colletotrichum/patogenicidade , Frutas/microbiologia , Regulação Fúngica da Expressão Gênica , Solanum lycopersicum/química , Solanum lycopersicum/genética , Penicillium/química , Penicillium/patogenicidade , Doenças das Plantas/microbiologia , Açúcares/metabolismo , Transcriptoma , Virulência/genética
9.
J Virol ; 93(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31092571

RESUMO

Many animal and plant viruses depend on arthropods for their transmission. Virus-vector interactions are highly specific, and only one vector or one of a group of vectors from the same family is able to transmit a given virus. Poleroviruses (Luteoviridae) are phloem-restricted RNA plant viruses that are exclusively transmitted by aphids. Multiple aphid-transmitted polerovirus species commonly infect pepper, causing vein yellowing, leaf rolling, and fruit discoloration. Despite low aphid populations, a recent outbreak with such severe symptoms in many bell pepper farms in Israel led to reinvestigation of the disease and its insect vector. Here we report that this outbreak was caused by a new whitefly (Bemisia tabaci)-transmitted polerovirus, which we named Pepper whitefly-borne vein yellows virus (PeWBVYV). PeWBVYV is highly (>95%) homologous to Pepper vein yellows virus (PeVYV) from Israel and Greece on its 5' end half, while it is homologous to African eggplant yellows virus (AeYV) on its 3' half. Koch's postulates were proven by constructing a PeWBVYV infectious clone causing the pepper disease, which was in turn transmitted to test pepper plants by B. tabaci but not by aphids. PeWBVYV represents the first report of a whitefly-transmitted polerovirus.IMPORTANCE The high specificity of virus-vector interactions limits the possibility of a given virus changing vectors. Our report describes a new virus from a family of viruses strictly transmitted by aphids which is now transmitted by whiteflies (Bemisia tabaci) and not by aphids. This report presents the first description of polerovirus transmission by whiteflies. Whiteflies are highly resistant to insecticides and disperse over long distances, carrying virus inoculum. Thus, the report of such unusual polerovirus transmission by a supervector has extensive implications for the epidemiology of the virus disease, with ramifications concerning the international trade of agricultural commodities.


Assuntos
Capsicum/parasitologia , Capsicum/virologia , Hemípteros/virologia , Insetos Vetores/virologia , Luteoviridae/isolamento & purificação , Doenças das Plantas/virologia , Animais , Israel , Luteoviridae/classificação , Luteoviridae/genética , Filogenia , Homologia de Sequência
10.
New Phytol ; 225(4): 1788-1798, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31598980

RESUMO

Fruit defense against pathogens relies on induced and preformed mechanisms. The present contribution evaluated performed resistance of red and green mango fruit against the fungal pathogen Colletotrichum gloeosporioides and identified the main active antifungal components. High-performance liquid chromatography analysis of nonhydrolyzed mango peel extracts identified major anthocyanin peaks of glycosylated cyanidin and methylcyanidin, and flavonol peaks of glycosylated quercetin and kaempferol, which were more abundant on the 'red side' of red mango fruit. Organic extracts of red vs green mango peel were more efficient in inhibiting C. gloeosporioides. Transcriptome analysis of the mango-C. gloeosporioides interaction showed increased expression of glucosidase genes related to both fungal pathogenicity and host defense. Glucosidase treatment of organic peel extract increased its antifungal activity. Additionally, quercetin and cyanidin had significantly higher antifungal activity than their glycosylated derivatives. Peel extract volatiles treated with glucosidase had antifungal activity. GCMS analysis identified 15 volatiles after glucosidase hydrolysis, seven of them present only in red fruit. These results suggest that the fruit obtains a concealed arsenal of glycosylated flavonoids in its peel when they are hydrolyzed by ß-glucosidase that is induced in both fungus and host during infection process, become more toxic to the fungal pathogen, inhibiting decay development.


