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Large individuals of the sea anemone <i>Actinia fragacea</i> were collected at approximately monthly intervals over a two year period. Their gonads were examined by light and electron microscopy, in order to follow the gametogenic process. The sexes are separate, and both show an annual cycle of activity. Oocytes arise in the gonad epithelia, but soon migrate into the mesogloea. During vitellogenesis, the oocytes accumulate compound yolk granuleso fibrillar and cortical granules, lipid droplets and glycogen. The surface of large oocytes bears tufts of large microvilli or cytospines. The oocytes reach some 150 pm in size. A group of specialized gonad epithelial cells projects through the mesogloea and contacts the oocyte surface, forming the trophonema, which is involved with nutrient transfer. The gonad epithelium can take up nutrients from the external medium, and the trophonema is particularly active in the uptake and incorporation of some small molecules. Not all fully grown oocytes are always spawned; some break down in an orderly fashion and are resorbed. Oogenesis was also examined, in less detallo in four other species of anemone. Spermatogenesis takes place in spherical testicular cysts, which are also associated with trophonemata. Spawning occurred in the laboratory on three occasions. Spawned eggs do not possess a vitelline coat, and do not undergo a cortical reaction. Gastrulae may take up numerous supernumary sperm.

Seagrass bed is a highly productivity ecosystem, it also provides habitats for animals and plays an important role in stabilizing the substrate. The sea anemone Phymanthus strandesi is very abundant in the seagrass bed of Thalassia hemprichii on Hsiao-Liuchiu Island. Structural Equation Modeling (SEM) was used to investigate the relationship between P. strandesi and some environmental factors, which affect the distribution of this species at Tuozaiping tidal flat (N 22¢X20"55' E 120¢X21"49'), Hsiao-Liuchiu Island. Light and temperature were also manipulated in the laboratory to test their effect on the hiding response of P. strandesi. The results of SEM show that the abundance of T. hemprichii showed very weak positive relation with P.strandesi. On the other hand, soil depth on the seagrass bed might be the main factor that affects the distribution of P. strandesi. In high a temperature situation (i.e. over 38¢XC), all the sea anemones in the experimental container hided into the sand. However, only some sea anemones hid when exposed to strong light (i.e. 5030 lum/ft²) after one and half hours.

Made available in DSpace on 2014-06-11T19:23:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-24Bitstream added on 2014-06-13T19:49:43Z : No. of bitstreams: 1 pigossi_ft_me_araiq.pdf: 1126356 bytes, checksum: 760162fd7a380d3e6dcbce0c956356a5 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A Stichodactyla helianthus é uma anêmona relativamente abundante nos mares de Cuba apresentando grande potencialidade como fonte de peptídeos biologicamente ativos. Dentre estes peptídeos, estão duas citolisinas: as esticolisinas I (St I) e II (St II). Essas duas toxinas possuem como principal característica a capacidade de formação de poros em eritrócitos, ou seja, alta atividade hemolítica (AH), no entanto a St II é mais hemolítica que a St I. Tendo em vista que as principais alterações que diferenciam estas citolisinas (St I e St II) estão na região amino-terminal (primeiros 30 resíduos), este trabalho teve como um dos objetivos sintetizar e comparar fragmentos amino-terminais destes polipeptídeos, visando entender a diferença de atividade hemolítica. Os resultados obtidos mostraram que os peptídeos St I 12-31 e St II 11-30 possuem a mesma atividade hemolítica. Esse dado mostra que a alteração de Glu por Gly e de Gln por Glu não afeta a atividade hemolítica dos mesmos. Já os peptídeos St I 1-31 e St II 1-30, respectivamente, mostraram diferenças em suas atividades hemolíticas, estas diferenças de atividade podem estar relacionadas à região dos resíduos de 1 a 10 da seqüência peptídica. Outro resultado interessante foi que o peptídeo St I 2-31 (sem o resíduo de serina N-terminal) apresentou AH intermediária entre os St I 1-31 e St II 1-30, mostrando que a adição da serina à St I é responsável por parte da perda da atividade desta citolisina. Outro objetivo deste