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1.
BMC Ecol Evol ; 21(1): 226, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34963462

RESUMO

BACKGROUND: The soft-bodied cladobranch sea slugs represent roughly half of the biodiversity of marine nudibranch molluscs on the planet. Despite their global distribution from shallow waters to the deep sea, from tropical into polar seas, and their important role in marine ecosystems and for humans (as targets for drug discovery), the evolutionary history of cladobranch sea slugs is not yet fully understood. RESULTS: To enlarge the current knowledge on the phylogenetic relationships, we generated new transcriptome data for 19 species of cladobranch sea slugs and two additional outgroup taxa (Berthella plumula and Polycera quadrilineata). We complemented our taxon sampling with previously published transcriptome data, resulting in a final data set covering 56 species from all but one accepted cladobranch superfamilies. We assembled all transcriptomes using six different assemblers, selecting those assemblies that provided the largest amount of potentially phylogenetically informative sites. Quality-driven compilation of data sets resulted in four different supermatrices: two with full coverage of genes per species (446 and 335 single-copy protein-coding genes, respectively) and two with a less stringent coverage (667 genes with 98.9% partition coverage and 1767 genes with 86% partition coverage, respectively). We used these supermatrices to infer statistically robust maximum-likelihood trees. All analyses, irrespective of the data set, indicate maximal statistical support for all major splits and phylogenetic relationships at the family level. Besides the questionable position of Noumeaella rubrofasciata, rendering the Facelinidae as polyphyletic, the only notable discordance between the inferred trees is the position of Embletonia pulchra. Extensive testing using Four-cluster Likelihood Mapping, Approximately Unbiased tests, and Quartet Scores revealed that its position is not due to any informative phylogenetic signal, but caused by confounding signal. CONCLUSIONS: Our data matrices and the inferred trees can serve as a solid foundation for future work on the taxonomy and evolutionary history of Cladobranchia. The placement of E. pulchra, however, proves challenging, even with large data sets and various optimization strategies. Moreover, quartet mapping results show that confounding signal present in the data is sufficient to explain the inferred position of E. pulchra, again leaving its phylogenetic position as an enigma.


Assuntos
Gastrópodes , Animais , Aplysia/genética , Ecossistema , Gastrópodes/genética , Humanos , Moluscos/genética , Filogenia , Transcriptoma/genética
2.
PLoS One ; 16(6): e0252221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34166422

RESUMO

The emerald jewel wasp Ampulex compressa (Hymenoptera: Ampulicidae) is a solitary wasp that is widely known for its specialized hunting of cockroaches as larvae provision. Adult wasps mainly feed on pollen and nectar, while their larvae feed on the cockroachs' body, first as ecto- and later as endoparsitoids. Little is known about the expression of digestive, detoxification and stress-response-related genes in the midgut of A. compressa, or about its transcriptional versatility between life stages. To identify gut-biased genes related to digestion, detoxification, and stress response, we explored the midgut transcriptome of lab-reared A. compressa, for both adults and larvae, by focusing on the top 100 significantly up- and down-regulated genes. From the top 100 significantly differentially expressed genes (DEGs), we identified 39 and 36 DEGs putatively related to digestion and detoxification in the adult wasps and larvae, respectively. The two carbohydrases alpha-glucosidase (containing an alpha-amylase domain) and glycosyl hydrolase family 31, as well as the two proteinases chymotrypsin and trypsin, revealed the highest gene diversity. We identified six significant DEGs related to detoxification, which comprise glutathione S-transferase, cytochrome P450s and UDP-glucuronosyltransferase. The gene expression levels that were significantly expressed in both life stages vary strongly between life stages, as found in genes encoding for chymotrypsin and trypsin or glycosyl hydrolases family 31. The number of genes related to alpha-glucosidase, glycosyl hydrolase family 31, and cytochrome P450s was found to be similar across nine reference hymenopteran species, except for the identified glycosyl hydrolase family 31 gene, which was absent in all reference bee species. Phylogenetic analyses of the latter candidate genes revealed that they cluster together with their homologous genes found in the reference hymenopteran species. These identified candidate genes provide a basis for future comparative genomic and proteomic studies on (ontogenetic) dietary transitions in Hymenoptera.


