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1.
J Insect Physiol ; 131: 104244, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33891938

RESUMO

Density-dependent phase polyphenism in locusts is one of the most extreme forms of phenotypic plasticity. Locusts exist along the continuum between two density-dependent phenotypes that differ in nymphal coloration, behavior, morphology, physiology, and reproduction among others. Nymphs of the solitarious phase, found in low population densities, are usually green, relatively inactive, and avoid each other, while gregarious nymphs, found in high density, exhibit a very obvious yellow/orange background with black patterning, and are highly active and attracted to each other. The multifunctional neuropeptide [His7]-corazonin has been shown to strongly affect black coloration and several other phase-related characteristics in at least two locust species, even though no effect on phase-related behavioral traits has been found. In this study, we investigate the role of [His7]-corazonin in the Central American locust Schistocerca piceifrons (Walker), which evolved density-dependent phase polyphenism independently from the two previously studied locust species. After successfully knocking down the transcript encoding [His7]-corazonin (CRZ) using RNA interference, we show that such a knockdown influences both color and morphometrics in this species, but does not influence phase-related behavioral traits. Our results suggest that the role of [His7]-corazonin is conserved in different locust species. Finally, our study represents the first controlled study of behavioral solitarization in S. piceifrons.

2.
Zootaxa ; 4917(1): zootaxa.4917.1.1, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33756684

RESUMO

The New World Jerusalem crickets currently consist of 4 genera: Stenopelmatus Burmeister, 1838, with 33 named entities; Ammopelmatus Tinkham, 1965, with 2 described species; Viscainopelmatus Tinkham, 1970, with 1 described species, and Stenopelmatopterus Gorochov, 1988, with 3 described species. We redefine the generic boundaries of these 4 genera, synonymize Stenopelmatopterus under Stenopelmatus, and synonymize Viscainopelmatus under Ammopelmatus. We then discuss, and illustrate, all the types of the species of Stenopelmatus, all of which only occur south of the United States' border.                We recognize as valid the following 5 described Mexican and Central American species: S. ater, S. piceiventris, S. sartorianus, S. talpa, and S. typhlops. We declare the following 13 described Mexican and Central American Stenopelmatus taxa as nomen dubium: S. calcaratus, S. erythromelus, S. guatemalae, S. histrio, S. lessonae, S. lycosoides, S. mexicanus, S. minor, S. nieti, S. sallei, S. sumichrasti, S. toltecus, and S. vicinus. We designate a neotype for S. talpa and lectotypes for S. ater, S. guatemalae, S. histrio, S. lessonae, S. mexicanus, S. minor, S. nieti, S. sallei, S. sumichrasti, and S. toltecus. We assign a type locality for S. piceiventris. We concur with the previous synonymy of S. politus under S. sartorianus. We describe 14 new species of Stenopelmatus from Mexico, Honduras and Ecuador, based on a combination of adult morphology, DNA, calling song drumming pattern, distribution, and karyotype: S. chiapas sp. nov., S. cusuco sp. nov., S. diezmilpies sp. nov., S. durango sp. nov., S. ecuadorensis sp. nov., S. faulkneri sp. nov., S. honduras sp. nov., S. hondurasito sp. nov., S. mineraldelmonte sp. nov., S. nuevoleon sp. nov., S. perote sp. nov., S. saltillo sp. nov., S. sanfelipe sp. nov., and S. zimapan sp. nov.                  We transfer the following 16 described United States taxa, plus S. cephalotes from the "west coast of North America", from Stenopelmatus to Ammopelmatus: A. cahuilaensis, A. californicus, A. cephalotes, A. fasciatus, A. fuscus, A. hydrocephalus, A. intermedius, A. irregularis, A. longispinus, A. mescaleroensis, A. monahansensis, A. navajo, A. nigrocapitatus, A. oculatus, A. pictus, and A. terrenus, along with the Mexican taxon A. comanchus: these species will be discussed in a subsequent paper (Weissman et al. in prep).                We believe that all new Jerusalem cricket species descriptions should include, at a minimum, calling drum (most important) and DNA information.