trabalho foi avaliar a importância da polaridade da extremidade amino-terminal da esticolisina II. Para isto, fragmentos peptídicos contendo a região amino-terminal da St II, marcado com Trp na posição 2, foi sintetizado alterando-se a carga desta extremidade (acetilado, acrescido de Ser, Asp ou Lys) / Stichodactyla helianthus is a relatively abundant sea anemone found in the seas of Cuba, presenting a largely potent source of biologically active peptides. Among these peptides, are two citolysins: the sticholysins I (St I) and II (St II). These two toxins possess as main characteristic the capacity of forming pores in erythrocytes, in other words, high hemolytic activity (HA), however, the St II is more hemolytic than the St I. As far as we know that the main alterations that differentiate the proteins St I and St II are in the region amino-terminal (first 30 residues), this study has as one of the objectives the synthesizing and comparing of amino-terminal fragments of those polypeptides aiming to understand the difference of hemolytic activities. The results obtained had shown that the peptides St I 12-31 and St II 11-30 possess the same hemolytic activity. This data sample shows that the alteration of Glu for Gly and Gln for Glu does not affect the hemolytic degree of the same ones. Even then the peptides St I 1-31 and St II 1-30, respectively, had sample differences in its hemolytic activity, indicating that the different activities can be related within the region of 1 the 10 of the sequence. Another interesting result was that the peptides St I 2-31 (without the serine residue N-terminal) presented intermediary AH between St I 1-31 and St II 1-30, showing that the addition of the serine to St I is responsible for part of the losing activity in this citolysin. Another objective of this study is to evaluate the importance of polarity of the extremity amino-terminal of sticholysin II. To do this, the peptides containing the region amino-terminal of St II, marked with Trp in position 2, was synthesized changing the load of this extremity (acetylated, increased of Ser, Asp or Lys)

Anemonefish are one of the main groups that have been used over the last decade to empirically measure larval dispersal and connectivity in coral reef populations. A few species of anemones are integral to the life history of these fish, as well as other obligate symbionts, yet the biology and population structure of these anemones remains poorly understood. The aim of this study was to measure the genetic structure of these anemones within and between two reefs in order to assess their reproductive mode and dispersal potential. To do this, we sampled almost exhaustively two anemones species (Stichodactyla gigantea and Heteractis magnifica) at two small islands in Kimbe Bay (Papua New Guinea) separated by approximately 25 km. Both the host anemones and the anemonefish are heavily targeted for the aquarium trade, in addition to the populations being affected by bleaching pressures (Hill and Scott 2012; Hobbs et al. 2013; Saenz- Agudelo et al. 2011; Thomas et al. 2014), therefore understanding their biology is crucial for better management strategies. Panels of microsatellite markers were developed for each species using next generation sequencing tools. Clonality analyses confirm six pairs of identical genotypes for S. gigantea (n=350) and zero for H. magnifica (n=128), indicating presence/absence of asexual reproduction in this region. S. gigantea showed low structure between islands (FST= 0.003, p-value= 0.000), however, even if the majority of the individuals were unrelated (r~0), 81 families that shared 50% of their genetic material formed from two to four members were found. Out of these families, 45% were found with individuals only within Tuare Island, 11% only in Kimbe Island, and 44% were sharing individuals among islands. In comparison, H. magnifica showed no structure (FST= 0.002, p-value= 0.278), mean relatedness indicated the majority of individuals were unrelated, and 31 families were identified. Families again consisted from two to four members and were found within Kimbe Island 90% of the time, and shared between islands the remaining 10%. Results show the first genetic evidence of their reproductive characteristics, high levels of connectivity among islands and significant levels of genetic relatedness among individuals within islands.

