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1.
Nature ; 579(7798): 245-249, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32161388

RESUMEN

Skeletal inclusions in approximately 99-million-year-old amber from northern Myanmar provide unprecedented insights into the soft tissue and skeletal anatomy of minute fauna, which are not typically preserved in other depositional environments1-3. Among a diversity of vertebrates, seven specimens that preserve the skeletal remains of enantiornithine birds have previously been described1,4-8, all of which (including at least one seemingly mature specimen) are smaller than specimens recovered from lithic materials. Here we describe an exceptionally well-preserved and diminutive bird-like skull that documents a new species, which we name Oculudentavis khaungraae gen. et sp. nov. The find appears to represent the smallest known dinosaur of the Mesozoic era, rivalling the bee hummingbird (Mellisuga helenae)-the smallest living bird-in size. The O. khaungraae specimen preserves features that hint at miniaturization constraints, including a unique pattern of cranial fusion and an autapomorphic ocular morphology9 that resembles the eyes of lizards. The conically arranged scleral ossicles define a small pupil, indicative of diurnal activity. Miniaturization most commonly arises in isolated environments, and the diminutive size of Oculudentavis is therefore consistent with previous suggestions that this amber formed on an island within the Trans-Tethyan arc10. The size and morphology of this species suggest a previously unknown bauplan, and a previously undetected ecology. This discovery highlights the potential of amber deposits to reveal the lowest limits of vertebrate body size.


Asunto(s)
Dinosaurios/anatomía & histología , Dinosaurios/clasificación , Fósiles , Ámbar , Animales , Tamaño Corporal , Mianmar , Especificidad de la Especie
2.
Science ; 367(6482)2020 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-32139519

RESUMEN

The brain, with its diverse physiology and intricate cellular organization, is the most complex organ of the mammalian body. To expand our basic understanding of the neurobiology of the brain and its diseases, we performed a comprehensive molecular dissection of 10 major brain regions and multiple subregions using a variety of transcriptomics methods and antibody-based mapping. This analysis was carried out in the human, pig, and mouse brain to allow the identification of regional expression profiles, as well as to study similarities and differences in expression levels between the three species. The resulting data have been made available in an open-access Brain Atlas resource, part of the Human Protein Atlas, to allow exploration and comparison of the expression of individual protein-coding genes in various parts of the mammalian brain.


Asunto(s)
Atlas como Asunto , Encéfalo/fisiología , Regulación de la Expresión Génica , Proteínas del Tejido Nervioso/genética , Transcriptoma , Animales , Conjuntos de Datos como Asunto , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Especificidad de Órganos/genética , Especificidad de la Especie , Porcinos
3.
Rev Med Suisse ; 16(686): 522-524, 2020 Mar 18.
Artículo en Francés | MEDLINE | ID: mdl-32186796

RESUMEN

Sex needs recognition and synchronization. Many levels are found, from chemical cell recognition to mirror neurons which anticipate actions and emotions of a partner. Some animals recognize species, but not sex. Many more recognize sex, but not individuals. Individualized sex and/or social relations are only found in birds and mammals. Imprinting defines sex objects and goals, stereotyped or flexible, according to species. In humans, sex imprinting conditions sex orientation, practices and response to contradictory prescriptions of personal drives, social rules, fashion, medias and life history's contingencies.


Asunto(s)
Aves/fisiología , Mamíferos/fisiología , Preferencia en el Apareamiento Animal , Animales , Emociones , Humanos , Neuronas Espejo/fisiología , Caracteres Sexuales , Especificidad de la Especie
4.
Arch Virol ; 165(3): 557-570, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32036428

RESUMEN

Codon usage bias (CUB) arises from the preference for a codon over codons for the same amino acid. The major factors contributing to CUB are evolutionary forces, compositional properties, gene expression, and protein properties. The present analysis was performed to investigate the compositional properties and the extent of CUB across the genomes of members of the family Hepadnaviridae, as previously no work using bioinformatic tools has been reported. The viral genes were found to be AT rich with low CUB. Analysis of relative synonymous codon usage (RSCU) was used to identify overrepresented and underrepresented codons for each amino acid. Correlation analysis of overall nucleotide composition and its composition at the third codon position suggested that mutation pressure might influence the CUB. A highly significant correlation was observed between GC12 and GC3 (r = 0.910, p < 0.01), indicating that directional mutation affected all three codon positions across the genome. Translational selection (P2) and mutational responsive index (MRI) values of genes suggested that mutation plays a more important role than translational selection in members of the family Hepadnaviridae.