Assuntos
Ortópteros/classificação , Distribuição Animal , Animais , América Central , México
3.
Artigo em Inglês | MEDLINE | ID: mdl-33445662

RESUMO

Hollow fiber membrane contactors (HFMCs) provide a large specific surface area. Thus, their significantly reduced volume provides an advantage compared to the conventional gas-liquid contactor. In this study, the selective removal efficiency of flue gas, in which sulfur oxide (SO2) and carbon dioxide (CO2) coexist, was measured using a polypropylene (PP) HFMC with such advantages. To increase the selective removal efficiency of SO2, experiments were conducted using various alkaline absorbents. As a result, with 0.05 M ammonia solution, the removal efficiency of 95% or more was exhibited with continuous operation for 100 h or more. We confirmed that the absorbent saturated by the once-through mode was aqueous ammonium sulfate ((NH4)2SO4) solution and could be used as a fertilizer without additional processing.


Assuntos
Polipropilenos , Dióxido de Enxofre , Álcalis , Dióxido de Carbono , Fenômenos Físicos
4.
F1000Res ; 9: 775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163158

RESUMO

Background: At the time of publication, the most devastating desert locust crisis in decades is affecting East Africa, the Arabian Peninsula and South-West Asia. The situation is extremely alarming in East Africa, where Kenya, Ethiopia and Somalia face an unprecedented threat to food security and livelihoods. Most of the time, however, locusts do not occur in swarms, but live as relatively harmless solitary insects. The phenotypically distinct solitarious and gregarious locust phases differ markedly in many aspects of behaviour, physiology and morphology, making them an excellent model to study how environmental factors shape behaviour and development. A better understanding of the extreme phenotypic plasticity in desert locusts will offer new, more environmentally sustainable ways of fighting devastating swarms. Methods: High molecular weight DNA derived from two adult males was used for Mate Pair and Paired End Illumina sequencing and PacBio sequencing. A reliable reference genome of Schistocerca gregaria was assembled using the ABySS pipeline, scaffolding was improved using LINKS. Results: In total, 1,316 Gb Illumina reads and 112 Gb PacBio reads were produced and assembled. The resulting draft genome consists of 8,817,834,205 bp organised in 955,015 scaffolds with an N50 of 157,705 bp, making the desert locust genome the largest insect genome sequenced and assembled to date. In total, 18,815 protein-encoding genes are predicted in the desert locust genome, of which 13,646 (72.53%) obtained at least one functional assignment based on similarity to known proteins. Conclusions: The desert locust genome data will contribute greatly to studies of phenotypic plasticity, physiology, neurobiology, molecular ecology, evolutionary genetics and comparative genomics, and will promote the desert locust's use as a model system. The data will also facilitate the development of novel, more sustainable strategies for preventing or combating swarms of these infamous insects.

6.
Nat Commun ; 11(1): 4939, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009390

RESUMO

Acoustic communication is enabled by the evolution of specialised hearing and sound producing organs. In this study, we performed a large-scale macroevolutionary study to understand how both hearing and sound production evolved and affected diversification in the insect order Orthoptera, which includes many familiar singing insects, such as crickets, katydids, and grasshoppers. Using phylogenomic data, we firmly establish phylogenetic relationships among the major lineages and divergence time estimates within Orthoptera, as well as the lineage-specific and dynamic patterns of evolution for hearing and sound producing organs. In the suborder Ensifera, we infer that forewing-based stridulation and tibial tympanal ears co-evolved, but in the suborder Caelifera, abdominal tympanal ears first evolved in a non-sexual context, and later co-opted for sexual signalling when sound producing organs evolved. However, we find little evidence that the evolution of hearing and sound producing organs increased diversification rates in those lineages with known acoustic communication.