Assuntos
Colletotrichum/efeitos dos fármacos , Flavonoides/farmacologia , Frutas/química , Mangifera/química , Extratos Vegetais/farmacologia , Flavonoides/química , Mangifera/microbiologia , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química
11.
Arch Virol ; 165(9): 1987-1994, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32588240

RESUMO

A new virus belonging to the family Dicistroviridae was identified in the hibiscus-infesting cotton mealybug Phenacoccus solenopsis. Using high-throughput sequencing (HTS) on an Illumina HiSeq platform, a single contig of the complete genome sequence was assembled. The authenticity of the sequence obtained by HTS was validated by RT-PCR and Sanger sequencing of the amplicons, which was also employed for the 3' untranslated region (UTR). The 5' UTR was sequenced using a rapid amplification of cDNA ends kit. A large segment encompassing the whole genome was amplified by RT-PCR using viral RNA extracted from mealybugs. A whole-genome nucleotide sequence comparison showed 89% sequence identity to aphid lethal paralysis virus (ALPV), covering a short segment of 44 bp. Pairwise amino acid sequence comparisons of the protein encoded by open reading frame (ORF) 2 with its counterparts in the GenBank database, showed less than 40% identity to several members of the genus Cripavirus, including ALPV. Phylogenetic analysis based on the deduced amino acid sequence of the ORF 2 protein showed that the new virus grouped with members of the genus Cripavirus. The intergenic region (IGR) internal ribosome entry site (IRES) showed the conserved nucleotides of a type I IGR IRES and had two bulge sites, three pseudoknots, and two stem-loops. Virus morphology visualized by transmission electron microscopy demonstrated spherical particles with a diameter of ~30 nm. This virus was the only arthropod virus identified in the sampled mealybugs, and the purified virus was able to infect cotton mealybugs. To the best of our knowledge, this is the first report of a Dicistroviridae family member infecting P. solenopsis, and we have tentatively named this virus Phenacoccus solenopsis virus (PhSoV).


Assuntos
Dicistroviridae/isolamento & purificação , Hemípteros/virologia , Vírus de Insetos/isolamento & purificação , Regiões 5' não Traduzidas , Animais , Sequência de Bases , Dicistroviridae/classificação , Dicistroviridae/genética , Genoma Viral , Vírus de Insetos/classificação , Vírus de Insetos/genética , Sítios Internos de Entrada Ribossomal , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética
12.
Infancy ; 25(2): 128-150, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32749038

RESUMO

The current study examined the moderating role of infant sleep in the link between maternal factors (i.e., maternal education, depressive symptoms, sleep disturbance) and infant cognition. Data come from 95 African American parent-child dyads. At 3 months of age, infant sleep was objectively measured using videosomnography and actigraphy, from which measures of sleep regulation and consolidation were calculated. Mothers also self-reported their level of education, depressive symptoms, and sleep quality. At 6 months of age, infants completed cognitive assessments, including a measure of general cognitive ability and observed attention behavior. Findings revealed that infant sleep quality interacted with maternal education and sleep disturbances to predict cognition. Specifically, the link between maternal education and infants' attention behavior was significant and positive for infants with better regulated sleep, but not for infants with poorly regulated sleep. Similarly, the link between maternal sleep disturbance and infant cognition depended on infant sleep quality. For infants with poorer sleep consolidation, increased maternal sleep disturbance predicted poorer infant general cognitive ability. For infants with better sleep consolidation, maternal sleep disturbance was positively related to both general cognitive ability and attention behavior. These findings suggest that infant sleep quality moderates the impact of environmental factors on cognitive functioning.


Assuntos
Cognição/fisiologia , Relações Mãe-Filho , Sono/fisiologia , Actigrafia , Adulto , Depressão , Escolaridade , Feminino , Humanos , Lactente , Masculino , Mães/psicologia , Polissonografia , Psicologia da Criança
13.
Appl Environ Microbiol ; 85(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30367004

