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Frank Melzner - One of the best experts on this subject based on the ideXlab platform.
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co2 induced seawater acidification impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO2 concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO2. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO2 41Pa e.g. 399μatm) and CO2 acidified seawater with pH of 7.7 (pCO2 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO2 treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO2 effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na+/K+-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
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co induced seawater acidification impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO₂ concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO₂. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO₂ 41Pa e.g. 399μatm) and CO₂ acidified seawater with pH of 7.7 (pCO₂ 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO₂ treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO₂ effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na⁺/K⁺-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
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co 2 induced seawater acidi cation impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO₂ concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO₂. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO₂ 41Pa e.g. 399μatm) and CO₂ acidified seawater with pH of 7.7 (pCO₂ 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO₂ treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO₂ effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na⁺/K⁺-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
Darlan De Jesus De Brito Simith - One of the best experts on this subject based on the ideXlab platform.
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salinity tolerance of northern brazilian mangrove crab Larvae ucides cordatus ocypodidae necessity for larval export
Estuarine Coastal and Shelf Science, 2006Co-Authors: Karen Diele, Darlan De Jesus De Brito SimithAbstract:The life cycle of the semiterrestrial mangrove crab Ucides cordatus includes pelagic Larvae that are released into estuarine waters during the wet season and who may thus encounter potentially stressful low and variable salinity conditions. The effect of salinity on the survival of the zoea Larvae, the number of zoeal stages and the duration of development from hatching to megalopa was experimentally studied by rearing Larvae from the Caete estuary, Northern Brazil, in seven salinity treatments (0, 5, 10, 15, 20, 25, and 30). For a better interpretation of the laboratory results, estuarine salinities were measured over five consecutive years during the species' reproductive season. The survival of the zoea Larvae varied significantly with salinity, while the number of stages and the duration of their development remained constant. Development to megalopa took 20.77 ± 1.57 days and comprised five zoeal stages with ZI and ZII being euryhaline and later stages stenohaline. The newly hatched Larvae stayed alive for up to 6 days in freshwater (average 4.32 ± 0.82 days), but did not moult to the second zoeal stage. ZII Larvae first occurred from salinity 5 onwards and later zoeal stages at all tested salinities ≥10. However, the Larvae only survived to megalopa at salinities ≥15, with highest numbers at salinity 30 (72%) and lowest at 15 (16%). Lethal salinities ≤10 occurred frequently in the estuary during the reproductive season. This suggests a need for larval export to offshore and thus more saline waters to allow for significant larval survival and maintenance of viable populations of this commercially important species. A regional rather than local approach for management is suggested due to the likelihood of long distance larval dispersal by offshore currents.
Meike Stumpp - One of the best experts on this subject based on the ideXlab platform.
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co2 induced seawater acidification impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO2 concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO2. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO2 41Pa e.g. 399μatm) and CO2 acidified seawater with pH of 7.7 (pCO2 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO2 treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO2 effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na+/K+-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
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co induced seawater acidification impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO₂ concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO₂. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO₂ 41Pa e.g. 399μatm) and CO₂ acidified seawater with pH of 7.7 (pCO₂ 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO₂ treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO₂ effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na⁺/K⁺-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
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co 2 induced seawater acidi cation impacts sea urchin larval development ii gene expression patterns in pluteus Larvae
Comparative Biochemistry and Physiology, 2011Co-Authors: Meike Stumpp, Sam Dupont, M C Thorndyke, Frank MelznerAbstract:Extensive use of fossil fuels is leading to increasing CO₂ concentrations in the atmosphere and causes changes in the carbonate chemistry of the oceans which represents a major sink for anthropogenic CO₂. As a result, the oceans' surface pH is expected to decrease by ca. 0.4 units by the year 2100, a major change with potentially negative consequences for some marine species. Because of their carbonate skeleton, sea urchins and their larval stages are regarded as likely to be one of the more sensitive taxa. In order to investigate sensitivity of pre-feeding (2days post-fertilization) and feeding (4 and 7days post-fertilization) pluteus Larvae, we raised Strongylocentrotus purpuratus embryos in control (pH 8.1 and pCO₂ 41Pa e.g. 399μatm) and CO₂ acidified seawater with pH of 7.7 (pCO₂ 134Pa e.g. 1318μatm) and investigated growth, calcification and survival. At three time points (day 2, day 4 and day 7 post-fertilization), we measured the expression of 26 representative genes important for metabolism, calcification and ion regulation using RT-qPCR. After one week of development, we observed a significant difference in growth. Maximum differences in size were detected at day 4 (ca. 10% reduction in body length). A comparison of gene expression patterns using PCA and ANOSIM clearly distinguished between the different age groups (two-way ANOSIM: Global R=1) while acidification effects were less pronounced (Global R=0.518). Significant differences in gene expression patterns (ANOSIM R=0.938, SIMPER: 4.3% difference) were also detected at day 4 leading to the hypothesis that differences between CO₂ treatments could reflect patterns of expression seen in control experiments of a younger larva and thus a developmental artifact rather than a direct CO₂ effect. We found an up regulation of metabolic genes (between 10%and 20% in ATP-synthase, citrate synthase, pyruvate kinase and thiolase at day 4) and down regulation of calcification related genes (between 23% and 36% in msp130, SM30B, and SM50 at day 4). Ion regulation was mainly impacted by up regulation of Na⁺/K⁺-ATPase at day 4 (15%) and down regulation of NHE3 at day 4 (45%). We conclude that in studies in which a stressor induces an alteration in the speed of development, it is crucial to employ experimental designs with a high time resolution in order to correct for developmental artifacts. This helps prevent misinterpretation of stressor effects on organism physiology.
