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1.
Pharmaceutics ; 16(5)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38794333

RESUMO

The literature data emphasize that nanoparticles might improve the beneficial effects of near-infrared light (NIR) on wound healing. This study investigates the mechanisms of the synergistic wound healing potential of NIR light and silver metal-organic frameworks combined with nitrogen- and sulfur-doped carbon dots (AgMOFsN-CDs and AgMOFsS-CDs, respectively), which was conducted by testing the fibroblasts viability, scratch assays, biochemical analysis, and synchrotron-based Fourier transform infrared (SR-FTIR) cell spectroscopy and imaging. Our findings reveal that the combined treatment of AgMOFsN-CDs and NIR light significantly increases cell viability to nearly 150% and promotes cell proliferation, with reduced interleukin-1 levels, suggesting an anti-inflammatory response. SR-FTIR spectroscopy shows this combined treatment results in unique protein alterations, including increased α-helix structures and reduced cross-ß. Additionally, protein synthesis was enhanced upon the combined treatment. The likely mechanism behind the observed changes is the charge-specific interaction of N-CDs from the AgMOFsN-CDs with proteins, enhanced by NIR light due to the nanocomposite's optical characteristics. Remarkably, the complete wound closure in the in vitro scratch assay was achieved exclusively with the combined NIR and AgMOFsN-CDs treatment, demonstrating the promising application of combined AgMOFsN-CDs with NIR light photodynamic therapy in regenerative nanomedicine and tissue engineering.

2.
PLoS Genet ; 20(2): e1011129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38346089

RESUMO

Lewontin's paradox, the observation that levels of genetic diversity (π) do not scale linearly with census population size (Nc) variation, is an evolutionary conundrum. The most extreme mismatches between π and Nc are found for highly abundant marine invertebrates. Yet, the influences of new mutations on π relative to extrinsic processes such as Nc fluctuations are unknown. Here, we provide the first germline mutation rate (µ) estimate for a marine invertebrate in corallivorous crown-of-thorns sea stars (Acanthaster cf. solaris). We use high-coverage whole-genome sequencing of 14 parent-offspring trios alongside empirical estimates of Nc in Australia's Great Barrier Reef to jointly examine the determinants of π in populations undergoing extreme Nc fluctuations. The A. cf. solaris mean µ was 9.13 x 10-09 mutations per-site per-generation (95% CI: 6.51 x 10-09 to 1.18 x 10-08), exceeding estimates for other invertebrates and showing greater concordance with vertebrate mutation rates. Lower-than-expected Ne (~70,000-180,000) and low Ne/Nc values (0.0047-0.048) indicated weak influences of population outbreaks on long-term π. Our findings are consistent with elevated µ evolving in response to reduced Ne and generation time length, with important implications for explaining high mutational loads and the determinants of genetic diversity in marine invertebrate taxa.


Assuntos
Antozoários , Animais , Antozoários/genética , Recifes de Corais , Taxa de Mutação , Mutação em Linhagem Germinativa/genética , Densidade Demográfica , Estrelas-do-Mar/genética
3.
Evol Appl ; 17(1): e13644, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38283599

RESUMO

Understanding how biodiversity originates and is maintained are fundamental challenge in evolutionary biology. Speciation is a continuous process and progression along this continuum depends on the interplay between evolutionary forces driving divergence and forces promoting genetic homogenisation. Coral reefs are broadly connected yet highly heterogeneous ecosystems, and divergence with gene flow at small spatial scales might therefore be common. Genomic studies are increasingly revealing the existence of closely related and sympatric taxa within taxonomic coral species, but the extent to which these taxa might still be exchanging genes and sharing environmental niches is unclear. In this study, we sampled extensively across diverse habitats at multiple reefs of the Great Barrier Reef (GBR) and comprehensively examined genome-wide diversity and divergence histories within and among taxa of the Stylophora pistillata species complex. S. pistillata is one of the most abundant and well-studied coral species, yet we discovered five distinct taxa, with wide geographic ranges and extensive sympatry. Demographic modelling showed that speciation events have occurred with gene flow and that taxa are at different stages along a divergence continuum. We found significant correlations between genetic divergence and specific environmental variables, suggesting that niche partitioning may have played a role in speciation and that S. pistillata taxa might be differentially adapted to different environments. Conservation actions rely on estimates of species richness, population sizes and species ranges, which are biased if divergent taxa are lumped together. As coral reefs are rapidly degrading due to climate change, our study highlights the importance of recognising evolutionarily distinct and differentially adapted coral taxa to improve conservation and restoration efforts aiming at protecting coral genetic diversity.