Asunto(s)
Regulación Viral de la Expresión Génica/fisiología , Genoma Viral/fisiología , Hepadnaviridae/metabolismo , Proteínas Virales/metabolismo , Evolución Biológica , Hepadnaviridae/genética , Mutación , ARN Mensajero , ARN Viral , Especificidad de la Especie , Proteínas Virales/genética
5.
Mikrobiyol Bul ; 54(1): 11-25, 2020 Jan.
Artículo en Turco | MEDLINE | ID: mdl-32050875

RESUMEN

The aim of this study was to investigate the frequency of Campylobacter species, to detect the antibiotic resistance profiles and the virulence genes and to determine the clonal proximity of the isolates in the samples of cutting board, slaughterhouse waste water, wall, knife and carcass from three different slaughterhouses in Kayseri region. For this purpose, a total of 150 samples, 10 of each from knife, wall, cutting board, carcass smear sample and slaughterhouse wastewater were collected from each of the three types of slaughterhouses in 2018 in Kayseri. For the isolation of the Campylobacter species, following preenrichment, the suspensions were inoculated onto modified charcoal cefoperazone desoxycholate (CCD) agar and were incubated at 37°C under microaerophilic condition for 48-72 hours. Suspicious colonies with gray-white color were recovered and subjected to phenotypical (Gram staining, oxidase, catalase test, and motion test) tests. Multiplex polymerase chain reaction (mPCR) was used for the molecular identification of the Campylobacter species. Antimicrobial susceptibilities of the isolates identified at the species level were detected by using the disk diffusion test and antibiotic gradient test. Virulence genes (iam, cadF, cdtA, flaA, ceuE, cdtC, cdtB and virB11) among the isolates were evaluated by PCR. The molecular typing of the isolates determined at species level was performed by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR). In the study, 17 (11.3%) of the 150 samples taken from the slaughterhouse were found to be suspicious in terms of Campylobacter spp. and as a result of phenotypic identification tests, all of the isolates were verified as Campylobacter spp.. As a result of mPCR; eight of the isolates were identified as Campylobacter jejuni, eight as Campylobacter fetus and one as Campylobacter coli. The isolation of the Campylobacter species from different sources was found to be higher in slaughterhouse wastewater than those of others (p<0.001) and the difference in the proportional distribution of the Campylobacter species obtained from various sources was statistically significant (p<0.05). As a result of the disk diffusion test, while, all C.jejuni isolates were resistant to ciprofloxacin, 87.5%, 25%, 25% and 12.5% of C.jejuni isolates were resistant to enrofloxacin, neomycin, amoxicillin/clavulanic acid, and erythromycin, respectively. In addition, 25%, 25% and 12.5% of C.fetus isolates were resistant to amoxicillin/clavulanic acid, neomycin and gentamicin, respectively. C.coli isolate was not resistant to any of the antibiotics tested. Antibiotic gradient test results were found to be compatible with the disc diffusion test results. One of the virulence genes examined, virB11, was not detected in any of the isolates. Moreover, iam gene was not present in C.fetus and C.coli isolates, but only in one C.jejuni isolate. The flaA gene was detected in six C.jejuni isolates. C.coli isolate and seven C.jejuni and seven C.fetus isolates were positive in terms of the cdtC gene. The cdtA, cdtB, ceuE and cadF genes were found to be positive in all C.jejuni isolates. All isolates analyzed in the study demonstrated different ERIC-PCR profiles. In conclusion, it was shown that Campylobacter strains isolated from slaughterhouses were resistant to the most of the current antibiotics. Moreover, the presence of highly virulent Campylobacters in the slaughterhouse environment threatens public health due to the risk of contamination of the humans via carcasses and foods. Therefore, it is recommended that strict hygiene rules should be followed to reduce Campylobacter species contamination in slaughterhouses.


