Hox and ParaHox genes are groups of key developmental transcription factors that are highly conserved throughout the Metazoa. Their order of expression along the body axis of an animal is not only highly conserved between different organisms, but is also collinear to the arrangement of individual genes along the chromosome. Studies of these developmental control genes can give valuable insights into the evolution of body plans. A total of 7 homeobox containing genes (<I>dpl1-dpl7</I>) were isolated form the <I>D. listerianum </I> genome. Four of these were members of the <I>Hox</I> gene family and of the <I>ParaHox </I>gene family. Initial fragments were isolated using the method of degenerate PCR with primers designed from the highly conserved amino acid sequence of the 1^st and 3^rd helix of the homeodomain. Short fragments limit gene characterisation and as such, regions flanking the degenerate PCR products were isolated, using inverse PCR, 3' and 5' RACE PCR. Phylogenetic relationships of the genes are also examined. <I>Dpl1</I> exhibited high identities with the arthropod <I>Antennapedia</I> and the vertebrate <I>Hox6 </I>and <I>Hox 7</I> paralogue groups. Phylogenetic analysis showed dpl1 to be more closely related to the Hox6 than to the Hox7 group genes. <I>Dpl2 </I>shares high identity with members of the <I>Hox5/Scr </I>paralogous group. <I>Dpl3</I> has a high level of homology to the <I>C. intestinalis</I> gene <I>CiIPF1</I>. The <I>Dpl3 </I>homeodomain shared high identity with the ascidian <I>H. roretzi</I> and <I>H. curvata </I>cdx genes (<I>Hr-cad</I> and <I>Hec-cdx</I>, respectively), however differences in the hexapeptide regions, indicated high divergence of these genes in the ascidians. <I>Dpl5</I> possessed features characteristic of posterior Hox genes and was most closely related to the <I>C. intestinalis</I> <I>CiHbox5</I> gene. <I>Dpl6</I> shared features common to the Hox 4 paralogous group Gsx ParaHox groups.

Embora tenham sido muito estudadas em diversos pontos do globo, as ascídias do litoral brasileiro são pouco conhecidas. A maior parte do litoral brasileiro está incluída na região tropical, para qual as informações são mais escassas. Com o intuito de se conhecer a fauna de ascídias do litoral tropical brasileiro foram realizadas diversas coletas em diferentes pontos desta região, abrangendo desde a zona entremarés até o infralitoral raso. Outro objetivo do presente trabalho foi o de organizar as informações já existentes a partir de revisão bibliográfica e visitas a algumas instituições que continham coleções representativas. Foram realizadas ao todo 61 coletas em pontos distribuídos entre os estados do Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Os animais foram coletados, examinados e identificados até o nível de espécie. Para cada espécie se procurou fazer um extensa revisão taxonômica, tanto a partir da literatura como do exame de tipos depositados em diferentes instituições. O presente trabalho inclui listas sinonímicas, descrições e comentários para cada espécie estudada, com fotografias para a maior parte. Foram adicionadas ainda chaves dicotômicas para todos os táxons, em todas as categorias. Até a realização deste trabalho, 90 espécies de ascídias haviam sido registradas no litoral brasileiro, das quais 54 estão listadas para o estado de São Paulo. Com a realização das campanhas de coletas foram identificadas 67 espécies que, juntamente com uma revisão criteriosa da literatura e o exame de vários tipos e outros exemplares de outras regiões do mundo, fizeram com que a lista atualizada inclua 98 espécies. Estas espécies estão distribuídas entre as 2 ordens e 3 subordens da classe, com um total de 31 gêneros incluídos em 14 dentre as 23 famílias propostas atualmente. Como resultado imediato foram registradas 9 novas ocorrências para o litoral brasileiro, com a descrição de 1 gênero e 10 espécies novas. Além disso, 8 espécies tiveram sua situação alterada por sinonimia ou separação. Juntamente com outros dados da literatura, as tabelas de ocorrências foram submetidas a uma análise de agrupamento e uma análise de endemicidade por parcimônia. As análises evidenciaram um padrão de distribuição semelhante àquele observado para outros grupos bentônicos sésseis, com a divisão da região estudada em duas províncias, a Província Brasileira e a Província Paulista. / Although ascidians are well known in many regions of the globe, information about the group on Brazilian coast are very scanty. Most of the Brazilian coastline is included on the tropical region, which is the poorest known. In order to obtain an inventory of ascidians species on the Brazilian tropical coast, surveys were conducted in different points, ranging from the intertidal to the shallow subtidal depths. Another goal of the present work was to organize all available information through a revision of bibliography and visits to institutions that held representative collections. 61 visits were conducted in places along the coast of the states of Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Specimens were collected, examined and identified to the species level. An extensive taxonomic revision was made for every species, by means of literature as well as examination of types and other specimens deposited in different institutions. The present work includes synonymy lists, descriptions, pictures and remarks for each species studied. Keys for all taxa an every category were also included. Up to the present work, 90 species of ascidians had been recorded for Brazil, of which 54 are listed to the State of São Paulo. The surveys revealed a total of 67 species, expanding the list to 98 Brazilian species. Those species are distributed in 2 orders and 3 suborders of the class, with a total of 31 genera included in 14 of the 23 families currently accepted. As an immediate result, were registered 9 new records for Brazilian coast, along with the description of 1 new genus and 10 new species. Furthermore, 8 species have had its taxonomic situation altered by synonymy or separation. The present results, together with data from literature generated tables which were submitted to cluster analysis and a parsimony analysis of endemycity. These analyses revealed a distribution pattern similar to others observed for different benthic taxa. The region studied comprises two provinces, Brazilian Province and Paulista Province.