RESUMO

During nonventilated storage of carrots, CO2 gradually accumulates to high levels and causes modifications in the carrot's microbiome toward dominance of Lactobacillales and Enterobacteriales The lactic acid bacterium Leuconostoc mesenteroides secretes a slimy exudate over the surface of the carrots. The objective of this study was to characterize the slime components and the potential cause for its secretion under high CO2 levels. A proteomic analysis of the exudate revealed bacterial glucosyltransferases as the main proteins, specifically, dextransucrase. A chemical analysis of the exudate revealed high levels of dextran and several simple sugars. The exudate volume and dextran amount were significantly higher when L. mesenteroides was incubated under high CO2 levels than when incubated in an aerated environment. The treatment of carrot medium plates with commercial dextransucrase or exudate protein extract resulted in similar sugar profiles and dextran production. Transcriptome analysis demonstrated that dextran production is related to the upregulation of the L. mesenteroides dextransucrase-encoding genes dsrD and dsrT during the first 4 to 8 h of exposure to high CO2 levels compared to aerated conditions. A phylogenetic analysis of L. mesenteroides YL48 dsrD revealed a high similarity to other dsr genes harbored by different Leuconostoc species. The ecological benefit of dextran production under elevated CO2 requires further investigation. However, this study implies an overlooked role of CO2 in the physiology and fitness of L. mesenteroides in stored carrots, and perhaps in other food items, during storage under nonventilated conditions.IMPORTANCE The bacterium Leuconostoc mesenteroides is known to cause spoilage of different types of foods by secreting a slimy fluid that damages the quality and appearance of the produce. Here, we identified a potential mechanism by which high levels of CO2 affect the spoilage caused by this bacterium by upregulating dextran synthesis genes. These results have broader implications for the study of the physiology, degradation ability, and potential biotechnological applications of Leuconostoc.


Assuntos
Proteínas de Bactérias/genética , Dióxido de Carbono/metabolismo , Glucosiltransferases/genética , Leuconostoc mesenteroides/genética , Regulação para Cima , Proteínas de Bactérias/metabolismo , Daucus carota/microbiologia , Dextranos/biossíntese , Dextranos/genética , Armazenamento de Alimentos , Genes Bacterianos , Glucosiltransferases/metabolismo , Leuconostoc mesenteroides/enzimologia , Filogenia
14.
Arch Virol ; 164(6): 1691-1695, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30968213

RESUMO

Potato virus Y (PVY) is the most common virus infecting potato worldwide. We analysed potato tuber PVY infections from the major Israeli growing region in 2014-2017. Isolates were characterized by multiplex PCR according to Chikh-Ali et al. (Plant Disease 97, 1370, 2013), whose primers were not fully compatible with the Israeli isolates. New primers were designed for a multiplex PCR assay to differentiate the Israeli isolates. Three recombinant strains were observed: PVYNTNa (72% of the isolates), PVYNWi (24%) and PVYSyr-III (found only in 2015). The archetypal PVYO strain was found only once. The classical PVY strains have recently been displaced by recombinant forms, with PVYNTNa dominating. The Israeli isolates appear very similar to those of Europe (the seed tuber source), except for PVYSyr-III.


Assuntos
Reação em Cadeia da Polimerase Multiplex/métodos , Potyvirus/isolamento & purificação , Solanum tuberosum/virologia , Primers do DNA/genética , Genoma Viral , Israel , Doenças das Plantas/virologia , Potyvirus/genética , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Análise de Sequência de RNA
15.
Phytopathology ; 109(3): 488-497, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30070618

RESUMO

Recent developments in high-throughput sequencing (HTS), also called next-generation sequencing (NGS), technologies and bioinformatics have drastically changed research on viral pathogens and spurred growing interest in the field of virus diagnostics. However, the reliability of HTS-based virus detection protocols must be evaluated before adopting them for diagnostics. Many different bioinformatics algorithms aimed at detecting viruses in HTS data have been reported but little attention has been paid thus far to their sensitivity and reliability for diagnostic purposes. Therefore, we compared the ability of 21 plant virology laboratories, each employing a different bioinformatics pipeline, to detect 12 plant viruses through a double-blind large-scale performance test using 10 datasets of 21- to 24-nucleotide small RNA (sRNA) sequences from three different infected plants. The sensitivity of virus detection ranged between 35 and 100% among participants, with a marked negative effect when sequence depth decreased. The false-positive detection rate was very low and mainly related to the identification of host genome-integrated viral sequences or misinterpretation of the results. Reproducibility was high (91.6%). This work revealed the key influence of bioinformatics strategies for the sensitive detection of viruses in HTS sRNA datasets and, more specifically (i) the difficulty in detecting viral agents when they are novel or their sRNA abundance is low, (ii) the influence of key parameters at both assembly and annotation steps, (iii) the importance of completeness of reference sequence databases, and (iv) the significant level of scientific expertise needed when interpreting pipeline results. Overall, this work underlines key parameters and proposes recommendations for reliable sRNA-based detection of known and unknown viruses.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Doenças das Plantas , Biologia Computacional , Método Duplo-Cego , Reprodutibilidade dos Testes
16.
Food Microbiol ; 82: 316-324, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027789