Asunto(s)
Campylobacter , Virulencia , Mataderos , Antibacterianos/farmacología , Campylobacter/efectos de los fármacos , Campylobacter/genética , Campylobacter/patogenicidad , Humanos , Especificidad de la Especie , Virulencia/genética
6.
Zoolog Sci ; 37(1): 79-90, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32068377

RESUMEN

We describe here a new pterobranch, Cephalodiscus planitectus sp. nov. This pterobranch was collected from rocky slopes, at 100-300 m depth, off Jogashima Island, Sagami Bay, Japan. The tubaria of this new species have unique morphological features that differentiate it from known species. The tubaria are usually isolated from one another and have a completely flat and smooth surface that is devoid of erect features and projecting spines. Each has a simple, non-branched tubular cavity that is usually inhabited by a mature animal and its asexually budding offspring. The zooids have three pairs of tentaculated arms. A single bud is produced on the dorsal side of the stalk in adult zooids. In one instance, a live embryo was observed rotating at the bottom of a tubarium. Molecular phylogenetic analysis showed that C. planitectus is a sister group to all other Cephalodiscus species analyzed to date.


Asunto(s)
Invertebrados/anatomía & histología , Invertebrados/clasificación , Animales , Invertebrados/genética , Invertebrados/ultraestructura , Japón , Microscopía Electrónica de Rastreo , Filogenia , ARN Ribosómico 18S/genética , Especificidad de la Especie
7.
Zoolog Sci ; 37(1): 91-101, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32068378

RESUMEN

Two lineages of stream toads in the genus Ansonia from Malaysian Borneo have long been suspected to be specifically distinct on the basis of molecular data. We assessed the taxonomic status of these lineages using morphological and additional genetic data. In mtDNA phylogeny, each lineage-one from Bario, Kelabit Highlands of Sarawak, the other from Mt. Mulu of Sarawak and the Crocker Range of Sabah-is separated from other congeners by large genetic distances, comparable with those observed between heterospecific species in the genus. These lineages are also morphologically distinguishable from other species, and are considered to represent valid, independently evolving species. We therefore describe them as A. kelabitensis sp. nov. and A. kanak sp. nov.


Asunto(s)
Bufonidae/anatomía & histología , Bufonidae/clasificación , Animales , Borneo , Bufonidae/genética , Bufonidae/crecimiento & desarrollo , ADN Mitocondrial/genética , Femenino , Larva/anatomía & histología , Masculino , Filogenia , Especificidad de la Especie
8.
Syst Appl Microbiol ; 43(1): 126051, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31892483

RESUMEN

A polyphasic study was undertaken to establish the taxonomic status of three Modestobacter strains isolated from a high altitude Atacama Desert soil. The isolates, strains 1G6T, 1G14 and 1G50, showed chemotaxonomic and morphological properties characteristic of members of the genus Modestobacter. The peptidoglycan contained meso-diaminopimelic acid, the whole cell sugars were glucose and ribose (diagnostic sugars) and arabinose, the predominant menaquinone was MK-9(H4), polar lipid patterns contained diphosphatidylglycerol, glycophosphatidylinositol, phosphatidylethanolamine (diagnostic component), phosphatidylglycerol and phosphatidylinositol while whole cellular fatty acid profiles consisted of complex mixtures of saturated, unsaturated iso- and anteiso-components. The isolates were shown to have different BOX-PCR fingerprint and physiological profiles. They formed a distinct phyletic line in Modestobacter 16S rRNA gene trees, were most closely related to the type strain of Modestobacter italicus (99.9 % similarity) but were distinguished from this and other closely related Modestobacter type strains using a combination of phenotypic properties. Average nucleotide identity and digital DNA:DNA hybridization similarities between the draft genome sequences of isolate 1G6T and M. italicus BC 501T were 90.9 % and 42.3 %, respectively, indicating that they belong to different species. Based on these phenotypic and genotypic data it is proposed that the isolates be assigned to a novel species in the genus Modestobacter, namely as Modestobacter excelsi with isolate 1G6T (=DSM 107535T =PCM 3004T) as the type strain. Analysis of the whole genome sequence of M. excelsi 1G6T (genome size of 5.26 Mb) showed the presence of genes and gene clusters that encode for properties that are in tune with its adaptation to extreme environmental conditions that prevail in the Atacama Desert biome.