Assuntos
Baratas/fisiologia , Sistema Digestório/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Interações Hospedeiro-Parasita , Transcriptoma , Vespas/genética , Animais , Sistema Digestório/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Inativação Metabólica , Larva/fisiologia , Estresse Oxidativo , Filogenia , Vespas/fisiologia
3.
BMC Biol ; 19(1): 23, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557827

RESUMO

BACKGROUND: The most species-rich radiation of animal life in the 66 million years following the Cretaceous extinction event is that of schizophoran flies: a third of fly diversity including Drosophila fruit fly model organisms, house flies, forensic blow flies, agricultural pest flies, and many other well and poorly known true flies. Rapid diversification has hindered previous attempts to elucidate the phylogenetic relationships among major schizophoran clades. A robust phylogenetic hypothesis for the major lineages containing these 55,000 described species would be critical to understand the processes that contributed to the diversity of these flies. We use protein encoding sequence data from transcriptomes, including 3145 genes from 70 species, representing all superfamilies, to improve the resolution of this previously intractable phylogenetic challenge. RESULTS: Our results support a paraphyletic acalyptrate grade including a monophyletic Calyptratae and the monophyly of half of the acalyptrate superfamilies. The primary branching framework of Schizophora is well supported for the first time, revealing the primarily parasitic Pipunculidae and Sciomyzoidea stat. rev. as successive sister groups to the remaining Schizophora. Ephydroidea, Drosophila's superfamily, is the sister group of Calyptratae. Sphaeroceroidea has modest support as the sister to all non-sciomyzoid Schizophora. We define two novel lineages corroborated by morphological traits, the 'Modified Oviscapt Clade' containing Tephritoidea, Nerioidea, and other families, and the 'Cleft Pedicel Clade' containing Calyptratae, Ephydroidea, and other families. Support values remain low among a challenging subset of lineages, including Diopsidae. The placement of these families remained uncertain in both concatenated maximum likelihood and multispecies coalescent approaches. Rogue taxon removal was effective in increasing support values compared with strategies that maximise gene coverage or minimise missing data. CONCLUSIONS: Dividing most acalyptrate fly groups into four major lineages is supported consistently across analyses. Understanding the fundamental branching patterns of schizophoran flies provides a foundation for future comparative research on the genetics, ecology, and biocontrol.


Assuntos
Drosophila/genética , Evolução Molecular , Filogenia , Transcriptoma , Animais , Drosophila/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Larva/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Análise de Sequência de DNA
4.
Genome Biol Evol ; 12(7): 1099-1188, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32442304

RESUMO

The tremendous diversity of Hymenoptera is commonly attributed to the evolution of parasitoidism in the last common ancestor of parasitoid sawflies (Orussidae) and wasp-waisted Hymenoptera (Apocrita). However, Apocrita and Orussidae differ dramatically in their species richness, indicating that the diversification of Apocrita was promoted by additional traits. These traits have remained elusive due to a paucity of sawfly genome sequences, in particular those of parasitoid sawflies. Here, we present comparative analyses of draft genomes of the primarily phytophagous sawfly Athalia rosae and the parasitoid sawfly Orussus abietinus. Our analyses revealed that the ancestral hymenopteran genome exhibited traits that were previously considered unique to eusocial Apocrita (e.g., low transposable element content and activity) and a wider gene repertoire than previously thought (e.g., genes for CO2 detection). Moreover, we discovered that Apocrita evolved a significantly larger array of odorant receptors than sawflies, which could be relevant to the remarkable diversification of Apocrita by enabling efficient detection and reliable identification of hosts.


Assuntos
Especiação Genética , Genoma de Inseto , Interações Hospedeiro-Parasita/genética , Himenópteros/genética , Sequência de Aminoácidos , Animais , Sequência Conservada , Elementos de DNA Transponíveis , Feminino , Dosagem de Genes , Glicoproteínas/genética , Herbivoria/genética , Imunidade/genética , Proteínas de Insetos/genética , Masculino , Família Multigênica , Receptores Odorantes/genética , Comportamento Social , Visão Ocular/genética
5.
Proc Biol Sci ; 286(1895): 20182076, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30963947

RESUMO

Phylogenetic relationships among subgroups of cockroaches and termites are still matters of debate. Their divergence times and major phenotypic transitions during evolution are also not yet settled. We addressed these points by combining the first nuclear phylogenomic study of termites and cockroaches with a thorough approach to divergence time analysis, identification of endosymbionts, and reconstruction of ancestral morphological traits and behaviour. Analyses of the phylogenetic relationships within Blattodea robustly confirm previously uncertain hypotheses such as the sister-group relationship between Blaberoidea and remaining Blattodea, and Lamproblatta being the closest relative to the social and wood-feeding Cryptocercus and termites. Consequently, we propose new names for various clades in Blattodea: Cryptocercus + termites = Tutricablattae; Lamproblattidae + Tutricablattae = Kittrickea; and Blattoidea + Corydioidea = Solumblattodea. Our inferred divergence times contradict previous studies by showing that most subgroups of Blattodea evolved in the Cretaceous, reducing the gap between molecular estimates of divergence times and the fossil record. On a phenotypic level, the blattodean ground-plan is for egg packages to be laid directly in a hole while other forms of oviposition, including ovovivipary and vivipary, arose later. Finally, other changes in egg care strategy may have allowed for the adaptation of nest building and other novelties.


