Species boundary and extensive hybridization and introgression in Petunia

Studying the role of hybridization in the speciation of plants is one of the most thrilling areas of evolutionary biology. Hybridization in natural populations can act in opposition to divergence, contribute to adaptation through introgression or foster the emergence of new lineages via hybrid speciation. Species of the plant genus Petunia grow in open areas in southern South America. Some natural interspecific hybrid events have been described for the genus, such as between the endemic P. exserta and the widespread P. axillaris. Both species occur in sympatry in Serra do Sudeste (Brazil), where they occur in diverse habitats and exhibit floral divergence, which has been related to the attraction of different primary pollinators. The present study evaluates the maintenance of the species boundaries front of hybridization and introgression. Direct and indirect methods of estimating gene exchange employed genotyping 720 reproductive plants and 611 progenies of both species with eight microsatellite loci. Gene exchange was found to be frequent and bidirectional between the species, indicating that introgression changes their genetic constitution in areas of sympatry. Limits of the studied species are being maintained because of the high level of inbreeding and backcrosses that are habitat-dependent

What could be the fate of secondary contact zones between closely related plant species?

Interspecific hybridization has been fundamental in plant evolution. Nevertheless, the fate of hybrid zones throughout the generations remains poorly addressed. We analyzed a pair of recently diverged, interfertile, and sympatric Petunia species to ask what fate the interspecific hybrid population has met over time. We analyzed the genetic diversity in two generations from two contact sites and evaluated the effect of introgression. To do this, we collected all adult plants from the contact zones, including canonicals and intermediary colored individuals, and compared them with purebred representatives of both species based on seven highly informative microsatellite loci. We compared the genetic diversity observed in the contact zones with what is seen in isolated populations of each species, considering two generations of these annual species. Our results have confirmed the genetic differentiation between the species and the hybrid origin of the majority of the intermediary colored individuals. We also observed a differentiation related to genetic variability and inbreeding levels among the populations. Over time, there were no significant differences per site related to genetic diversity or phenotype composition. We found two stable populations kept by high inbreeding and backcross rates that influence the genetic diversity of their parental species through introgression

Could the reproductive system explain the stability and long-term persistence in a natural hybrid zone of Petunia (Solanaceae)?

The long-term success of populations is dependent on individual reproductive success, and in general, increased population size and genetic diversity contribute to population maintenance, reducing the risk of local extinction. Interspecific hybridization has consequences that can vary according to the hybrids' fate, which can be strongly influenced by the reproductive capacity of hybrids and canonical individuals from the contact zone. We examined the reproductive biology and morphology of two closely related Petunia (Solanaceae) species and their interspecific hybrids from Serra do Sudeste, Southern Brazil, and we measured their reproductive success under controlled conditions based on seed production and germination from five pollination treatments. We found differences in self-compatibility degree among individuals, lineages, and pollination treatments based on high total seed production (> 204,000 seeds) and germination (630 seedlings evaluated). No correlation was observed between corolla colour and reproductive success or between floral morphological traits and compatibility. High self-compatibility and inter-lineage compatibility can explain the hybrid populations' maintenance and origin, favouring the two analysed species' introgression

Diversification in the South American Pampas: the genetic and morphological variation of the widespread Petunia axillaris complex (Solanaceae)

