Sox genes in the coral Acropora millepora: divergent expression patterns reflect differences in developmental mechanisms within the Anthozoa

Background: Sox genes encode transcription factors that function in a wide range of developmental processes across the animal kingdom. To better understand both the evolution of the Sox family and the roles of these genes in cnidarians, we are studying the Sox gene complement of the coral, Acropora millepora (Class Anthozoa).\ud \ud Results: Based on overall domain structures and HMG box sequences, the Acropora Sox genes considered here clearly fall into four of the five major Sox classes. AmSoxC is expressed in the ectoderm during development, in cells whose morphology is consistent with their assignment as sensory neurons. The expression pattern of the Nematostella ortholog of this gene is broadly similar to that of AmSoxC, but there are subtle differences – for example, expression begins significantly earlier in Acropora than in Nematostella. During gastrulation, AmSoxBb and AmSoxB1 transcripts are detected only in the presumptive ectoderm while AmSoxE1 transcription is restricted to the presumptive endoderm, suggesting that these Sox genes might play roles in germ layer specification. A third type B Sox gene, AmSoxBa, and a Sox F gene AmSoxF also have complex and specific expression patterns during early development. Each of these genes has a clear Nematostella ortholog, but in several cases the expression pattern observed in Acropora differs significantly from that reported in Nematostella.\ud \ud Conclusion: These differences in expression patterns between Acropora and Nematostella largely reflect fundamental differences in developmental processes, underscoring the diversity of mechanisms within the anthozoan Sub-Class Hexacorallia (Zoantharia)

Origem das paisagens.

Domínios geomorfológicos do Ceará. Planície costeira do Ceará. Tabuleiros costeiros. Chapada do Apodi. Chapada do Araripe. Chapada Ibiapaba. Depressão sertaneja. Depressões sedimentares em meio à superfície sertaneja. Maciços residuais cristalinos

Unexpected diversity of cnidarian integrins: expression during coral gastrulation

<p>Abstract</p> <p>Background</p> <p>Adhesion mediated through the integrin family of cell surface receptors is central to early development throughout the Metazoa, playing key roles in cell-extra cellular matrix adhesion and modulation of cadherin activity during the convergence and extension movements of gastrulation. It has been suggested that <it>Caenorhabditis elegans</it>, which has a single β and two α integrins, might reflect the ancestral integrin complement. Investigation of the integrin repertoire of anthozoan cnidarians such as the coral <it>Acropora millepora </it>is required to test this hypothesis and may provide insights into the original roles of these molecules.</p> <p>Results</p> <p>Two novel integrins were identified in <it>Acropora</it>. AmItgα1 shows features characteristic of α integrins lacking an I-domain, but phylogenetic analysis gives no clear indication of its likely binding specificity. AmItgβ2 lacks consensus cysteine residues at positions 8 and 9, but is otherwise a typical β integrin. In situ hybridization revealed that AmItgα1, AmItgβ1, and AmItgβ2 are expressed in the presumptive endoderm during gastrulation. A second anthozoan, the sea anemone <it>Nematostella vectensis</it>, has at least four β integrins, two resembling AmItgβ1 and two like AmItgβ2, and at least three α integrins, based on its genomic sequence.</p> <p>Conclusion</p> <p>In two respects, the cnidarian data do not fit expectations. First, the cnidarian integrin repertoire is more complex than predicted: at least two βs in <it>Acropora</it>, and at least three αs and four βs in <it>Nematostella</it>. Second, whereas the bilaterian αs resolve into well-supported groups corresponding to those specific for RGD-containing or laminin-type ligands, the known cnidarian αs are distinct from these. During early development in <it>Acropora</it>, the expression patterns of the three known integrins parallel those of amphibian and echinoderm integrins.</p

Compartimentação geomorfológica das bacias hidrográficas dos rios Macacu e Caceribu - Recôncavo da Baixada da Guanabara /RJ.

A geomorfologia das bacias dos rios Macacu e Caceribu revela um mosaico de paisagens condicionado pela tectônica Cenozoica e pela variação do nível relativo do mar. Sua compartimentação compreende 10 unidades geomorfológicas: escarpa da serra dos Órgãos; espigão das serras de Santana e da Botija; maciços da Região dos Lagos; maciços alcalinos de Tanguá, Rio Bonito e Soarinho; alto platô da serra dos Órgãos; superfície aplainada da Região dos Lagos; bacia de Macacu; e baixada da Baía de Guanabara

Formyltetrahydrofolate Synthetase Gene Diversity in the Guts of Higher Termites with Different Diets and Lifestyles