Embora tenham sido muito estudadas em diversos pontos do globo, as ascídias do litoral brasileiro são pouco conhecidas. A maior parte do litoral brasileiro está incluída na região tropical, para qual as informações são mais escassas. Com o intuito de se conhecer a fauna de ascídias do litoral tropical brasileiro foram realizadas diversas coletas em diferentes pontos desta região, abrangendo desde a zona entremarés até o infralitoral raso. Outro objetivo do presente trabalho foi o de organizar as informações já existentes a partir de revisão bibliográfica e visitas a algumas instituições que continham coleções representativas. Foram realizadas ao todo 61 coletas em pontos distribuídos entre os estados do Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Os animais foram coletados, examinados e identificados até o nível de espécie. Para cada espécie se procurou fazer um extensa revisão taxonômica, tanto a partir da literatura como do exame de tipos depositados em diferentes instituições. O presente trabalho inclui listas sinonímicas, descrições e comentários para cada espécie estudada, com fotografias para a maior parte. Foram adicionadas ainda chaves dicotômicas para todos os táxons, em todas as categorias. Até a realização deste trabalho, 90 espécies de ascídias haviam sido registradas no litoral brasileiro, das quais 54 estão listadas para o estado de São Paulo. Com a realização das campanhas de coletas foram identificadas 67 espécies que, juntamente com uma revisão criteriosa da literatura e o exame de vários tipos e outros exemplares de outras regiões do mundo, fizeram com que a lista atualizada inclua 98 espécies. Estas espécies estão distribuídas entre as 2 ordens e 3 subordens da classe, com um total de 31 gêneros incluídos em 14 dentre as 23 famílias propostas atualmente. Como resultado imediato foram registradas 9 novas ocorrências para o litoral brasileiro, com a descrição de 1 gênero e 10 espécies novas. Além disso, 8 espécies tiveram sua situação alterada por sinonimia ou separação. Juntamente com outros dados da literatura, as tabelas de ocorrências foram submetidas a uma análise de agrupamento e uma análise de endemicidade por parcimônia. As análises evidenciaram um padrão de distribuição semelhante àquele observado para outros grupos bentônicos sésseis, com a divisão da região estudada em duas províncias, a Província Brasileira e a Província Paulista. / Although ascidians are well known in many regions of the globe, information about the group on Brazilian coast are very scanty. Most of the Brazilian coastline is included on the tropical region, which is the poorest known. In order to obtain an inventory of ascidians species on the Brazilian tropical coast, surveys were conducted in different points, ranging from the intertidal to the shallow subtidal depths. Another goal of the present work was to organize all available information through a revision of bibliography and visits to institutions that held representative collections. 61 visits were conducted in places along the coast of the states of Rio de Janeiro, Espírito Santo, Bahia, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte e Ceará. Specimens were collected, examined and identified to the species level. An extensive taxonomic revision was made for every species, by means of literature as well as examination of types and other specimens deposited in different institutions. The present work includes synonymy lists, descriptions, pictures and remarks for each species studied. Keys for all taxa an every category were also included. Up to the present work, 90 species of ascidians had been recorded for Brazil, of which 54 are listed to the State of São Paulo. The surveys revealed a total of 67 species, expanding the list to 98 Brazilian species. Those species are distributed in 2 orders and 3 suborders of the class, with a total of 31 genera included in 14 of the 23 families currently accepted. As an immediate result, were registered 9 new records for Brazilian coast, along with the description of 1 new genus and 10 new species. Furthermore, 8 species have had its taxonomic situation altered by synonymy or separation. The present results, together with data from literature generated tables which were submitted to cluster analysis and a parsimony analysis of endemycity. These analyses revealed a distribution pattern similar to others observed for different benthic taxa. The region studied comprises two provinces, Brazilian Province and Paulista Province.