4.
Genome Biol Evol ; 16(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38109935

RESUMO

Human activities are accelerating rates of biological invasions and climate-driven range expansions globally, yet we understand little of how genomic processes facilitate the invasion process. Although most of the literature has focused on underlying phenotypic correlates of invasiveness, advances in genomic technologies are showing a strong link between genomic variation and invasion success. Here, we consider the ability of genomic tools and technologies to (i) inform mechanistic understanding of biological invasions and (ii) solve real-world issues in predicting and managing biological invasions. For both, we examine the current state of the field and discuss how genomics can be leveraged in the future. In addition, we make recommendations pertinent to broader research issues, such as data sovereignty, metadata standards, collaboration, and science communication best practices that will require concerted efforts from the global invasion genomics community.


Assuntos
Genômica , Espécies Introduzidas , Humanos , Clima
5.
Evol Appl ; 16(2): 293-310, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36793689

RESUMO

Genomic studies are uncovering extensive cryptic diversity within reef-building corals, suggesting that evolutionarily and ecologically relevant diversity is highly underestimated in the very organisms that structure coral reefs. Furthermore, endosymbiotic algae within coral host species can confer adaptive responses to environmental stress and may represent additional axes of coral genetic variation that are not constrained by taxonomic divergence of the cnidarian host. Here, we examine genetic variation in a common and widespread, reef-building coral, Acropora tenuis, and its associated endosymbiotic algae along the entire expanse of the Great Barrier Reef (GBR). We use SNPs derived from genome-wide sequencing to characterize the cnidarian coral host and organelles from zooxanthellate endosymbionts (genus Cladocopium). We discover three distinct and sympatric genetic clusters of coral hosts, whose distributions appear associated with latitude and inshore-offshore reef position. Demographic modelling suggests that the divergence history of the three distinct host taxa ranges from 0.5 to 1.5 million years ago, preceding the GBR's formation, and has been characterized by low-to-moderate ongoing inter-taxon gene flow, consistent with occasional hybridization and introgression typifying coral evolution. Despite this differentiation in the cnidarian host, A. tenuis taxa share a common symbiont pool, dominated by the genus Cladocopium (Clade C). Cladocopium plastid diversity is not strongly associated with host identity but varies with reef location relative to shore: inshore colonies contain lower symbiont diversity on average but have greater differences between colonies as compared with symbiont communities from offshore colonies. Spatial genetic patterns of symbiont communities could reflect local selective pressures maintaining coral holobiont differentiation across an inshore-offshore environmental gradient. The strong influence of environment (but not host identity) on symbiont community composition supports the notion that symbiont community composition responds to habitat and may assist in the adaptation of corals to future environmental change.

6.
iScience ; 25(7): 104521, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35754720

RESUMO

We investigate the genetic basis of anthropophily (human host use) in a non-model mosquito species group, the Anopheles farauti complex from the southwest Pacific. This complex has experienced multiple transitions from anthropophily to zoophily, contrasting with well-studied systems (the global species Aedes aegypti and the African Anopheles gambiae complex) that have evolved to be specialist anthropophiles. By performing tests of selection and assessing evolutionary patterns for >200 olfactory genes from nine genomes, we identify several candidate genes associated with differences in anthropophily in this complex. Based on evolutionary patterns (phylogenetic relationships, fixed amino acid differences, and structural differences) as well as results from selection analyses, we identify numerous genes that are likely to play an important role in mosquitoes' ability to detect humans as hosts. Our findings contribute to the understanding of the evolution of insect olfactory gene families and mosquito host preference as well as having potential applied outcomes.