Orientador: Eduardo Maffud Cilli / Banca: Antonio de Miranda / Banca: Hosana Maria Debonsi Navickiene / Resumo: A Stichodactyla helianthus é uma anêmona relativamente abundante nos mares de Cuba apresentando grande potencialidade como fonte de peptídeos biologicamente ativos. Dentre estes peptídeos, estão duas citolisinas: as esticolisinas I (St I) e II (St II). Essas duas toxinas possuem como principal característica a capacidade de formação de poros em eritrócitos, ou seja, alta atividade hemolítica (AH), no entanto a St II é mais hemolítica que a St I. Tendo em vista que as principais alterações que diferenciam estas citolisinas (St I e St II) estão na região amino-terminal (primeiros 30 resíduos), este trabalho teve como um dos objetivos sintetizar e comparar fragmentos amino-terminais destes polipeptídeos, visando entender a diferença de atividade hemolítica. Os resultados obtidos mostraram que os peptídeos St I 12-31 e St II 11-30 possuem a mesma atividade hemolítica. Esse dado mostra que a alteração de Glu por Gly e de Gln por Glu não afeta a atividade hemolítica dos mesmos. Já os peptídeos St I 1-31 e St II 1-30, respectivamente, mostraram diferenças em suas atividades hemolíticas, estas diferenças de atividade podem estar relacionadas à região dos resíduos de 1 a 10 da seqüência peptídica. Outro resultado interessante foi que o peptídeo St I 2-31 (sem o resíduo de serina N-terminal) apresentou AH intermediária entre os St I 1-31 e St II 1-30, mostrando que a adição da serina à St I é responsável por parte da perda da atividade desta citolisina. Outro objetivo deste trabalho foi avaliar a importância da polaridade da extremidade amino-terminal da esticolisina II. Para isto, fragmentos peptídicos contendo a região amino-terminal da St II, marcado com Trp na posição 2, foi sintetizado alterando-se a carga desta extremidade (acetilado, acrescido de Ser, Asp ou Lys) / Abstract: Stichodactyla helianthus is a relatively abundant sea anemone found in the seas of Cuba, presenting a largely potent source of biologically active peptides. Among these peptides, are two citolysins: the sticholysins I (St I) and II (St II). These two toxins possess as main characteristic the capacity of forming pores in erythrocytes, in other words, high hemolytic activity (HA), however, the St II is more hemolytic than the St I. As far as we know that the main alterations that differentiate the proteins St I and St II are in the region amino-terminal (first 30 residues), this study has as one of the objectives the synthesizing and comparing of amino-terminal fragments of those polypeptides aiming to understand the difference of hemolytic activities. The results obtained had shown that the peptides St I 12-31 and St II 11-30 possess the same hemolytic activity. This data sample shows that the alteration of Glu for Gly and Gln for Glu does not affect the hemolytic degree of the same ones. Even then the peptides St I 1-31 and St II 1-30, respectively, had sample differences in its hemolytic activity, indicating that the different activities can be related within the region of 1 the 10 of the sequence. Another interesting result was that the peptides St I 2-31 (without the serine residue N-terminal) presented intermediary AH between St I 1-31 and St II 1-30, showing that the addition of the serine to St I is responsible for part of the losing activity in this citolysin. Another objective of this study is to evaluate the importance of polarity of the extremity amino-terminal of sticholysin II. To do this, the peptides containing the region amino-terminal of St II, marked with Trp in position 2, was synthesized changing the load of this extremity (acetylated, increased of Ser, Asp or Lys) / Mestre