Assuntos
Acústica , Evolução Biológica , Gafanhotos/classificação , Gafanhotos/genética , Filogenia , Vocalização Animal , Animais , Teorema de Bayes , Genoma Mitocondrial , Gafanhotos/anatomia & histologia , Audição/fisiologia , Modelos Biológicos , Som , Fatores de Tempo , Transcriptoma/genética
7.
Zootaxa ; 4838(4): zootaxa.4838.4.5, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-33056804

RESUMO

The species Melanotettix dibelonius Bruner, 1904 was previously recorded from Michoacán and Guerrero states in Mexico. This species is characterized by its tegmina, which are always shorter than head and pronotum together and sometimes shorter than the pronotum. After recent field expeditions (2015-2019) and an extensive review of museum specimens from the most important Orthoptera collections in Mexico and USA (291 specimens), we discovered a long-winged form of this species south of its previous known range, which effectively expanded its distribution range into Oaxaca state. We discuss some aspects regarding the patterns of geographic distribution and morphological variation among the long-winged and short-winged morphs. We conduct statistical analyses and observed that on average, the tegmina of long-winged individuals (both females and males) are slightly longer than twice the length of pronotum; whereas in short-winged individuals the tegmina are nearly as long or slightly longer than the length of the pronotum. Moreover, on average, females appear to have longer tegmina than males in both morphotypes. We provide photographic records of both forms live and mounted, the most comprehensive distribution map to date and a discussion of evolutionarily interesting patterns found in this species.


Assuntos
Gafanhotos , Animais , Meio Ambiente , Feminino , Masculino , México , Polimorfismo Genético
8.
PeerJ ; 8: e9618, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832268

RESUMO

Reverse Transcriptase quantitative Polymerase Chain Reaction (RT-qPCR) is the current gold standard tool for the study of gene expression. This technique is highly dependent on the validation of reference genes, which exhibit stable expression levels among experimental conditions. Often, reference genes are assumed to be stable a priori without a rigorous test of gene stability. However, such an oversight can easily lead to misinterpreting expression levels of target genes if the references genes are in fact not stable across experimental conditions. Even though most gene expression studies focus on just one species, comparative studies of gene expression among closely related species can be very informative from an evolutionary perspective. In our study, we have attempted to find stable reference genes for four closely related species of grasshoppers (Orthoptera: Acrididae) that together exhibit a spectrum of density-dependent phenotypic plasticity. Gene stability was assessed for eight reference genes in two tissues, two experimental conditions and all four species. We observed clear differences in the stability ranking of these reference genes, both between tissues and between species. Additionally, the choice of reference genes clearly influenced the results of a gene expression experiment. We offer suggestions for the use of reference genes in further studies using these four species, which should be taken as a cautionary tale for future studies involving RT-qPCR in a comparative framework.

9.
Regen Biomater ; 7(2): 213-220, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32296540

RESUMO

Titanium and its alloys are widely used in biomedical devices, e.g. implants, due to its biocompatibility and osseointegration ability. In fact, fungal (Candida spp.) infection has been identified as one of the key reasons causing the failure of the device that is inevitable and impactful to the society. Thus, this study evaluated the surface morphology, surface chemical composition and Candida albicans adhesion on specimens of 16 binary Ti-alloys (∼5 wt% of any one of the alloy elements: Ag, Al, Au, Co, Cr, Cu, Fe, In, Mn, Mo, Nb, Pd, Pt, Sn, V and Zr) compared with cp-Ti, targeting to seek for the binary Ti-alloys which has the lowest C. albicans infection. Candida albicans cultures were grown on the specimens for 48 h, and colony forming units (CFUs) and real-time polymerase chain reaction (RT-PCR) were used to evaluate the biofilm formation ability. Scanning electron microscopy and confocal laser scanning microscopy confirmed the formation of C. albicans biofilm on all specimens' surfaces, such that CFU results showed Ti-Mo, Ti-Zr, Ti-Al and Ti-V have less C. albicans formed on the surfaces than cp-Ti. RT-PCR showed Ti-Zr and Ti-Cu have significantly higher C. albicans DNA concentrations than Ti-Al and Ti-V (P < 0.05), whereas Ti-Cu has even showed a statistically higher concentration than Ti-Au, Ti-Co, Ti-In and Ti-Pt (P < 0.05). This study confirmed that Ti-Mo, Ti-Zr, Ti-Al and Ti-V have lower the occurrence of C. albicans which might be clinically advantageous for medical devices, but Ti-Cu should be used in caution.