Biologically active compounds isolated from marine sources have had increasing interest in recent years with significant research going into the discovery and isolation of novel marine polysulfide natural products. Varacin, probably the most widely studied marine polysulfide to date was the subject of much debated structure elucidation attempts, and more recently several successful synthetic approaches have been published. The work published aims to increase our understanding of marine polysulfide compounds existence in nature and determine the origins of their biological activity. (+)-Aplidium trisulfide which was isolated from Aplidium Sp. D in 1989 by Munro et al has been shown to exhibit in vitro antimicrobial, antileukemic and cytotoxic properties. These intriguing biological effects have led our work towards developing a novel synthetic route toward aplidium trisulfide by both chiral and racemic routes. Aplidium trisulfide is of special significance as it is very rare to isolate enantiomeric compounds from marine sources. Two other closely related marine alkaloids fasmerianamine A and B are also of synthetic interest to us due to their close resemblance to the structure of aplidium trisulfide. The fasmerianamines were isolated by Copp et al from the marine ascidian Hypsistozoa fasmeriana in 2001.

The simultaneous increase in biological invasions and habitat alteration through the building of coastal infrastructure is playing an important role in reshaping the composition and functioning of nearshore marine ecosystems. This thesis examined patterns of marine invasions across anthropogenic and natural habitats and explored some of the processes that influence establishment and spread of invaders. The goals of this thesis were four-fold. First, I examined the habitat distribution of marine nonindigenous species (NIS) spanning several taxonomic groups and geographical regions. Second, I conducted systematic subtidal surveys in anthropogenic and natural habitats and investigated the distribution of nonindigenous ascidians on Southern Vancouver Island, British Columbia, Canada. Third, I tested methods for in-situ larval inoculations and utilized these techniques to manipulate propagule supply and assess post-settlement mortality of ascidians across habitat types. Fourth, I investigated the role of biotic resistance, through predation by native species, on the survival of ascidian colonies in anthropogenic and natural habitats. Results from this research showed that anthropogenic habitats are hubs for marine invasions and may provide beachheads for the infiltration of nearby natural sites. Specifically, a literature review of global scope showed that most NIS are associated with anthropogenic habitats, but this pattern varied by taxonomic group. Most algal and mobile invertebrate NIS were reported from natural habitats, while most sessile NIS were reported from artificial structures. Subtidal field surveys across both anthropogenic and natural habitats showed that nonindigenous ascidians were restricted largely to artificial structures on Southern Vancouver Island and that this pattern is consistent across their global introduced ranges. Field manipulations using the ascidian Botrylloides violaceus as a model organism, showed that post-settlement mortality is high and that large numbers of larvae or frequent introduction events may be needed for successful initial invasion and successful infiltration of natural habitats. Experiments also showed that predation by native species can limit the survival of B. violaceus in anthropogenic and natural habitats. This dissertation contributes knowledge about the patterns and processes associated with habitat invisibility; provides insight into factors affecting colonization; and supplies valuable information for predicting and managing invasions. / Graduate / 0329