7.
Cancers (Basel) ; 14(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35267490

RESUMO

In the last decade, targeting membrane lipids in cancer cells has been a promising approach that deserves attention in the field of anticancer drug development. To get a comprehensive understanding of the effect of the drug [Ru(η5-Cp)(PPh3)2CN] (RuCN) on cell lipidic components, we combine complementary analytical approaches, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) and synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy. Techniques are used for screening the effect of potential metallodrug, RuCN, without and with drug carriers (carbon dots (CDs) and nitrogen-doped carbon dots (N-CDs)) on the lipids of the human ovarian cancer cell line A2780. MALDI TOF MS results revealed that the lysis of ovarian cancer membrane lipids is promoted by RuCN and not by drug carriers (CDs and N-CDs). Furthermore, SR-FTIR results strongly suggested that the phospholipids of cancer cells undergo oxidative stress after the treatment with RuCN that was accompanied by the disordering of the fatty acid chains. On the other hand, using (N-)CDs as RuCN nanocarriers prevented the oxidative stress caused by RuCN but did not prevent the disordering of the fatty acid chain packing. Finally, we demonstrated that RuCN and RuCN/(N-)CDs alter the hydration of the membrane surface in the membrane-water interface region.

8.
Mol Ecol Resour ; 21(8): 2629-2644, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33448666

RESUMO

We present DILS, a deployable statistical analysis platform for conducting demographic inferences with linked selection from population genomic data using an Approximate Bayesian Computation framework. DILS takes as input single-population or two-population data sets (multilocus fasta sequences) and performs three types of analyses in a hierarchical manner, identifying: (a) the best demographic model to study the importance of gene flow and population size change on the genetic patterns of polymorphism and divergence, (b) the best genomic model to determine whether the effective size Ne and migration rate N, m are heterogeneously distributed along the genome (implying linked selection) and (c) loci in genomic regions most associated with barriers to gene flow. Also available via a Web interface, an objective of DILS is to facilitate collaborative research in speciation genomics. Here, we show the performance and limitations of DILS by using simulations and finally apply the method to published data on a divergence continuum composed by 28 pairs of Mytilus mussel populations/species.


Assuntos
Fluxo Gênico , Genoma , Teorema de Bayes , Especiação Genética , Genética Populacional , Genômica , Modelos Genéticos , Densidade Demográfica , Seleção Genética
10.
J Evol Biol ; 34(1): 175-192, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33251632

RESUMO

Non-native species experience novel selection pressures in introduced environments and may interbreed with native lineages. Species introductions therefore provide opportunities to investigate repeated patterns of adaptation and introgression across replicated contact zones. Here, we investigate genetic parallelism between multiple introduced populations of the invasive marine mussel, Mytilus galloprovincialis, in the absence (South Africa and California) and presence of hybridization with a native congener (Mytilus planulatus in Batemans Bay and Sydney Harbour, Australia). Repeatability in post-introduction differentiation from native-range populations varied between genetically distinct Atlantic and Mediterranean lineages, with Atlantic-derived introductions displaying high differentiation (maxFST  > 0.4) and parallelism at outlier loci. Identification of long noncoding RNA transcripts (lncRNA) additionally allowed us to clarify that parallel responses are largely limited to protein-coding loci, with lncRNAs likely evolving under evolutionary constraints. Comparisons of independent hybrid zones revealed differential introgression most strongly in Batemans Bay, with an excess of M. galloprovincialis ancestry and resistance to introgression at loci differentiating parental lineages (M. planulatus and Atlantic M. galloprovincialis). Additionally, contigs putatively introgressed with divergent alleles from a closely related species, Mytilus edulis, showed stronger introgression asymmetries compared with genome-wide trends and also diverged in parallel in both Atlantic-derived introductions. These results suggest that divergent demographic histories experienced by introduced lineages, including pre-introduction introgression, influence contemporary admixture dynamics. Our findings build on previous investigations reporting contributions of historical introgression to intrinsic reproductive architectures shared between marine lineages and illustrate that interspecific introgression history can shape differentiation between colonizing populations and their hybridization with native congeners.