Understanding the spatiotemporal distribution of genetic variation and the ways in which this distribution is connected to the ecological context of natural populations is fundamental for understanding the nature and mode of intraspecific and, ultimately,interspecific differentiation. The Petunia axillaris complex is endemic to the grasslands of southern South America and includes three subspecies: P. a. axillaris, P. a. parodii and P. a. subandina. These subspecies are traditionally delimited based on both geography and floral morphology, although the latter is highly variable. Here, we determined the patterns of genetic (nuclear and cpDNA), morphological and ecological (bioclimatic) variation of a large number of P. axillaris populations and found that they are mostly coincident with subspecies delimitation. The nuclear data suggest that the subspecies are likely independent evolutionary units, and their morphological differences may be associated with local adaptations to diverse climatic and/or edaphic conditions and population isolation. The demographic dynamics over time estimated by skyline plot analyses showed different patterns for each subspecies in the last 100 000 years, which is compatible with a divergence time between 35 000 and 107 000 years ago between P. a. axillaris and P. a. parodii, as estimated with the IMa program. Coalescent simulation tests using Approximate Bayesian Computation do not support previous suggestions of extensive gene flow between P. a. axillaris and P. a. parodii in their contact zone.Fil: Turchetto, Caroline. Universidade Federal Do Rio Grande Do Sul; Brasil;Fil: Fagundes, Nelson J. R.. Universidade Federal Do Rio Grande Do Sul; Brasil;Fil: Segatto, Ana L. A.. Universidade Federal Do Rio Grande Do Sul; Brasil;Fil: Kuhlemeier, Cris. Institute of Plant Science; Suiza;Fil: Solis Neffa, Viviana Griselda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); ArgentinaFil: Speranza, Pablo R. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); ArgentinaFil: Bonatto, Sandro L.. Pontificia Universidade Catolica Do Rio Grande Do Sul; Brasil;Fil: Freitas, Loreta B.. Universidade Federal Do Rio Grande Do Sul; Brasil

O USO DO QUANTUM GIS (QGIS) PARA CARACTERIZAÇÃO E DELIMITAÇÃO DE ÁREA DEGRADA POR ATIVIDADE DE MINERAÇÃO DE BASALTO NO MUNICÍPIO DE TENTENTE PORTELA (RS)

The rise construction developed an accelerated process of extracting rock , increasing the number and extent of the quarries are in Brazil . This activity of extracting rock causes several changes in the environment , monitoring of these degraded areas through the use of environmental zoning is required. To monitor the extraction of basalt from the municipality of Tenente Portela ( RS ) mine , we used to use Quantum GIS ( QGIS ) software to characterize the area , effecting the delimitation of the area of mining digging and regions deposit tailings , access roads and points of interest in the area in question . For each contour were nominated for best viewing points on the boundaries . The Quantum GIS software is shown , using the tools offered by them for handling spatial data , a good geotechnical method to aid in planning the recovery of degraded area because the software offer data collection mechanisms that facilitate the study of the state of area in question .A ascensão da construção civil desenvolve um processo acelerado de extração de rochas, aumentando o número e a extensão de pedreiras no Brasil. Essa atividade de extração de rochas causa inúmeros problemas sociais, econômicos e principalmente ambientais, sendo necessário o monitoramento dessas áreas degradadas através do uso do zoneamento ambiental. O foco central desse trabalho na mina de extração de Basalto do Município de Tenente Portela consiste no zoneamento ambiental através do uso do software Quantum Gis (QGIS) para a caracterização da área da cava de extração, bem como a delimitação das regiões de depósito de rejeitos, as vias de acesso e pontos de interesse na área em questão. Para cada delimitação foram nomeados pontos para melhor visualização das áreas. Os resultados apontam que o software Quantum Gis mostra-se um programa excelente para manipulação de dados espaciais, e também um bom método geotécnico, por apresentar mecanismos de levantamento de dados, no auxílio do planejamento de recuperação da área degrada em questão.