10.
Genome Biol Evol ; 12(3): 88-102, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32211863

RESUMO

Satellite DNA (satDNA) is an abundant class of tandemly repeated noncoding sequences, showing high rate of change in sequence, abundance, and physical location. However, the mechanisms promoting these changes are still controversial. The library model was put forward to explain the conservation of some satDNAs for long periods, predicting that related species share a common collection of satDNAs, which mostly experience quantitative changes. Here, we tested the library model by analyzing three satDNAs in ten species of Schistocerca grasshoppers. This group represents a valuable material because it diversified during the last 7.9 Myr across the American continent from the African desert locust (Schistocerca gregaria), and this thus illuminates the direction of evolutionary changes. By combining bioinformatic and cytogenetic, we tested whether these three satDNA families found in S. gregaria are also present in nine American species, and whether differential gains and/or losses have occurred in the lineages. We found that the three satDNAs are present in all species but display remarkable interspecies differences in their abundance and sequences while being highly consistent with genus phylogeny. The number of chromosomal loci where satDNA is present was also consistent with phylogeny for two satDNA families but not for the other. Our results suggest eminently chance events for satDNA evolution. Several evolutionary trends clearly imply either massive amplifications or contractions, thus closely fitting the library model prediction that changes are mostly quantitative. Finally, we found that satDNA amplifications or contractions may influence the evolution of monomer consensus sequences and by chance playing a major role in driftlike dynamics.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31902005

RESUMO

Voltage-gated sodium (NaV) channels, encoded by the gene para, play a critical role in the rapid processing and propagation of visual information related to collision avoidance behaviors. We investigated their localization by immunostaining the optic lobes and central brain of the grasshopper Schistocerca americana and the vinegar fly Drosophila melanogaster with an antibody that recognizes the channel peptide domain responsible for fast inactivation gating. NaV channels were detected at high density at all stages of development. In the optic lobe, they revealed stereotypically repeating fascicles consistent with the regular structure of the eye. In the central brain, major axonal tracts were strongly labeled, particularly in the grasshopper olfactory system. We used the NaV channel sequence of Drosophila to identify an ortholog in the transcriptome of Schistocerca. The grasshopper, vinegar fly, and human NaV channels exhibit a high degree of conservation at gating and ion selectivity domains. Comparison with three species evolutionarily close to Schistocerca identified splice variants of Para and their relation to those of Drosophila. The anatomical distribution of NaV channels molecularly analogous to those of humans in grasshoppers and vinegar flies provides a substrate for rapid signal propagation and visual processing in the context of visually-guided collision avoidance.

12.
J Eukaryot Microbiol ; 67(1): 4-17, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31231936

RESUMO

Eugregarines are understudied apicomplexan parasites of invertebrates inhabiting marine, freshwater, and terrestrial environments. Most currently known terrestrial eugregarines have been described parasitizing the gut from less than 1% of total insect diversity, with a high likelihood that the remaining insect species are infected. Eugregarine diversity in orthopterans (grasshoppers, locusts, katydids, and crickets) is still little known. We carried out a survey of the eugregarines parasitizing the Mexican lubber grasshopper, Taeniopoda centurio, an endemic species to the northwest of Mexico. We described two new eugregarine species from the gut of the host: Amoebogregarina taeniopoda n. sp. and Quadruspinospora mexicana n. sp. Both species are morphologically dissimilar in their life-cycle stages. Our SSU rDNA phylogenetic analysis showed that both species are phylogenetically distant to each other, even though they parasitize the same host. Amoebogregarina taeniopoda n. sp. clustered within the clade Gregarinoidea, being closely related to Amoebogregarina nigra from the grasshopper Melanoplus differentialis. Quadruspinospora mexicana n. sp. clustered within the clade Actinocephaloidea and grouped with Prismatospora evansi, a parasite from dragonfly naiads. Amoebogregarina taeniopoda n. sp. and Q. mexicana n. sp. represent the first record of eugregarines found to infect a species of the family Romaleidae.