Assuntos
Evolução Biológica , Bivalves/genética , Introgressão Genética , Espécies Introduzidas , Animais , Bivalves/metabolismo , Fluxo Gênico , RNA Longo não Codificante/metabolismo , Transcriptoma
11.
Talanta ; 222: 121551, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33167254

RESUMO

We studied the possibility of detection of [Ru(η5-C5H5)(PPh3)2Cl] (abbreviated by RuCp) complex as a model system for Ru-based metallodrugs in human urine by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) without previous purification or removal of inorganic salts. Inorganic salts might prevent the detection of RuCp by MALDI-TOF MS, most likely through the increased number and intensity of background/organic matrix signals. This problem might be overcome by the acquisition of matrix-free spectra and the addition of nanoparticles, such as carbon dots, to the urine solution. Our results suggest that RuCp is easily detectable by MALDI-TOF MS in all acquisition conditions, with the CHCA matrix being the best for acquisition in phosphate-containing solutions, whereas in urine, DHB and matrix-free approach demonstrated the highest sensitivity, precision, and reproducibility. The sensitivity of matrix-free MALDI detection of RuCp could be increased by the addition of carbon dots to the urine. Based on theoretical calculations for all matrix/analyte combinations, the model for the interaction of RuCp with carbon dots was established, and higher sensitivity explained.


Assuntos
Carbono , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Evol Appl ; 13(3): 515-532, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32431733

RESUMO

Introduced species can impose profound impacts on the evolution of receiving communities with which they interact. If native and introduced taxa remain reproductively semi-isolated, human-mediated secondary contact may promote genetic exchange across newly created hybrid zones, potentially impacting native genetic diversity and invasive species spread. Here, we investigate the contributions of recent divergence histories and ongoing (post-introduction) gene flow between the invasive marine mussel, Mytilus galloprovincialis, and a morphologically indistinguishable and taxonomically contentious native Australian taxon, Mytilus planulatus. Using transcriptome-wide markers, we demonstrate that two contemporary M. galloprovincialis introductions into south-eastern Australia originate from genetically divergent lineages from its native range in the Mediterranean Sea and Atlantic Europe, where both introductions have led to repeated instances of admixture between introduced and endemic populations. Through increased genome-wide resolution of species relationships, combined with demographic modelling, we validate that mussels sampled in Tasmania are representative of the endemic Australian taxon (M. planulatus), but share strong genetic affinities to M. galloprovincialis. Demographic inferences indicate late-Pleistocene divergence times and historical gene flow between the Tasmanian endemic lineage and northern M. galloprovincialis, suggesting that native and introduced taxa have experienced a period of historical isolation of at least 100,000 years. Our results demonstrate that many genomic loci and sufficient sampling of closely related lineages in both sympatric (e.g. Australian populations) and allopatric (e.g. northern hemisphere Mytilus taxa) ranges are necessary to accurately (a) interpret patterns of intraspecific differentiation and to (b) distinguish contemporary invasive introgression from signatures left by recent divergence histories in high dispersal marine species. More broadly, our study fills a significant gap in systematic knowledge of native Australian biodiversity and sheds light on the intrinsic challenges for invasive species research when native and introduced species boundaries are not well defined.

13.
Mol Ecol ; 29(3): 519-535, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31850605

RESUMO

Investigating the history of natural selection among closely related species can elucidate how genomes diverge in response to disparate environmental pressures. Molecular evolutionary approaches can be integrated with knowledge of gene functions to examine how evolutionary divergence may affect ecologically relevant traits such as temperature tolerance and species distribution limits. Here, we integrate transcriptome-wide analyses of molecular evolution with knowledge from physiological studies to develop hypotheses regarding the functional classes of genes under positive selection in one of the world's most widespread invasive species, the warm-tolerant marine mussel Mytilus galloprovincialis. Based on existing physiological information, we test the hypothesis that genomic functions previously linked to divergent temperature adaptation at the whole-organism level show accelerated molecular divergence between warm-adapted M. galloprovincialis and cold-adapted congeners. Combined results from codon model tests and analyses of polymorphism and divergence reveal that divergent selection has affected genomic functions previously associated with species-specific expression responses to heat stress, namely oxidative stress defence and cytoskeletal stabilization. Examining specific loci implicated in thermal tolerance among Mytilus species (based on interspecific biochemical or expression patterns), we find close functional similarities between known thermotolerance candidate genes under positive selection and positively selected loci under predicted genomic functions (those associated with divergent expression responses). Taken together, our findings suggest a contribution of temperature-dependent selection in the molecular divergence between warm- and cold-adapted Mytilus species that is largely consistent with results from physiological studies. More broadly, this study provides an example of how independent experimental evidence from ecophysiological investigations can inform evolutionary hypotheses about molecular adaptation in closely related nonmodel species.