Molecular evolution and diversification of the GRF transcription factor family

Growth Regulating Factors (GRFs) comprise a transcription factor family with important functions in plant growth and development. They are characterized by the presence of QLQ and WRC domains, responsible for interaction with proteins and DNA, respectively. The QLQ domain is named due to the similarity to a protein interaction domain found in the SWI2/SNF2 chromatin remodeling complex. Despite the occurrence of the QLQ domain in both families, the divergence between them had not been further explored. Here, we show evidence for GRF origin and determined its diversification in angiosperm species. Phylogenetic analysis revealed 11 well-supported groups of GRFs in flowering plants. These groups were supported by gene structure, synteny, and protein domain composition. Synteny and phylogenetic analyses allowed us to propose different sets of probable orthologs in the groups. Besides, our results, together with functional data previously published, allowed us to suggest candidate genes for engineering agronomic traits. In addition, we propose that the QLQ domain of GRF genes evolved from the eukaryotic SNF2 QLQ domain, most likely by a duplication event in the common ancestor of the Charophytes and land plants. Altogether, our results are important for advancing the origin and evolution of the GRF family in Streptophyta

Alimentação Automatizada para Pets/ Automated Feeding for Pets

Na contemporaneidade, a sociedade vem aderindo cada vez mais animais domésticos e possuindo menos tempo para cuidar dos mesmos. Assim torna-se necessário a criação de tecnologias, que supram as necessidades do pet e, também do seu responsável. Com o intuito de atender essa carência desenvolvemos um Alimentador Automático para Pets (AAP), pensando em automatizar o processo de alimentação dos animais, com um projeto de fácil manuseio e bom custo benefício

Elp3-mediated codon-dependent translation promotes mTORC2 activation and regulates macrophage polarization.

peer reviewedMacrophage polarization is a process whereby macrophages acquire distinct effector states (M1 or M2) to carry out multiple and sometimes opposite functions. We show here that translational reprogramming occurs during macrophage polarization and that this relies on the Elongator complex subunit Elp3, an enzyme that modifies the wobble uridine base U34 in cytosolic tRNAs. Elp3 expression is downregulated by classical M1-activating signals in myeloid cells, where it limits the production of pro-inflammatory cytokines via FoxO1 phosphorylation, and attenuates experimental colitis in mice. In contrast, alternative M2-activating signals upregulate Elp3 expression through a PI3K- and STAT6-dependent signaling pathway. The metabolic reprogramming linked to M2 macrophage polarization relies on Elp3 and the translation of multiple candidates, including the mitochondrial ribosome large subunit proteins Mrpl3, Mrpl13, and Mrpl47. By promoting translation of its activator Ric8b in a codon-dependent manner, Elp3 also regulates mTORC2 activation. Elp3 expression in myeloid cells further promotes Wnt-driven tumor initiation in the intestine by maintaining a pool of tumor-associated macrophages exhibiting M2 features. Collectively, our data establish a functional link between tRNA modifications, mTORC2 activation, and macrophage polarization

Estrutura genética e diversificação de plantas no pampa : estudos de caso em petunia (SOLANACEAE)