Assuntos
Baratas/classificação , Isópteros/classificação , Filogenia , Animais , Evolução Biológica , Baratas/genética , Isópteros/genética
6.
Am Nat ; 190(S1): S29-S43, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28731826

RESUMO

Natural selection imposed by natural toxins has led to striking levels of convergent evolution at the molecular level. Cardiac glycosides represent a group of plant toxins that block the Na,K-ATPase, a vital membrane protein in animals. Several herbivorous insects have convergently evolved resistant Na,K-ATPases, and in some species, convergent gene duplications have also arisen, likely to cope with pleiotropic costs of resistance. To understand the genetic basis and predictability of these adaptations, we studied five independent lineages of leaf-mining flies (Diptera: Agromyzidae). These flies have colonized host plants in four botanical families that convergently evolved cardiac glycosides of two structural types: cardenolides and bufadienolides. We compared each of six fly species feeding on such plants to a phylogenetically related but nonadapted species. Irrespective of the type of cardiac glycoside in the host plant, five out of six exposed species displayed substitutions in the cardiac glycoside-binding site of the Na,K-ATPase that were previously described in other insect orders; in only one species was the gene duplicated. In vitro assays of nervous tissue extractions confirmed that the substitutions lead to increased resistance of the Na,K-ATPase. Our results demonstrate that target site insensitivity of Na,K-ATPase is a common response to dietary cardiac glycosides leading to highly predictable amino acid changes; nonetheless, convergent evolution of gene duplication for this multifunctional enzyme appears more constrained.


Assuntos
Evolução Molecular , Insetos , ATPase Trocadora de Sódio-Potássio/genética , Animais , Cardenolídeos , Duplicação Gênica , Plantas/química
7.
Plast Reconstr Surg ; 125(5): 1515-1522, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20440170

RESUMO

BACKGROUND: Despite the prevalent use of hyaluronic acid-based filling materials for facial soft-tissue augmentation and favorable reports of durability in the infraorbital region, no quantitative data exist on the long-term durability of these products following injection. This study represents the first attempt to use three-dimensional imaging to quantify augmentation achieved and duration of effect with one hyaluronic acid product in the tear trough. METHODS: The authors conducted a prospective, blinded case series in a clinical setting. One non-animal stabilized hyaluronic acid material was used to augment 20 tear troughs to address cosmetic deficiency in this region. Patients were followed long term with three-dimensional imaging. Posttreatment and pretreatment images were compared, volume change was calculated at each time point, and percentage change between immediate and long-term posttreatment was evaluated. All measurements and calculations were performed independent of the injector. RESULTS: Residual effect from the hyaluronic acid product was demonstrable on three-dimensional imaging in 100 percent of tear troughs augmented in this study at the final follow-up visit. Average follow-up was 14.4 months (range, 8.5 to 22.75 months). Average initial augmentation measured by three-dimensional imaging was 0.21 cc per site. Average maintenance of effect for patients at the final follow-up visit was 85 percent. CONCLUSIONS: The long-term durability of a small gel particle-based hyaluronic acid in the tear trough is substantiated for the first time in an objective, quantitative fashion using three-dimensional imaging for evaluation of volumetric facial rejuvenation. Three-dimensional photographic imaging offers clinicians a precise and expeditious method for quantitatively evaluating volumetric changes in the face, and represents a significant advance in technology for studying the effects of facial aging.


Assuntos
Técnicas Cosméticas , Ácido Hialurônico/administração & dosagem , Órbita/anatomia & histologia , Rejuvenescimento , Materiais Biocompatíveis , Bochecha/anatomia & histologia , Seguimentos , Humanos , Imageamento Tridimensional , Injeções , Estudos Prospectivos
8.
Curr Opin Otolaryngol Head Neck Surg ; 15(4): 238-43, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17620897

RESUMO

PURPOSE OF REVIEW: The earliest techniques of facial rejuvenation have been continuously adapted to reflect changes in the understanding of the aging face. Significant, paradigm-shifting advances in this understanding have been made in recent years which have allowed application of specific therapeutic modalities, resulting in dramatically improved results over those achieved with traditional facial rejuvenation. RECENT FINDINGS: Pioneering work by several authors has shown that gravity is not the sole determinant of the aging face. These authors have demonstrated that volume loss, including that of soft tissue and bone, is at least equally important in the pathogenesis of the stigmata of aging. Rejuvenative techniques developed to reverse these atrophic changes have exhibited outstanding results. The consequence is an increasing emphasis on the use of volume restoration procedures to address the aging face. SUMMARY: Recent improvements in the understanding of the facial aging process have brought about newly refined techniques for facial rejuvenation, ushering in a new era of plastic surgery for the aging face which is being manifested by increasingly natural results.


Assuntos
Envelhecimento/fisiologia , Face/fisiologia , Face/cirurgia , Feminino , Gravitação , Humanos , Tamanho do Órgão , Rejuvenescimento
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