Amostras de Didemnum psammatodes foram coletadas em Icapuí (CE) e Trairi (CE). O extrato metanólico de D. psammatodes, proveniente de Icapuí, foi submetido a processo de fracionamento e purificação por diversas técnicas cromatográficas, obtendo-se quatro nucleosídeos (2-deoxiuridina, 2-deoxiinosina, timidina e 2-deoxiguanosina), três esteróides em mistura (colestanol, colestanona e estigmasterol) e três derivados do glicerol éter em mistura (2,3-propanodiol, 1- heptadeciloxi; álcool batílico e 2,3-propanodiol, 1-nonadeciloxi). O extrato metanólico de D. psammatodes, proveniente de Trairi, foi inicialmente particionado, originando as fases aquosa, hexânica, clorofórmica, butanólica e hidroalcoólica. A fase hexânica inibiu o ciclo celular de ovos de ouriço do mar e exibiu toxicidade em células tumorais. Ela foi fracionada por técnicas cromatográficas e obtiveram-se três ácidos graxos metilados em mistura (miristato de metila, palmitato de metila e estearato de metila), dois esteróides em mistura (colestanol e colestanona), dois ácidos graxos em mistura (ácido palmítico e ácido esteárico) e três derivados do glicerol éter em mistura (2,3-propanodiol, 1-heptadeciloxi; álcool batílico e 2,3- propanodiol, 1-nonadeciloxi). A fase clorofórmica também inibiu o ciclo celular de ovos de ouriço do mar e exibiu toxicidade em células tumorais. Ela foi fracionada por técnicas cromatográficas e obtiveram-se seis ácidos graxos em mistura (ácido láurico, ácido mirístico, ácido pentadecanóico, ácido palmítico, ácido margárico e ácido esteárico). A fase aquosa foi submetida ao processo de fracionamento e purificação por diversas técnicas cromatográficas, obtendo-se dois nucleosídeos (uridina e timidina) e um núcleo purínico (hipoxantina). A fase butanólica resultou no isolamento e identificação de dois nucleosídeos (2-deoxiguanosina e timidina). Amostras de Eudistoma vannamei foram coletadas em São Gonçalo do Amarante (CE). O extrato metanólico de E. vannamei foi particionado, originando as fases hexânica e hidroalcoólica. A fase hexânica inibiu o ciclo celular de ovos de ouriço do xi mar e exibiu toxicidade em células de linhagem B-16. Ela foi fracionada por técnicas cromatográficas e obtiveram-se cinco ácidos graxos metilados (miristato de metila, palmitato de metila, estearato de metila, palmitoleato de metila e oleato de metila), dois esteróides (colestanona e colesterol) e cinco ácidos graxos (ácido mirístico, ácido pentadecanóico, ácido palmítico, ácido margárico e ácido esteárico). A fase hidroalcoólica resultou no isolamento e identificação de dois nucleosídeos (guanosina e adenosina). As substâncias foram identificadas por métodos espectroscópicos e cromatográficos, comparando-se os valores obtidos com aqueles da literatura e padrões. Os nucleosídeos 2-deoxiuridina e 2-deoxiguanosina inibiram o ciclo celular de ovos de ouriço do mar em ambas fases examinadas. Os ácidos graxos metilados de D. psammatodes, o ácido palmítico junto com ácido esteárico e os derivados do glicerol éter inibiram o ciclo celular de ovos de ouriço do mar durante a primeira divisão. Os ácidos graxos metilados de D. psammatodes apresentaram maior toxicidade nas linhagens tumorais analisadas, sendo que a mistura de ácidos graxos metilados de E. vannamei também mostrou toxicidade em células tumorais leucêmicas. Ambas amostras de ácidos graxos metilados mostraram efeitos antiproliferativos e citotóxicos e estas atividades envolveram a inibição da síntese de DNA e indução de apoptose e necrose. / Samples of Didemnum psammatodes were collected in Icapui (Ceara State) and Trairi (Ceara State). The methanolic extract from D. psammatodes, acquired from Icapui, was submitted to fractionation and purification through several chromatographic techniques and were obtained four nucleosides (2?-deoxyuridine, 2- deoxyinosine, thyimidine, and 2?-deoxyguanosine), three steroids in mixture (cholestanol, cholestanone, and stigmasterol) and three glyceryl ethers in mixture (2,3-propanediol, 1-(heptadecyloxy), batyl alcohol, and 2,3-propanediol, 1- (nonadecyloxy)). The methanolic extract from D. psammatodes, acquired from Trairi, was initially partitionated, giving rise to aqueous, hexane, chloroform, and butanol phases. The hexane phase inhibited the sea urchin egg cell cycle and exhibited toxicity in tumor cell lines. It was fractionated by several chromatographic techniques and obtained three fatty acid methyl esters in mixture (methyl myristate, methyl palmitate, and methyl stearate), four steroids in mixture (cholestanol and cholestanone), two fatty acids in mixture (palmitic acid and stearic acid) and three glyceryl ethers in mixture (2,3-propanediol, 1-(heptadecyloxy), batyl alcohol, and 2,3- propanediol, 3-(nonadecyloxy)). The chloroform phase also inhibited the sea urchin egg cell cycle and exhibited toxicity in tumor cell lines. It was fractionated through several chromatographic techniques and obtained six fatty acids in mixture (lauric acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, and stearic acid). The aqueous phase was submitted to fractionation and purification by several chromatographic techniques and obtained two nucleosides (uridine and thymidine) and one purinic nucleus (hypoxanthine). The butanol phase resulted in the isolation and identification of two nucleosides (2?-deoxyguanosine and thymidine). Samples of Eudistoma vannamei were collected in São Gonçalo do Amarante (Ceara State). The methanolic extract from E. vannamei was partitionated, giving rise to hexane and hydroalcoholic phases. The hexane phase inhibited the sea urchin egg cell cycle and xiii exhibited toxicity in cell line B-16. It was fractionated by chromatographic techniques and obtained five fatty acid methyl esters in mixture (methyl myristate, methyl palmitate, methyl stearate, methyl palmitoleate, and methyl oleate), two steroids (cholestanol and cholesterol), and five fatty acids (myristic acid, pentadecanoic acid, palmitic acid, margaric acid, and stearic acid). The hydroalcoholic phase resulted in the isolation and identification of two nucleosides (guanosine and adenosine). The substances were identified by spectroscopic and chromatographic methods comparing the obtained values with those of the literature and standards. The nucleosides 2?-deoxyuridine and 2?-deoxyguanosine inhibited the sea urchin egg cell cycle in both stages. The fatty acid methyl esters from D. psammatodes, the palmitic acid plus stearic acid and the glyceryl ethers inhibited the sea urchin egg cell during first cleavage. The fatty acid methyl esters from D. psammatodes presented the highest toxicity in the cell lines tested and the mixture of fatty acid methyl esters from E. vannamei showed toxicity to leukemia cell lines too. Both samples of fatty acid methyl esters showed antiproliferative and cytotoxic effects and these activities involved the inhibition of DNA synthesis and induction of both necrosis and apoptosis.