Assuntos
Resposta ao Choque Térmico/genética , Mytilus/genética , Seleção Genética/genética , Termotolerância/genética , Adaptação Fisiológica/genética , Animais , Análise por Conglomerados , Evolução Molecular , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Temperatura Alta , Espécies Introduzidas , Estresse Oxidativo/genética , Proteoma/genética , Proteômica/métodos , Especificidade da Espécie
14.
Biometals ; 29(5): 921-33, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27515969

RESUMO

Ruthenium compounds are highly regarded as metallo-drug candidates. Many studies have focused their attention on the interaction between ruthenium complexes with their possible biological targets. The interaction of ruthenium complexes with transport proteins, enzymes and peptides is of great importance for understanding their biodistribution and mechanism of action, therefore, the development of an anti-cancer therapy involving ruthenium complexes has recently shifted from DNA targeting towards protein targeting. With the aim of gaining insight into possible interactions between ruthenium complexes with biologically relevant proteins, we have studied the interaction of cis-dichlorobis(2,2'-bipyridyl-4,4'-dicarboxylic acid)ruthenium(II) complex [Ru(II)(dcbpy)2Cl2], which previously showed good potency in photo-dynamic chemotherapy, with bovine serum albumin (BSA), phospholipase A2 (PLA2) and glutathione (GSH). Binding constants and possible number of binding sites to mentioned proteins and peptide are investigated by ultraviolet-visible spectroscopy and Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI TOF MS). The complex binding affinities were in the following order: PLA2 > BSA > GSH. Moreover, genotoxic profile of the complex, tested on peripheral blood lymphocytes as a model system, was also promising.


Assuntos
Glutationa/química , Compostos Organometálicos/química , Fosfolipases A2/química , Rutênio/química , Soroalbumina Bovina/química , Adulto , Animais , Sítios de Ligação , Bovinos , Humanos , Linfócitos/efeitos dos fármacos , Conformação Molecular , Pâncreas/enzimologia , Fosfolipases A2/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta
15.
Anal Bioanal Chem ; 408(26): 7481-90, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27510281

RESUMO

Surface-assisted laser desorption/ionisation time-of-flight mass spectrometry (SALDI-TOF-MS) might be the method of choice for the analysis of low mass molecules (less than m/z 500). Titanium dioxide (TiO2) nanocrystals as a substrate for SALDI-TOF-MS improve the reproducibility of the signal intensities and prevent the fragmentation of some molecules upon laser irradiation, as we have previously shown. In addition, variously shaped and sized TiO2 nanocrystals/substrates for SALDI-MS could be used for quantification of small molecules, which are otherwise difficult to detect with the assistance of organic matrices. TiO2-assisted LDI-MS spectra could be acquired with excellent reproducibility and repeatability and with low detection limit. In the current study, we analysed the spectra of dexasone, citric acid, vitamin E and vitamin A acquired with TiO2 nanocrystals of various shapes and dimensions, i.e. the colloidal TiO2 nanoparticles (TiO2 NPs), TiO2 prolate nanospheroids (TiO2 PNSs) and TiO2 nanotubes (TiO2 NTs). Various shapes and dimensions of substrates were used since these factors determine desorption and ionisation processes. The homogeneity on the target plate was compared based on signal-to-noise values of peaks of interest of analysed molecules as well as the within-day and day-to-day repeatability. In summary, the obtained results show that the applicability of individual TiO2 nanocrystals depends on the analyte. Signals which are acquired with the assistance of TiO2 PNSs have the highest sensitivity and reproducibility (the smallest standard deviation), even compared with those in the LDI mode. This implies that TiO2 PNSs could also be suitable for quantitative analyses of small molecules.