RESUMO

Biofilm-forming Bacillus species are often involved in contamination of dairy products and therefore present a major microbiological challenge in the field of food quality and safety. In this study, we sequenced and analyzed the genomes of milk- and non-milk-derived Bacillus strains, and evaluated their biofilm-formation potential in milk. Unlike non-dairy Bacillus isolates, the dairy-associated Bacillus strains were characterized by formation of robust submerged and air-liquid interface biofilm (pellicle) during growth in milk. Moreover, genome comparison analysis revealed notable differences in putative biofilm-associated determinants between the dairy and non-dairy Bacillus isolates, which correlated with biofilm phenotype. These results suggest that biofilm formation by Bacillus species might represent a presumable adaptation strategy to the dairy environment.


Assuntos
Adaptação Fisiológica , Bacillus/fisiologia , Biofilmes/crescimento & desenvolvimento , Leite/microbiologia , Adaptação Fisiológica/genética , Animais , Bacillus/classificação , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Análise por Conglomerados , DNA Bacteriano/genética , Microbiologia de Alimentos , Genes Bacterianos/genética , Variação Genética , Genoma Bacteriano/genética , Análise de Sequência de DNA
17.
BMC Plant Biol ; 18(1): 267, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400866

RESUMO

BACKGROUND: While the role of ethylene in fruit ripening has been widely studied, the contributions of additional plant hormones are less clear. Here we examined the interactions between the transcription factor MaMADS2-box which plays a major role in banana fruit ripening and hormonal regulation. Specifically, we used MaMADS2 repressed lines in transcriptome and hormonal analyses throughout ripening and assessed hormone and gene expression perturbations as compared to wild-type (WT) control fruit. RESULTS: Our analyses revealed major differences in hormones levels and in expression of hormone synthesis and signaling genes mediated by MaMADS2 especially in preclimacteric pulp. Genes encoding ethylene biosynthesis enzymes had lower expression in the pulp of the repressed lines, consistent with reduced ethylene production. Generally, the expression of other hormone (auxin, gibberellins, abscisic acid, jasmonic acid and salicylic acid) response pathway genes were down regulated in the WT pulp prior to ripening, but remained high in MaMADS2 repressed lines. Hormone levels of abscisic acid were also higher, however, active gibberellin levels were lower and auxin levels were similar with MaMADS2 repression as compared to WT. Although abscisic level was higher in MaMADS2 repression, exogenous abscisic acid shortened the time to ethylene production and increased MaMADS2 mRNA accumulation in WT. Exogenous ethylene did not influence abscisic acid level. CRE - a cytokinin receptor, increased its expression during maturation in WT and was lower especially at prebreaker in the repressed line and zeatin level was lower at mature green of the repressed line in comparison to WT. CONCLUSIONS: In addition to previously reported effects of MaMADS2 on ethylene, this transcription factor also influences other plant hormones, particularly at the pre-climacteric stage. The cytokinin pathway may play a previously unanticipated role via MaMADS2 in banana ripening. Finally, abscisic acid enhances MaMADS2 expression to promote ripening, but the transcription factor in turn auto inhibits ABA synthesis and signaling. Together, these results demonstrate a complex interaction of plant hormones and banana fruit ripening mediated by MaMADS2.


Assuntos
Frutas/metabolismo , Musa/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Giberelinas/metabolismo , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ácido Salicílico/metabolismo
18.
J Child Psychol Psychiatry ; 59(9): 973-981, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29532459

RESUMO

BACKGROUND: Deficits of inhibitory control in early childhood are linked to externalizing behaviors and attention problems. While environmental factors and physiological processes are associated with its etiology, few studies have examined how these factors jointly predict inhibitory control. This study examined whether respiratory sinus arrhythmia (RSA) functioned as a mediator or moderator of both cumulative sociodemographic risk and parenting behaviors on inhibitory control during early childhood. METHODS: The sample included 206 children and their biological mothers. At 24, 30, and 36 months of child age dyads participated in a series of laboratory visits in which sociodemographic, parenting, and baseline RSA (RSAB) data were collected. Inhibitory control was assessed at 36 months using a gift-wrap delay task. RESULTS: A series of structural equation models yielded no evidence that RSAB mediated the relations of risk or parenting and inhibitory control. RSAB moderated the effects of risk, such that high-risk children with low RSAB performed more poorly on tasks of inhibitory control, while high-risk children with high RSAB did not. CONCLUSIONS: These results suggest that higher levels of RSAB may mitigate the influence of environmental risk on the development of inhibitory control early childhood.