Asunto(s)
Actinobacteria/clasificación , Actinobacteria/fisiología , Clima Desértico , Microbiología del Suelo , Actinobacteria/química , Actinobacteria/citología , Altitud , ADN Bacteriano/genética , Ácidos Grasos/análisis , Genoma Bacteriano/genética , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie , Estrés Fisiológico/genética , Vitamina K 2/química
9.
Vet Parasitol ; 277: 109020, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31896019

RESUMEN

Haemonchus contortus is one of the most important gastrointestinal nematodes (GINs) infecting sheep, goats, and cattle worldwide. We developed a SYBR Green real-time PCR (qPCR) assay for detection and quantification of H. contortus by using specific primers based on a conserved region of the mitochondrial cytochrome oxidase subunit I (mt-COI) gene, and evaluated this technique in the detection of H. contortus infections in cattle in Central Anatolia Region of Turkey. The newly developed qPCR assay successfully discriminated H. contortus from other GIN species infecting cattle in the specificity evaluations, with a specific melt peak of 77.5 °C. Our results revealed the efficient amplification of the proposed target COI region within the range of plasmid copies, from 2 × 106 to 2 × 101 per µl, with 96.9 % efficiency, R² value of 0.999, and a slope of -3.398. Among the 920 cattle fecal samples from the field, 58 samples (6.3 %) were positive with qPCR assay, whereas 45 samples (4.9 %) were positive, as determined by larval culture, suggesting the utility of SYBR Green qPCR. Phylogenetic characterization of the partial COI gene of H. contortus isolates was also evaluated for 100 eggs and third stage larvae recovered from positive cattle faecal samples, which were verified with the qPCR assay prior to analyses. COI sequences were classified into three haplotypes (THC1 to THC3) with intraspecific nucleotide differences of 0.50 to 0.76 %. Phylogenetic analyses revealed that the haplotypes grouped with H. contortus isolates from several countries in a monophyletic cluster, with evidence of at least two main haplogroups. Overall, the SYBR Green qPCR assay was highly specific and sensitive, suggesting that it can be used for screening of H. contortus infections in livestock populations in epidemiological studies and the control of this important parasite.


Asunto(s)
Crianza de Animales Domésticos/métodos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/parasitología , Complejo IV de Transporte de Electrones/genética , Hemoncosis/veterinaria , Haemonchus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Animales , Bovinos , Hemoncosis/diagnóstico , Hemoncosis/parasitología , Compuestos Orgánicos/análisis , Especificidad de la Especie , Turquia
10.
Vet Parasitol ; 277: 109017, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31901535

RESUMEN

Cystic echinococcosis represents a significant problem in human and animal health and constitutes one of the most severe Neglected Tropical Diseases prioritized by the World Health Organization. The etiological agent is the complex Echinococcus granulosus sensu lato (s. l.), composed of several species/genotypes. Diagnosis in the definitive host and molecular epidemiology studies are important points for cystic echinococcosis control. Here we developed a new copro-LAMP assay, LAMP EGSL, for diagnosis in the definitive host for simultaneous detection of Echinococcus granulosus sensu stricto (s. s.), Echinococcus ortleppi, and Echinococcus canadensis species. Also, the analytical sensitivity, specificity and plausibility of performance in a rural context of a previously reported species-specific LAMP reaction, was evaluated. Both reactions showed high analytical sensitivity values (10 fg-100 fg DNA) and did not show cross reaction with DNA from host or other helminthic parasites. LAMP EGSL was performed with samples from an endemic area. In addition, the alkaline hydrolysis of one E. granulosus s. s. adult parasite followed by specific LAMP to E. granulosus s. s. was performed in a laboratory with low resources from another cystic echinococcosis endemic area. The results obtained suggest that LAMP EGSL represents a potential tool for canine diagnosis that could be useful for cystic echinococcosis control programs. In addition, we showed that LAMP reaction for E. granulous s. s., E. ortleppi and E. canadensis specific detection, could be useful for molecular epidemiology studies applicable to the definitive host. Both reactions were performed in endemic, rural areas without sophisticated equipment.


Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Enfermedades de los Perros/diagnóstico , Equinococosis/veterinaria , Echinococcus granulosus , Parasitología/métodos , Animales , Enfermedades de los Perros/parasitología , Perros , Equinococosis/diagnóstico , Equinococosis/parasitología , Sensibilidad y Especificidad , Especificidad de la Especie
11.
J Insect Sci ; 20(1)2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31925424

RESUMEN

Urbanization has a significant impact on abiotic and biotic factors in nature. We examined the morphometric characters of four carabid species (Abax parallelepipedus, Carabus scheidleri, Carabus violaceus, and Pterostichus oblongopunctatus) along urbanization gradients in and around the cities of Vienna (Austria) and Debrecen (Hungary). We found significant differences among urban, suburban, and rural areas in the parameters of antennomers, the maxillary palpus, the labial palpus, and the length of the tibia and the elytra of the carabids studied. We also found significant differences between males and females based on the parameters of antennomers, the maxillary palpus, the labial palpus, the femur, and the elytra. An interaction between urbanization and sex was found in the case of antennomers, the maxillary palpus, the labial palpus, the femur, and the elytra. Our findings suggested that in the cases of species from Carabini tribus the parameters of antennomers, the maxillary palpus, and the elytra could be useful for assessing the effects of urbanization because these morphometric characters responded sensitively to the environmental stress, whereas the most useful parameters are those of antennomers and the tibia for the species of Pterostichini tribus. Our findings also revealed that females are more sensitive to environmental stress than males.


Asunto(s)
Escarabajos/anatomía & histología , Urbanización , Animales , Austria , Ciudades , Femenino , Hungría , Masculino , Especificidad de la Especie
12.
J Zoo Wildl Med ; 50(4): 853-860, 2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31926515

RESUMEN

Parenteral nutrition (PN) is one method of providing nutrient support to hospitalized, nondomestic ruminants that have a decreased appetite in hospital or have high metabolic demands caused by illness. There are a limited number of published reports of the use of PN in nondomestic ruminants. A retrospective evaluation of PN use in adult (>6 mo of age) hospitalized ruminants at the San Diego Zoo Safari Park was conducted from 2014 to 2018 (n = 24). Discharge rate for animals that received PN was 34%. Poor survival was likely caused by case selection of animals that had severe disease or malnutrition necessitating the need for PN. Common metabolic changes among the study animals included the following: hypokalemia, hyperglycemia, and hyperphosphatemia or hypophosphatemia. Bivariable analysis revealed no clinically significant factors that influenced odds of survival. There was little evidence of adverse effects with the administration of PN during the study period. Parenteral nutrition requires specialized equipment and technical skills, but is a viable means of nutrient support for hospitalized nondomestic ruminants.


Asunto(s)
Nutrición Parenteral/veterinaria , Rumiantes , Enfermedades de los Animales/mortalidad , Enfermedades de los Animales/terapia , Animales , Animales de Zoológico , Femenino , Masculino , Estudios Retrospectivos , Factores de Riesgo , Especificidad de la Especie
13.
J Zoo Wildl Med ; 50(4): 879-890, 2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31926519

RESUMEN

Between July 2007 and June 2017 there were 86 deaths in the populations of eight caecilian species at the Zoological Society of London (ZSL) London Zoo. The mortality rate (deaths per animal-year at risk) ranged from 0.03 in the Congo caecilian (Herpele squalostoma) to 0.85 in Kaup's caecilian (Potomotyphlus kaupii). Among the 73 individuals examined post mortem, no cause of death or primary diagnosis could be established in 35 cases, but of the others the most common cause of death was dermatitis (22 cases). When all significant pathological findings were considered, skin lesions of varying types were again the commonest (56 cases), particularly among the aquatic species: Typhlonectes compressicauda (18 out of 21 cases), T. natans (8/10) and P. kaupii (12/14). Other common findings were poor gut-fill (35 cases), kidney and gastrointestinal lesions (10 cases each), generalized congestion (8 cases) and poor body condition (6 cases). This review adds to the growing body of knowledge regarding the presentations and causes of disease in captive caecilians.