Assuntos
Ácido Cítrico/análise , Dexametasona/análise , Nanopartículas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Titânio/química , Vitamina A/análise , Vitamina E/análise , Limite de Detecção , Reprodutibilidade dos Testes
16.
Dalton Trans ; 45(31): 12444-57, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27431616

RESUMO

Two new dinuclear bimetallic complexes, [{PdCl(bipy)}{µ-(pyrazine)}{PtCl(bipy)}]Cl(ClO4) (1) (bipy is 2,2'-bipyridine) and [{PdCl(en)}{µ-(pyrazine)}{PtCl(en)}]Cl(ClO4) (2) (en is ethylenediamine), have been synthesized and characterized by elemental microanalysis, IR, (1)H NMR spectroscopy and MALDI-TOF mass spectrometry. The pKa values of the coordinated water molecules of the diaqua species were determined as well. Substitution reactions of complexes (1) and (2) with thiourea (Tu), l-methionine (l-Met), l-cysteine (l-Cys), l-histidine (l-His) and guanosine-5'-monophosphate (5'-GMP) were studied under the pseudo-first order conditions as a function of nucleophile concentration and temperature. The order of reactivity of nucleophiles was: Tu > l-Met > l-Cys > l-His > 5'-GMP. Substitution reactions with Tu, l-Cys and l-His were followed by decomposition of bimetallic complexes to the corresponding substituted mononuclear complexes [Pd(N-N)(Nu)2] and [Pt(N-N)(Nu)2] (N-N = bipy, en), releasing the bridging ligand. However, the structures of starting bimetallic complexes were preserved during the reactions with l-Met and 5'-GMP. The absorption spectroscopic study of interactions of calf-thymus DNA (CT-DNA) with complexes (1), (2) and [{PdCl(bipy)}{µ-(NH2(CH2)6H2N)} {PtCl(bipy)}]Cl(ClO4) (3), has shown that all the complexes exhibit high intrinsic binding constants (Kb = 10(4)-10(5) M(-1)). DNA-ethidium bromide (DNA-EB) fluorescence was quenched after addition of complexes (1), (2) or (3), indicating displacement of intercalating EB by complexes. All complexes have shown good binding affinity to bovine serum albumin protein (BSA). Chemosensitivity of A375 (human melanoma) and HeLa (human cervical cancer) cell lines toward complexes (1), (2) and (3) was analyzed by SRB assay. Complex (1) displayed significant inhibitory effect on the growth of both cell lines.


Assuntos
Antineoplásicos , Complexos de Coordenação , Paládio , Platina , 2,2'-Dipiridil/química , 2,2'-Dipiridil/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , DNA/química , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Humanos , Paládio/química , Paládio/farmacologia , Platina/química , Platina/farmacologia , Pirazinas/química , Pirazinas/farmacologia , Soroalbumina Bovina/química
17.
Mol Biol Evol ; 33(8): 1988-2001, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27189549

RESUMO

Selection associated with competition among males or sexual conflict between mates can create positive selection for high rates of molecular evolution of gamete recognition genes and lead to reproductive isolation between species. We analyzed coding sequence and repetitive domain variation in the gene encoding the sperm acrosomal protein bindin in 13 diverse sea star species. We found that bindin has a conserved coding sequence domain structure in all 13 species, with several repeated motifs in a large central region that is similar among all sea stars in organization but highly divergent among genera in nucleotide and predicted amino acid sequence. More bindin codons and lineages showed positive selection for high relative rates of amino acid substitution in genera with gonochoric outcrossing adults (and greater expected strength of sexual selection) than in selfing hermaphrodites. That difference is consistent with the expectation that selfing (a highly derived mating system) may moderate the strength of sexual selection and limit the accumulation of bindin amino acid differences. The results implicate both positive selection on single codons and concerted evolution within the repetitive region in bindin divergence, and suggest that both single amino acid differences and repeat differences may affect sperm-egg binding and reproductive compatibility.