Assuntos
Comportamento Infantil/fisiologia , Desenvolvimento Infantil/fisiologia , Inibição Psicológica , Comportamento Materno , Poder Familiar , Arritmia Sinusal Respiratória/fisiologia , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco
19.
Virus Genes ; 54(2): 280-289, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29429120

RESUMO

During October 2014, unfamiliar mild mosaic and mottling symptoms were identified on leaves of pepper (Capsicum chinense cv. Habanero) seedlings grown in the Arava valley in Israel 2-3 weeks post planting. Symptomatic plants were tested positive by ELISA using laboratory-produced antisera for tobamovirus species. Typical tobamovirus rod-shaped morphology was observed by transmission electron microscopy (TEM) analysis of purified virion preparation that was used for mechanical inoculation of laboratory test plants for the completion of Koch's postulates. The complete viral genome was sequenced from small interfering RNA purified from symptomatic pepper leaves and fruits by next-generation sequencing (NGS) using Illumina MiSeq platform. The contigs generated by the assembly covered 80% of the viral genome. RT-PCR amplification and Sanger sequencing were employed in order to validate the sequence generated by NGS technology. The nucleotide sequence of the complete viral genome was 99% identical to the complete genome of Paprika mild mottle virus isolate from Japan (PaMMV-J), and the deduced amino acid sequence was 99% identical to PaMMV-J protein. Amplicons from seed RNA showed 100% identity to the viral isolate from the collected symptomatic pepper plants. Partial host range analysis revealed a slow development of systemic infection in inoculated tomato plants (Lycopersicon esculentum). Interestingly, double inoculation of susceptible wild-type tomato plants and Tm-22-resistant tomato plants with the PaMMV-IL and Tomato brown rugose fruit virus (ToBRFV) resulted in accelerated viral expression in the plants.


Assuntos
Capsicum/imunologia , Capsicum/virologia , Resistência à Doença , Doenças das Plantas/virologia , Solanum lycopersicum/virologia , Tobamovirus/crescimento & desenvolvimento , Tobamovirus/isolamento & purificação , Genoma Viral , Especificidade de Hospedeiro , Israel , Japão , Microscopia Eletrônica de Transmissão , Filogenia , Folhas de Planta/virologia , Plântula/virologia , Análise de Sequência de DNA , Homologia de Sequência , Tobamovirus/genética , Tobamovirus/ultraestrutura , Vírion/ultraestrutura
20.
J Clin Child Adolesc Psychol ; 47(sup1): S435-S444, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29053384

RESUMO

The goal of this study was to examine the independent and interactive roles of harsh-intrusive maternal behaviors and children's executive function in the development of internalizing behaviors across the first years of school. A diverse sample (58% African American, 42% European American) of 137 children (48% female) was followed from kindergarten (age 5 years) through school entry (ages 6-7 years). At age 5, maternal harsh-intrusive parenting behaviors were rated from a mother-child structured play task, and children completed 3 executive function tasks that measured inhibitory control, working memory, and attention set-shifting. Teachers reported on children's internalizing behaviors at ages 5, 6, and 7. Harsh-intrusive parenting behaviors at age 5 years were positively related to internalizing behaviors in the first years of school, whereas high executive function abilities at age 5 years were related to lower internalizing behaviors in the first years of school. In addition, executive function buffered the association between parenting behaviors and internalizing behaviors such that the link between harsh-intrusive parenting and child internalizing behaviors was evident only among children with low executive function and not among children with high executive function. Interventions that focus on reducing negative parenting behaviors and improving children's executive function may prevent internalizing behaviors from increasing during times of social and academic challenge.


Assuntos
Comportamento Infantil/psicologia , Função Executiva , Comportamento Materno/psicologia , Relações Mãe-Filho/psicologia , Mães/psicologia , Estudantes/psicologia , Criança , Pré-Escolar , Função Executiva/fisiologia , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Memória de Curto Prazo/fisiologia , Poder Familiar/psicologia , Reprodutibilidade dos Testes , Instituições Acadêmicas
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