Assuntos
Apicomplexa/classificação , Apicomplexa/citologia , Gafanhotos/parasitologia , Interações Hospedeiro-Parasita , Filogenia , Animais , Apicomplexa/ultraestrutura , DNA de Protozoário/análise , DNA Ribossômico/análise , México , Microscopia , Microscopia Eletrônica de Varredura , Análise de Sequência de DNA
13.
Zootaxa ; 4895(3): zootaxa.4895.3.4, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33756893

RESUMO

The Indian subcontinent is known to harbor a high level of insect biodiversity and endemism, but the grasshopper fauna in this region is poorly understood, in part due to the lack of appropriate taxonomic resources. Based on detailed examinations of museum specimens and high-resolution digital images, we have produced an illustrated key to 21 Pyrgomorphidae genera known from the Indian subcontinent. This new identification key will become a useful tool for increasing our knowledge on the taxonomy of grasshoppers in this important biogeographic region.


Assuntos
Gafanhotos , Ortópteros , Animais , Museus , Filogenia
14.
Zootaxa ; 4671(1): zootaxa.4671.1.7, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31716596

RESUMO

A new king cricket species Glaphyrosoma stephanosoltis sp. nov. (Orthoptera: Anostostomatidae: Glaphyrosomatini) from mid-elevation tropical rainforests of Costa Rica is described. This new species represents the southernmost distribution of the genus Glaphyrosoma Brunner von Wattenwyl, 1888, which is widely distributed throughout Mexico, Guatemala, and Honduras. Biology of the new species is briefly described.


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Animais , Comportamento Animal , Costa Rica , Guatemala , Honduras , México
15.
J Insect Physiol ; 118: 103937, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31476314

RESUMO

Comparative quantification of reaction norms across closely related species in a clade is rare, but such a study can reveal valuable insights into understanding how reaction norms evolve along phylogeny. The grasshopper genus Schistocerca Stål (Orthoptera: Acrididae: Cyrtacanthacridinae) is an ideal group to study the evolution of density-dependent phenotypic plasticity because it includes both swarming locusts and non-swarming sedentary grasshoppers, which show varying degrees of plastic reaction norms in many traits. The swarming locusts exhibit locust phase polyphenism in which cryptically colored and solitary individuals can transform into conspicuously colored and highly gregarious individuals in response to increases in population density. The sedentary grasshoppers do not swarm in nature, and thus it has been assumed that they have little or no expression of plastic reaction norms in many traits, except for color, which has been shown to be a phylogenetically conserved trait. In this study, we have quantified density-dependent reaction norms in behavior, color, body size, and morphometric ratio in the nymphs of four sedentary species within Schistocerca by conducting explicit rearing experiments to induce potential phenotypic changes in response to isolation and crowding. In contrast to our previous assumption, we find that all four species show a certain level of density-dependent plastic reaction norms, which implies that these sedentary species have hidden reaction norms that can only be induced experimentally, some components of which must be phylogenetically conserved. Furthermore, we demonstrate that rearing density differentially affects the expression of reaction norms in different species, suggesting that different reaction norms must have followed independent evolutionary trajectories.


Assuntos
Adaptação Fisiológica , Gafanhotos/anatomia & histologia , Gafanhotos/fisiologia , Animais , Comportamento Animal , Tamanho Corporal , Cor , Ninfa/anatomia & histologia , Ninfa/fisiologia , Filogenia , Densidade Demográfica , Especificidade da Espécie
16.
Insect Biochem Mol Biol ; 113: 103208, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31422150