Karen Diele - One of the best experts on this subject based on the ideXlab platform.
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salinity tolerance of northern brazilian mangrove crab Larvae ucides cordatus ocypodidae necessity for larval export
Estuarine Coastal and Shelf Science, 2006Co-Authors: Karen Diele, Darlan De Jesus De Brito SimithAbstract:The life cycle of the semiterrestrial mangrove crab Ucides cordatus includes pelagic Larvae that are released into estuarine waters during the wet season and who may thus encounter potentially stressful low and variable salinity conditions. The effect of salinity on the survival of the zoea Larvae, the number of zoeal stages and the duration of development from hatching to megalopa was experimentally studied by rearing Larvae from the Caete estuary, Northern Brazil, in seven salinity treatments (0, 5, 10, 15, 20, 25, and 30). For a better interpretation of the laboratory results, estuarine salinities were measured over five consecutive years during the species' reproductive season. The survival of the zoea Larvae varied significantly with salinity, while the number of stages and the duration of their development remained constant. Development to megalopa took 20.77 ± 1.57 days and comprised five zoeal stages with ZI and ZII being euryhaline and later stages stenohaline. The newly hatched Larvae stayed alive for up to 6 days in freshwater (average 4.32 ± 0.82 days), but did not moult to the second zoeal stage. ZII Larvae first occurred from salinity 5 onwards and later zoeal stages at all tested salinities ≥10. However, the Larvae only survived to megalopa at salinities ≥15, with highest numbers at salinity 30 (72%) and lowest at 15 (16%). Lethal salinities ≤10 occurred frequently in the estuary during the reproductive season. This suggests a need for larval export to offshore and thus more saline waters to allow for significant larval survival and maintenance of viable populations of this commercially important species. A regional rather than local approach for management is suggested due to the likelihood of long distance larval dispersal by offshore currents.
D. Vaïtilingon - One of the best experts on this subject based on the ideXlab platform.
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Maternal provisioning for Larvae and larval provisioning for juveniles in the toxopneustid sea urchin Tripneustes gratilla
Marine Biology, 2008Co-Authors: M. Byrne, T. A. A. Prowse, M. A. Sewell, S. Dworjanyn, J. E. Williamson, D. VaïtilingonAbstract:Lipid and protein biochemistry of eggs (84 μm in diameter), embryos and early Larvae of the tropical echinoid Tripneustes gratilla (Linnaeus 1758) were quantified to determine how maternal provisions are used to fuel development of the echinopluteus. The eggs contained a mean of 30.82 ng lipid and 87.32 ng protein. Energetic lipids were the major lipid component (55.52% of total lipid) with the major class being triglyceride (TG: mean 15.9 ng, 51.58% of total). Structural lipid was dominated by phospholipid (PL: mean 11.18 ng, 36.26% of total). Early embryogenesis was not a major drain on egg energetic lipid and protein. Development of the functional feeding larva used ca. 50% of initial egg energetic lipid and most of this was TG. Maternal TG was still present in the 8-day echinoplutei and it was estimated that this energetic lipid would be depleted in unfed Larvae by day 10. There was no change in PL. In a separate experiment lipid biochemistry of rudiment stage Larvae and early developing juveniles were quantified to determine how lipids are used during metamorphosis. Fed Larvae accumulated lipid (mean 275.49 ng) with TG and PL being the major energetic and structural lipids, respectively. Larval lipid stores were not appreciably depleted by metamorphosis and so were available for the early benthic stage juvenile. Juveniles started their benthic existence with 314 ng total lipid (TG: mean 46.84 ng, 14.9% of total, PL: mean 137.51 ng, 43.67% of total). Nile Red histochemistry and histology showed that the stomach serves as a nutrient storage organ and, that lipid stores accrued by Larvae sustain developing juveniles for up to 4 days post settlement. Triglyceride supported both non-feeding stages of development and the prefeeding larval and perimetamorphic benthic stage. In this first study of lipid stores in settlement stage echinoderm Larvae, we show that T. gratilla Larvae sequester the same major energetic lipid (TG) to support the early juvenile that the female parent provided them to fuel early development.