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2012. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-10-11T11:38:27Z No. of bitstreams: 1 Lais.pdf: 937026 bytes, checksum: 99723480330641cd5bc515f0c200b9f0 (MD5) / Approved for entry into archive by Sabrina Andrade (sabrinabeatriz@ibest.com.br) on 2013-10-17T17:16:57Z (GMT) No. of bitstreams: 1 Lais.pdf: 937026 bytes, checksum: 99723480330641cd5bc515f0c200b9f0 (MD5) / Made available in DSpace on 2013-10-17T17:16:57Z (GMT). No. of bitstreams: 1 Lais.pdf: 937026 bytes, checksum: 99723480330641cd5bc515f0c200b9f0 (MD5) Previous issue date: 2012 / Os organismos bentônicos intermareais enfrentam oscilações periódicas nos níveis de oxigênio na água associadas ao ciclo de marés. Durante o recuo da maré, eles ficam expostos ao ar e sujeitos a hipóxia, favorecendo uma redução nas espécies reativas de oxigênio (ERO) e nas defesas antioxidantes. Porém, na reoxigenação há um aumento acentuado na geração de ERO. Para minimizar os prejuízos desse processo, existem mecanismos antecipatórios, tal como o aumento das defesas antioxidantes durante a hipóxia. Por sua vez, o estresse causado por poluentes químicos, como o cobre, pode alterar o padrão destas respostas. Neste estudo foram avaliadas respostas de biomarcadores associados ao estresse oxidativo e metabolismo (capacidade antioxidante total contra radicais peroxil - ACAP, atividade da superóxido dismutase - SOD, concentração de glutationa reduzida - GSH, peroxidação lipídica - LPO e concentração de ATP) na anêmona Bunodosoma cangicum pré-exposta (96 h) ao cobre (6,1 ± 2.7 μg.L-1) e submetida a hipóxia (6 h a 0.5 mgO2.L-1) seguida da reoxigenação (6 h a 7.5 mg O2.L-1). Nas anêmonas controle não foram observadas variações na ACAP, GSH, LPO e ATP. Entretanto, a atividade da SOD aumentou durante a hipóxia. Nas anêmonas pré-expostas ao cobre, a ACAP foi reduzida na hipóxia e reoxigenação. A atividade da SOD não se alterou e a concentração de GSH aumentou no início do experimento, na hipóxia e na reoxigenação. A concentração de ATP diminuiu na reoxigenação, porém a LPO não se alterou em todas as condições experimentais. Estes resultados indicam a existência de mecanismos antecipatórios para prevenção dos efeitos negativos da reoxigenação em B. cangicum e que a exposição ao cobre em concentração ambientalmente relevante afeta negativamente estes mecanismos. / Intertidal benthic organisms are subjected to changes in oxygen availability during the tidal cycle. A hypoxic condition may occur during air exposure, thus favoring a decreased level of oxygen reactive species (ROS) and antioxidant defenses. However, during re-oxygenation a ROS overproduction may occur. Anticipatory mechanisms such as a buildup of antioxidant defenses under hypoxia could be present to avoid a possible oxidative damage occurring during these processes. In turn, chemical stress induced pollutants such as copper may affect the response of these mechanisms. In the present study, the response of biomarkers associated with oxidative stress and energy (total antioxidant capacity against peroxyl radicals - ACAP, superoxide dismutase activity - SOD, lipid peroxidation - LPO, reduced glutathione - GSH, and ATP concentration) were evaluated in the sea anemone Bunadosoma cangicum pre-exposed (96 h) to copper (6.1 ± 2.7 μg.L-1) and submitted to hypoxia (6 h at 5 mg O2.L-1) followed by re-oxygenation (6 h at 7.5 mg O2.L-1). In sea anemones kept under control conditions, ACAP, GSH concentration, LPO and ATP concentration did not change over the experimental time. However, SOD activity was increased under hypoxia. In sea anemones pre-exposed to copper, ACAP was reduced under hypoxia and re-oxygenation. GSH concentration was increased during hypoxia and reoxygenation, while ATP concentration was reduced during re-oxygenation. These findings indicate that B. cangicum shows anticipatory mechanisms to avoid the oxidative stress during re-oxygenation and that pre-exposure to an environmentally relevant concentration of copper affects these mechanisms.

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