RESUMO

The complete mitochondrial genome of the soybean aphid (Aphis glycines Matsumura), a major agricultural pest in the world, is described for the first time, which consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, as well as a large repeat region between tRNA-Glu and tRNA-Phe, and an AT-rich control region. The 17,954 bp mtgenome is the largest reported from the family Aphididae, and its gene order follows the ancestral insect mtgenome except for the repeat region, which contains a 195 bp unit repeated 11.9 times, representing the highest reported repeats among the known aphid mtgenomes to date. A new molecular phylogeny of Aphidae is reconstructed based on all available aphid mtgenomes, and it is shown that the mtgenome data can robustly resolve relationships at the subfamily level, but do not have sufficient phylogenetic information to resolve deep relationships. A phylogeny-based comparative analysis of mtgenomes has been performed to investigate the evolution of the repeat region between tRNA-Glu and tRNA-Phe. So far, among aphids, 13 species are known to have this repeat region of variable lengths, and a phylogenetic analysis of the repeat region shows that a large proportion of the sequences are conserved across the phylogeny, suggesting that the repeat region evolved in the most recent common ancestor of Aphidinae and Eriosomatinae, and that it has gone through numerous episodes of lineage-specific losses and expansions. Combined together, this study provides novel insights into how the repeat regions have evolved within aphids.


Assuntos
Afídeos/genética , Evolução Molecular , Genoma de Inseto , Genoma Mitocondrial , Animais , Filogenia
17.
Mol Phylogenet Evol ; 139: 106537, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31212082

RESUMO

The gaudy grasshopper family Pyrgomorphidae (Orthoptera: Caelifera) shows a peculiar geographical distribution. Of the 487 described species, less than 10% of the diversity is found in the New World, while the rest occur throughout Africa, Asia, and Australia. Only 41 species belonging to four tribes are found in Central and South America and Dominican Republic, and the phylogenetic positions of these taxa within the large phylogeny of Pyrgomorphidae and the relationships among them have never been investigated. Regarding the biogeography, three different hypotheses about the origin of the New World Pyrgomorphidae have been proposed, but these have not been empirically tested. In this study, we present the first molecular phylogeny of Pyrgomorphidae that includes the members of all four New World tribes and representative genera from the Old World based on entire mitochondrial genome and four nuclear genes to investigate the biogeography of this fascinating lineage. Our results recover Pyrgomorphidae as monophyletic and the New World Pyrgomorphidae as a paraphyletic group comprising three clades, consisting of: (1) The Caribbean Jaragua + the South American Algete; (2) The Mexican and Central American Sphenarium + Prosphena; and (3) The Mexican lineages Ichthiacridini + Ichthyotettigini. The divergence time estimation analysis suggested that the Pyrgomorphidae diverged from its relatives in the Early Cretaceous (139-104 mya). The biogeographic analysis using BioGeoBEARS showed that after diversifying in the Old World, the first New World Pyrgomorphidae clade (Algete + Jaragua) diverged 96 mya (Late Cretaceous, Cenomanian) and that their current distribution in the New World is explained by two possible events, a transatlantic colonization from Africa to Northern South America or a vicariance event between these two landmasses, followed by a subsequent dispersal to the Caribbean. The second wave of colonization occurred about 69 mya towards the end of the Late Cretaceous (Maastrichtian) with dispersal from Africa to South America and then to North America with a subsequent diversification in Mexico including Baja California.


Assuntos
Gafanhotos/genética , Animais , Núcleo Celular/genética , Genoma Mitocondrial , Gafanhotos/classificação , Funções Verossimilhança , Filogenia , Filogeografia , Fatores de Tempo
18.
Philos Trans R Soc Lond B Biol Sci ; 374(1777): 20180246, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31154978