Asunto(s)
Anfibios/clasificación , Animales de Zoológico , Animales , Estaciones del Año , Especificidad de la Especie
15.
Syst Appl Microbiol ; 43(2): 126052, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31932140

RESUMEN

Acute oak decline (AOD) affects native UK oak species causing rapid decline and mortality in as little as five years. A major symptom of AOD is black weeping stem lesions associated with bacterial phytopathogens, Brenneria goodwinii and Gibbsiella quercinecans. However, there is limited knowledge on the ecological and environmental reservoirs of these phytopathogens. Rainwater and soils are common reservoirs of plant pathogens in a forest environment; therefore, the aim of this study was to investigate the survival of B. goodwinii and G. quercinecans in vitro when inoculated into rainwater and forest soil using a combination of agar-based colony counts and gyrB gene-targeted quantitative PCR (qPCR). Brenneria goodwinii lost viability on inoculation into soil and rainwater, but was detectable at low abundance in soil for 28 days using qPCR, suggesting a limited ability to persist outside of the host, potentially in a viable but non-culturable (VBNC) state. Conversely, Gibbsiella quercinecans, was re-isolated from rainwater for the entire duration of the experiment (84 days) and was re-isolated from forest soil after 28 days, with qPCR analysis corroborating these trends. These data demonstrate that B. goodwinii is unable to survive in forest soils and rainwater, suggesting that it may be an endosymbiont of oak trees, whereas G. quercinecans remains viable in soil and rainwater biomes, suggesting a broad ecological distribution. These data advance understanding of the potential epidemiology of AOD-associated bacteria and their ecological reservoirs, thus increasing the overall knowledge of the pathology of AOD, which assists the development of future management strategies.


Asunto(s)
Enterobacteriaceae/fisiología , Bosques , Gammaproteobacteria/fisiología , Enfermedades de las Plantas/microbiología , Quercus/microbiología , Lluvia/microbiología , Microbiología del Suelo , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Gammaproteobacteria/crecimiento & desarrollo , Gammaproteobacteria/aislamiento & purificación , Viabilidad Microbiana , Especificidad de la Especie
16.
Nat Commun ; 11(1): 6, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31900419

RESUMEN

Uncovering whether convergent adaptations share a genetic basis is consequential for understanding the evolution of phenotypic diversity. This information can help us understand the extent to which shared ancestry or independent evolution shape adaptive phenotypes. In this study, we first ask whether the same genes underlie polymorphic mimicry in Papilio swallowtail butterflies. By comparing signatures of genetic variation between polymorphic and monomorphic species, we then investigate how ancestral variation, hybridization, and independent evolution contributed to wing pattern diversity in this group. We report that a single gene, doublesex (dsx), controls mimicry across multiple taxa, but with species-specific patterns of genetic differentiation and linkage disequilibrium. In contrast to widespread examples of phenotypic evolution driven by introgression, our analyses reveal distinct mimicry alleles. We conclude that mimicry evolution in this group was likely facilitated by ancestral polymorphism resulting from early co-option of dsx as a mimicry locus, and that evolutionary turnover of dsx alleles may underlie the wing pattern diversity of extant polymorphic and monomorphic lineages.


Asunto(s)
Mariposas Diurnas/genética , Proteínas de Unión al ADN/genética , Proteínas de Insectos/genética , Animales , Mimetismo Biológico , Mariposas Diurnas/clasificación , Mariposas Diurnas/metabolismo , Proteínas de Unión al ADN/metabolismo , Evolución Molecular , Femenino , Proteínas de Insectos/metabolismo , Masculino , Fenotipo , Filogenia , Especificidad de la Especie
17.
Appl Microbiol Biotechnol ; 104(5): 1891-1904, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31932894

RESUMEN

The genus Colletotrichum comprises species with different lifestyles but is mainly known for phytopathogenic species that infect crops of agronomic relevance causing considerable losses. The fungi of the genus Colletotrichum are distributed in species complexes and within each complex some species have particularities regarding their lifestyle. The most commonly found and described lifestyles in Colletotrichum are endophytic and hemibiotrophic phytopathogenic. Several of these phytopathogenic species show wide genetic variability, which makes long-term maintenance of resistance in plants difficult. Different mechanisms may play an important role in the emergence of genetic variants but are not yet fully understood in this genus. These mechanisms include heterokaryosis, a parasexual cycle, sexual cycle, transposable element activity, and repeat-induced point mutations. This review provides an overview of the genus Colletotrichum, the species complexes described so far and the most common lifestyles in the genus, with a special emphasis on the mechanisms that may be responsible, at least in part, for the emergence of new genotypes under field conditions.