Assuntos
Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Espermatozoides/fisiologia , Estrelas-do-Mar/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Evolução Biológica , Códon , Evolução Molecular , Feminino , Fertilização , Masculino , Preferência de Acasalamento Animal , Filogenia , Isolamento Reprodutivo , Especificidade da Espécie , Espermatozoides/metabolismo , Estrelas-do-Mar/metabolismo
18.
Ecol Evol ; 4(9): 1567-88, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24967076

RESUMO

Reproductive compatibility proteins have been shown to evolve rapidly under positive selection leading to reproductive isolation, despite the potential homogenizing effects of gene flow. This process has been implicated in both primary divergence among conspecific populations and reinforcement during secondary contact; however, these two selective regimes can be difficult to discriminate from each other. Here, we describe the gene that encodes the gamete compatibility protein bindin for three sea star species in the genus Pisaster. First, we compare the full-length bindin-coding sequence among all three species and analyze the evolutionary relationships between the repetitive domains of the variable second bindin exon. The comparison suggests that concerted evolution of repetitive domains has an effect on bindin divergence among species and bindin variation within species. Second, we characterize population variation in the second bindin exon of two species: We show that positive selection acts on bindin variation in Pisaster ochraceus but not in Pisaster brevispinus, which is consistent with higher polyspermy risk in P. ochraceus. Third, we show that there is no significant genetic differentiation among populations and no apparent effect of sympatry with congeners that would suggest selection based on reinforcement. Fourth, we combine bindin and cytochrome c oxidase 1 data in isolation-with-migration models to estimate gene flow parameter values and explore the historical demographic context of our positive selection results. Our findings suggest that positive selection on bindin divergence among P. ochraceus alleles can be accounted for in part by relatively recent northward population expansions that may be coupled with the potential homogenizing effects of concerted evolution.

19.
Evolution ; 68(5): 1294-305, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24410379

RESUMO

Reproductive isolation--the key event in speciation--can evolve when sexual conflict causes selection favoring different combinations of male and female adaptations in different populations. Likely targets of such selection include genes that encode proteins on the surfaces of sperm and eggs, but no previous study has demonstrated intraspecific coevolution of interacting gamete recognition genes under selection. Here, we show that selection drives coevolution between an egg receptor for sperm (OBi1) and a sperm acrosomal protein (bindin) in diverging populations of a sea star (Patiria miniata). We found positive selection on OBi1 in an exon encoding part of its predicted substrate-binding protein domain, the ligand for which is found in bindin. Gene flow was zero for the parts of bindin and OBi1 in which selection for high rates of amino acid substitution was detected; higher gene flow for other parts of the genome indicated selection against immigrant alleles at bindin and OBi1. Populations differed in allele frequencies at two key positively selected sites (one in each gene), and differences at those sites predicted fertilization rate variation among male-female pairs. These patterns suggest adaptively evolving loci that influence reproductive isolation between populations.


Assuntos
Adaptação Fisiológica , Evolução Molecular , Especiação Genética , Interações Espermatozoide-Óvulo , Estrelas-do-Mar/genética , Animais , Feminino , Células Germinativas/metabolismo , Células Germinativas/fisiologia , Masculino , Modelos Genéticos , População/genética , Receptores de Superfície Celular/genética , Isolamento Reprodutivo , Seleção Genética , Estrelas-do-Mar/fisiologia
20.
Acta Clin Croat ; 51(1): 51-4, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22920001

RESUMO

The most frequent indication for surgical treatment of the knee is lesion of the meniscus. The "all inside" arthroscopic technique with bioresorptive material for meniscus lesion is becoming the most popular treatment. This prospective study included 10 patients with posterior meniscal horn lesion operatively treated at Sports Traumatology Department. The "all inside" technique was performed by intra-articular application of bioresorptive pins-Darts sticks or Meniscus Viper and bioresorptive string. Patients were followed up for 2-6 months postoperatively and graded according to the IKDC 2000 scale. All surgical treatments showed satisfactory results. Young patients with acute longitudinal peripheral lesion-posterior horn lesions, in the red-red or red-white meniscal zone, 1-2 centimeters long are most appropriate for this type of treatment. In these patients, this technique proved to be superior and free from the risk of neurovascular damage. For better authentication of this conclusion, additional prospective randomized studies should be performed.


Assuntos
Artroscopia/métodos , Traumatismos em Atletas/cirurgia , Técnicas de Sutura , Lesões do Menisco Tibial , Implantes Absorvíveis , Adolescente , Adulto , Feminino , Humanos , Masculino , Meniscos Tibiais/cirurgia , Pessoa de Meia-Idade , Ruptura , Adulto Jovem
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