RESUMO

The repeated evolutionary specialization of distantly related insects to cardenolide-containing host plants provides a stunning example of parallel adaptation. Hundreds of herbivorous insect species have independently evolved insensitivity to cardenolides, which are potent inhibitors of the alpha-subunit of Na+,K+-ATPase (ATPα). Previous studies investigating ATPα-mediated cardenolide insensitivity in five insect orders have revealed remarkably high levels of parallelism in the evolution of this trait, including the frequent occurrence of parallel amino acid substitutions at two sites and recurrent episodes of duplication followed by neo-functionalization. Here we add data for a sixth insect order, Orthoptera, which includes an ancient group of highly aposematic cardenolide-sequestering grasshoppers in the family Pyrgomorphidae. We find that Orthopterans exhibit largely predictable patterns of evolution of insensitivity established by sampling other insect orders. Taken together the data lend further support to the proposal that negative pleiotropic constraints are a key determinant in the evolution of cardenolide insensitivity in insects. Furthermore, analysis of our expanded taxonomic survey implicates positive selection acting on site 111 of cardenolide-sequestering species with a single-copy of ATPα, and sites 115, 118 and 122 in lineages with neo-functionalized duplicate copies, all of which are sites of frequent parallel amino acid substitution. This article is part of the theme issue 'Convergent evolution in the genomics era: new insights and directions'.


Assuntos
Cardenolídeos/farmacologia , Herbivoria/efeitos dos fármacos , Herbivoria/genética , Resistência a Inseticidas , Inseticidas/farmacologia , Ortópteros/efeitos dos fármacos , Ortópteros/genética , Sequência de Aminoácidos , Animais , Evolução Biológica , Herbivoria/classificação , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Insetos/química , Insetos/classificação , Insetos/genética , Ortópteros/química , Ortópteros/classificação , Filogenia , Alinhamento de Sequência , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo
19.
Genes (Basel) ; 9(11)2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30373193

RESUMO

Supernumerary (B) chromosomes are dispensable genomic elements occurring frequently among grasshoppers. Most B chromosomes are enriched with repetitive DNAs, including satellite DNAs (satDNAs) that could be implicated in their evolution. Although studied in some species, the specific ancestry of B chromosomes is difficult to ascertain and it was determined in only a few examples. Here we used bioinformatics and cytogenetics to characterize the composition and putative ancestry of B chromosomes in three grasshopper species, Rhammatocerus brasiliensis, Schistocerca rubiginosa, and Xyleus discoideus angulatus. Using the RepeatExplorer pipeline we searched for the most abundant satDNAs in Illumina sequenced reads, and then we generated probes used in fluorescent in situ hybridization (FISH) to determine chromosomal position. We used this information to infer ancestry and the events that likely occurred at the origin of B chromosomes. We found twelve, nine, and eighteen satDNA families in the genomes of R. brasiliensis, S. rubiginosa, and X. d. angulatus, respectively. Some satDNAs revealed clustered organization on A and B chromosomes varying in number of sites and position along chromosomes. We did not find specific satDNA occurring in the B chromosome. The satDNAs shared among A and B chromosomes support the idea of putative intraspecific ancestry from small autosomes in the three species, i.e., pair S11 in R. brasiliensis, pair S9 in S. rubiginosa, and pair S10 in X. d. angulatus. The possibility of involvement of other chromosomal pairs in B chromosome origin is also hypothesized. Finally, we discussed particular aspects in composition, origin, and evolution of the B chromosome for each species.

20.
Mater Sci Eng C Mater Biol Appl ; 90: 113-118, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29853074

RESUMO

In order to increase the biocompatibility and bioactivity of chitosan, hydroxyapatite was in situ combined into the spin-coated chitosan layer on the titanium substrate by incubating in modified simulated body fluid (m-SBF). The calcium phosphate/chitosan (CaP/CS) composite prepared in m-SBF showed a homogeneous distribution of spherical nano-clusters. The hydrophilicity of the coatings was increased by performing NaOH post-treatment of CaP/CS composites, which also affected apatite formation. Biocompatibility of the coatings was assessed by investigating the cellular response of human osteoblast-like MG-63 cells with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell adhesion and osteogenic properties of the mesoporous CaP/CS composite were evaluated by SEM and ALPase assay, respectively. This in vitro study showed improved cell adhesion and differentiation on nanostructured CaP/CS composites. These results indicate that this CaP/CS composite could be a promising candidate for bone tissue engineering.


Assuntos
Fosfatos de Cálcio/química , Quitosana/química , Nanocompostos/química , Líquidos Corporais , Fosfatos de Cálcio/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanoestruturas/química
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