In this study, we examine gene diversity for formyl-tetrahydrofolate synthetase (FTHFS), a key enzyme in homoacetogenesis, recovered from the gut microbiota of six species of higher termites. The "higher" termites (family Termitidae), which represent the majority of extant termite species and genera, engage in a broader diversity of feeding and nesting styles than the "lower" termites. Previous studies of termite gut homoacetogenesis have focused on wood-feeding lower termites, from which the preponderance of FTHFS sequences recovered were related to those from acetogenic treponemes. While sequences belonging to this group were present in the guts of all six higher termites examined, treponeme-like FTHFS sequences represented the majority of recovered sequences in only two species (a wood-feeding Nasutitermes sp. and a palm-feeding Microcerotermes sp.). The remaining four termite species analyzed (a Gnathamitermes sp. and two Amitermes spp. that were recovered from subterranean nests with indeterminate feeding strategies and a litter-feeding Rhynchotermes sp.) yielded novel FTHFS clades not observed in lower termites. These termites yielded two distinct clusters of probable purinolytic Firmicutes and a large group of potential homoacetogens related to sequences previously recovered from the guts of omnivorous cockroaches. These findings suggest that the gut environments of different higher termite species may select for different groups of homoacetogens, with some species hosting treponeme-dominated homoacetogen populations similar to those of wood-feeding, lower termites while others host Firmicutes-dominated communities more similar to those of omnivorous cockroaches

Metal Hydrides and Related Materials - Energy Carriers for Novel Hydrogen and Electrochemical Storage

The seventh edition of the International Renewable and Sustainable Energy Conference (IRSEC) was held in Agadir (Sofitel Royal Bay, November 27–30, Morocco) under the Program Chair of Prof. Ahmed Ennaoui (IRESEN). IRSEC, as one of the biggest conferences in north Africa, aims at creating an international forum to facilitate discussions and exchanges in all aspects of renewable and sustainable energy. This Viewpoint will summarize the scientific presentations and stimulated discussions during the Special Session (November 28–29) on Metal Hydrides’ Energy covering topics of metal hydrides and energy related issues for innovative processes and technologies, with a focus on magnesium-based hydrides, intermetallic hydrides, complex and melt hydrides, porous materials, and thin films

Geotecnologia 3D na compartimentação geomorfológica das bacias hidrográficas dos rios Macacu e Caceribu - Recôncavo da Baixada da Guanabara /RJ.

É indiscutível o uso cada vez maior da tecnologia 3D nos mapeamentos do meio físico, incluindo a geomorfologia. Os modelos digitais de elevação somados às ortofotos de alta resolução fornecem ao intérprete um material que facilita e eleva a acurácia da fotointerpretação, produzindo excelentes resultados. Com o uso de softwares capazes de elaborar visualizações 3D, compartimentou-se as unidades de relevo das Bacias Hidrográficas dos rios Macacu e Caceribu - Recôncavo da Baixada da Guanabara/RJ

Mapeamento do uso atual e cobertura vegetal dos solos do Estado do Rio de Janeiro.

O conhecimento do uso atual e cobertura do solo é imprescindível em qualquer projeto de caracterização e monitoramento ambientais, permitindo demarcar os diferentes usos da terra e vegetação, bem como subsidiar o planejamento e gestão ambientais. O presente trabalho abrange a totalidade do Estado do Rio de Janeiro, compreendido entre os meridianos 410 e 450 de longitude Oeste e os paralelos 200 30º e 230 30º de latitude Sul, estendendo-se por aproximadamente 44.000 km2. Tem como objetivo inventariar e mapear o estado atual da ocupação dos solos, distinguindo e quantificando os principais tipos de uso do solo e de cobertura vegetal, apresentados numa escala generalizada de 1:250.000. Para tal, fez-se um mapeamento preliminar com base nos padrões espectrais das imagens de satélite Landsat ETM7+, cedidas pela EMATER-RJ, utilizando-se de diferentes algoritmos de classificação espectral. Durante a elaboração da versão final do Mapa de Uso Atual e Cobertura Vegetal dos Solos do Estado do Rio de Janeiro, foram viagens de verificação in situ a fim de esclarecer dúvidas e subsidiar ajustes e modificações posteriores. O trabalho de pré-processamento, interpretação e classificação das imagens para a produção e edição final do Mapa de Uso Atual e Cobertura Vegetal realizou-se no período de março de 2002 a fevereiro de 2003, pelas equipes técnicas da CPRM (Serviço Geológico Brasileiro), Divisão de Geoprocessamento - DIGEOP, Departamento de Informações Institucionais (DEINF) e o Laboratório de Geoinformação da Embrapa Solos. Foram identificadas e mapeadas 13 grandes classes de uso e ocupação do solo, algumas delas subdivididas em tipos, assim classificadas e distribuídas: 1 - Mata Atlântica (Remanescente/Secundária e Ciliar); 2 - Mangue (Mangue e Mangue Degradado); 3 - Restinga; 4 - Pecuária (Pastagem Plantada e Campo / Pastagem em Zona Úmida); 5 - Agricultura; 6 - Reflorestamento; 7 - Afloramento de Rocha; 8 - Solo Exposto; 9 - Corpo d'Água; 10 - Salina; 11 - Extração de Areia / Mineração; 12 - Praia e Duna; 13 - Área Urbana.bitstream/CNPS/11606/1/bpd22_2003_mapeamento_rj.pd

Geomorfologia das bacias dos rios Guapi-Macacu e Caceribu - recôncavo da Baía de Guanabara - Estado do Rio de Janeiro.

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