O Pampa, localizado na porção sul do Neotrópico, é uma vasta região de terras baixas compostas principalmente por gramíneas, possivelmente constituindo a ecorregião menos estudada no sul da América do Sul. Constituído de uma paisagem heterogênea, o Pampa abriga uma rica biodiversidade com muitas espécies endêmicas. Entretanto, o conhecimento sobre o padrão de distribuição geográfica e evolução de plantas que ocorrem nessa área ainda é escasso. O objetivo do presente trabalho foi gerar dados moleculares e avaliar diferentes interações ecológicas nas espécies do gênero Petunia (Solanaceae), que ocorrem no Pampa, através do uso de marcadores moleculares (microssatélites nucleares e sequenciamento de regiões do cloroplasto), e morfológicos. Contribuindo assim, para o conhecimento dos processos de diversificação e especiação de plantas do Pampa, bem como da história evolutiva do gênero Petunia. Para isto foram conduzidos experimentos de caracterização da diversidade genética e morfológica em populações naturais cujos resultados foram avaliados com metodologias de análise filogeográfica, populacional e de fluxo gênico. Os resultados foram descritos em detalhes nos seis artigos científicos que compõem a Tese e podem ser assim resumidos. A rápida radiação dos gêneros Petunia e Calibrachoa demonstra como a forte pressão seletiva para diferentes polinizadores, juntamente com adaptação a diferenças edáficas e climáticas, pode constituir o fator chave envolvido na diversificação de plantas nos Pampas. Petunia axillaris é um bom exemplo disso, pois as diferenças nos caracteres florais que discriminam taxonomicamente as três subespécies deste complexo são o resultado das adaptações a fatores ecológicos (diferenças de solo e polinizadores) e representam linhagens evolutivas e não meramente plasticidade fenotípica. Nós também encontramos que P. axillaris subsp. axillaris apresenta altos níveis de auto-polinização numa região simpátrica com P. exserta, e nós sugerimos que isto pode ser um mecanismo de prevenção contra formação de híbridos com esta espécie, visto que este mecanismo têm sido documentado nos últimos anos. Esses resultados estão de acordo com nossos achados de baixa incidência de híbridos nas zonas de contato entre essas duas espécies, onde possivelmente atuam mecanismos de isolamento reprodutivo bem como forte seleção que mantém os limites dessas espécies, como diferentes polinizadores e microhabitats específicos. Surpreendentemente, nós encontramos altos níveis de diversidade em P. 8 secreta, uma espécie irmã de P. exserta e P. axillaris, e que dentre as três é a que apresenta maior diferenciação genética. Em conclusão, nossos resultados mostram que essas três espécies de Petunia do Pampa apresentam acentuada diferenciação genética e que os processos de especiação realmente podem ser relacionados a adaptações ecológicas. Embora os mecanismos de isolamento reprodutivo não tenham sido conclusivos por completo, estratégias de isolamento reprodutivo podem ser encontradas nessas espécies e podem ser responsáveis pela sua manutenção como taxa independentes.The Pampas, located in the southern portion of the Neotropic, is a wide region of lowlands with vegetation composed mainly of grasses, being possibly the ecoregion less studied in South America. It is constituted of a heterogeneous landscape and harbors a rich biodiversity with many endemic species. However, the knowledge about the geographic distribution and evolution of plants that occur in the Pampas region is still scarce. The objective of this work was to generate molecular data and evaluate the ecological interactions among species of the genus Petunia (Solanaceae) that occur on the Pampas using molecular markers (nuclear microsatellites and plastid sequences) and morphological traits. With this we intent to contribute to the knowledge of the Pampas plant diversification and speciation processes, as well as on the evolutionary history of the genus Petunia. Genetic and morphological variability were characterized in natural populations and the results were evaluated with methods including phylogeographic, population genetics, and gene flow approaches. Results were described in detail on six scientific articles that compose this thesis and can be summarized as follow. The rapid radiation of the genera Petunia and Calibrachoa demonstrate how strong selective pressure to different pollinators together with the adaptation to edaphic and climatic differences can constitute key factors in the diversification of plants in the Pampas. Petunia axillaris is a good example of this. The differences in floral characteristics that differentiate its three subspecies are adaptations to ecological factors (soil and pollinators differences) and represents evolutionary lineages and not merely phenotypic plasticity. We also found that Petunia axillaris subsp. axillaris presents high levels of self-pollination in a sympatric region with Petunia exserta and we suggest this could be a mechanism to prevent hybridization, which has been documented in the last years. The results are in accordance with our findings of few hybrids individuals in the contact zones of P. exserta and P. axillaris, which probably act mechanisms of reproductive isolation and strong selection that keeps the limits of these species, as different pollinators and specific microhabitats. Surprisingly we found high levels of genetic diversity in P. secreta, a rare species sister to P. exserta and P. axillaris. Considering these three related species, P. secreta is genetically most differentiated. In conclusion, our results demonstrate that species of the Petunia from the Pampas show accentuate genetic differentiation and that the speciation processes could be related to ecological adaptations. Even though the mechanisms of reproductive isolation were not completely conclusive, reproductive isolation strategies are found in these species and guarantee their maintenance as independent taxa