This thesis describes the chemical investigations of several ascidian species collected from the Great Barrier Reef, Queensland, Australia. The thesis is divided into two separate components, Part A focuses on the isolation and structure elucidation of 11 previously undescribed ascidian metabolites. All structures were assigned using a combination of spectroscopic and/or chemical methods. Part B relates to the isolation and chemical conversion of a natural product to a combinatorial template. The natural product template was subsequently used in the generation of a solution-phase combinatorial chemistry library. A further two combinatorial libraries were generated from a synthesised model compound that was related to the natural product template. Part A. Investigation of Aplidium longithorax collected from the Swains Reefs resulted in the isolation of two new para-substituted cyclofarnesylated quinone derived compounds, longithorones J (30) and K (31). The former compound had its absolute stereochemistry determined by the advanced Mosher method. From an Aplidium longithorax collected from Heron Island, two new cyclofarnesylated hydroquinone compounds, longithorols C (46) and D (47) and a novel macrocyclic chromenol, longithorol E (48) were isolated. Longithorol C (46) had its absolute stereochemistry determined by the advanced Mosher method. Chemical investigation of the deep-purple colonial ascidian, Didemnum chartaceum collected from Swains Reefs led to the isolation of five new lamellarin alkaloids, which included the 20-sulfated derivatives of lamellarins B (94), C (95) and L (96), the 8-sulfated derivative of lamellarin G (97) and the non-sulfated compound, lamellarin Z (98). The known lamellarins A (63), B (80), C (64), E (65), G (67), and L (71) plus the triacetate derivatives of lamellarin D (82) and N (83) were also isolated. An aberration in the integration of signals in the 1H NMR spectra of the 20-sulfated derivatives (94-96) led to NMR relaxation studies. T1 values were calculated for all protons in the sulfated lamellarins (94-97) and their corresponding non-sulfated derivatives (80, 64, 71, 67). The protons ortho to the sulfate group in compounds (94-97) had T1 values up to five times larger than the corresponding protons in their non-sulfated derivatives (80, 64, 71, 67). A specimen of Eudistoma anaematum collected from Heron Island was shown to contain a new b-carboline alkaloid, eudistomin V (130), in addition to the two known metabolites, eudistomin H (105) and I (106). Part B. The known natural products, 1,3-diphenethylurea (29), 1,3-dimethylxanthine (30), 1,3-dimethylisoguanine (31) and the salts of tambjamine C (16), E (18) and F (19) were isolated from the ascidian, Sigillina signifera collected in Blue Lagoon, Lizard Island. Base hydrolysis on mixtures of the salts of tambjamine C (16), E (18) and F (19) resulted in the production of 4-methoxy-2,2-bipyrrole-5-carbaldehyde (26). This natural product template (26) was used in the generation of an enamine combinatorial chemistry library (98, 103-111) using solution-phase parallel synthesis. The biaryl compound, 4-(2-thienyl)-1H-pyrrole-2-carbaldehyde (59) was successfully synthesised using Suzuki-Miyaura coupling conditions and subsequently used as a template in the generation of an amine (67, 77, 80-87) and imine (78, 92-95) combinatorial library using solution-phase parallel synthesis.

No description available.

No description available.

No description available.