Asunto(s)
Colletotrichum/crecimiento & desarrollo , Colletotrichum/genética , Variación Genética/genética , Enfermedades de las Plantas/microbiología , Elementos Transponibles de ADN/genética , Endófitos , Genoma Fúngico/genética , Especificidad del Huésped , Secuencias Repetitivas de Ácidos Nucleicos/genética , Especificidad de la Especie
18.
Nat Commun ; 11(1): 545, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992718

RESUMEN

Severe droughts have the potential to reduce forest productivity and trigger tree mortality. Most trees face several drought events during their life and therefore resilience to dry conditions may be crucial to long-term survival. We assessed how growth resilience to severe droughts, including its components resistance and recovery, is related to the ability to survive future droughts by using a tree-ring database of surviving and now-dead trees from 118 sites (22 species, >3,500 trees). We found that, across the variety of regions and species sampled, trees that died during water shortages were less resilient to previous non-lethal droughts, relative to coexisting surviving trees of the same species. In angiosperms, drought-related mortality risk is associated with lower resistance (low capacity to reduce impact of the initial drought), while it is related to reduced recovery (low capacity to attain pre-drought growth rates) in gymnosperms. The different resilience strategies in these two taxonomic groups open new avenues to improve our understanding and prediction of drought-induced mortality.


Asunto(s)
Sequías , Árboles/crecimiento & desarrollo , Adaptación Fisiológica , Cambio Climático , Cycadopsida/crecimiento & desarrollo , Ecología , Bosques , Magnoliopsida/crecimiento & desarrollo , Mortalidad , Suelo/química , Especificidad de la Especie , Estrés Fisiológico , Análisis de Supervivencia , Árboles/clasificación , Agua
19.
J Enzyme Inhib Med Chem ; 35(1): 398-403, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31899979

RESUMEN

(2-(2,4-Dichlorophenyl)-3-(1H-indol-1-yl)-1-(1,2,4-1H-triazol-1-yl)propan-2-ol (8 g), a new 1,2,4-triazole-indole hybrid molecule, showed a broad-spectrum activity against Candida, particularly against low fluconazole-susceptible species. Its activity was higher than fluconazole and similar to voriconazole on C. glabrata (MIC90 = 0.25, 64 and 1 µg/mL, respectively), C. krusei (MIC90 = 0.125, 64 and 0.125 µg/mL, respectively) and C. albicans (MIC90 = 0.5, 8 and 0.25 µg/mL, respectively). The action mechanisms of 8 g were also identified as inhibition of ergosterol biosynthesis and phospholipase A2-like activity. At concentration as low as 4 ng/mL, 8g inhibited ergosterol production by 82% and induced production of 14a-methyl sterols, that is comparable to the results obtained with fluconazole at higher concentration. 8 g demonstrated moderate inhibitory effect on phospholipase A2-like activity being a putative virulence factor. Due to a low MRC5 cytotoxicity, this compound presents a high therapeutic index. These results pointed out that 8 g is a new lead antifungal candidate with potent ergosterol biosynthesis inhibition.


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Indoles/farmacología , Triazoles/farmacología , Animales , Antifúngicos/química , Candida/enzimología , Candida/metabolismo , Línea Celular , Ergosterol/antagonistas & inhibidores , Ergosterol/biosíntesis , Femenino , Humanos , Indoles/química , Ratones , Pruebas de Sensibilidad Microbiana , Especificidad de la Especie , Triazoles/química
20.
Mar Environ Res ; 154: 104871, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31928985

RESUMEN

In this study, we examined the effects of increased temperature (15, 20 and 25 °C) and different light levels (50, 200 µmol photons m-2 s-1) on two widely distributed diatoms, namely Phaeodactylum tricornutum and Thalassiosira weissflogii. Results showed that increasing light level counteracted the negative effects of high temperature on photosynthesis in both species, suggesting an antagonistic interaction between light and temperature. Contrary to the above results, light limitation diminished the temperature-sensitivity of carbonic anhydrase activity in two diatoms. We also observed species-specific responses of biomass, where increased temperature significantly decreased the biomass of P. tricornutum at both low and high light levels but showed no effects on T. weissflogii. Our study demonstrated that light can alter the physiological responses of diatoms to temperature but also revealed interspecific variations. We predict that in the future ocean with shallower upper mixed layer, T. weissflogii may be more competitive than P. tricornutum.


Asunto(s)
Diatomeas , Biomasa , Luz , Fotosíntesis , Especificidad de la Especie , Temperatura Ambiental
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