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1.
A partial length cDNA coding for the putative PAH-inducible phenol-conjugating UDP-glucururonosyltransferases (UGT) isoform of plaice was used to isolate overlapping clones from a plaice genomic library. Sequence analysis revealed the presence of a complete gene spanning 4.1 kb for a plaice UGT which showed a strong conservation in exon structure, amino acid character and amino acid sequence with mammalian UGT1 family genes, although additional alternative upstream exon 1s were not identified in the present study. Southern blot analysis revealed a low copy number for the gene and some degree of structural polymorphism in gene structure between individuals. This was also reflected in the finding that there were significant variations between the nucleotide sequences of the plaice gene and the cDNA previously isolated from a different individual fish. Future studies will investigate the possibility that there may be phenotypic variations which could lead to alterations in susceptibility to pollutant toxicity. 相似文献
2.
The presence of multiple distinct UGT genes in fish was derived by analysis of DNA sequence data derived the zebrafish EST project, confirming indications from previous protein purification studies in another fish species, the plaice, for a diversity of isoforms in lower vertebrates. At least 10 different UGTs can be identified from nucleotide sequence data in zebrafish. Phylogenetic analysis of exon 1 sequences of the zebrafish, plaice and human UGTs indicates that six of these genes are related to the 1A, 1B and 2 families and that a further four genes were of more ancient lineage. Importantly data for the 3' sequences of the zebrafish clones, both from the database and our own sequences of the publicly available clones did not provide any evidence for elaboration of family 1A genes by alternative splicing in this lower vertebrate. 相似文献
3.
Baseline data for hepatic xenobiotic metabolizing biomarker enzyme activities were obtained for artificially reared tilapia Oreochromis niloticus, and were compared with those of the plaice (Pleuronectes platessa) and rainbow trout (Onchorynchus mykiss). Basal activities exhibited species variations with notably higher CYP1A and phenol UGT activities and lower GST activity in plaice than the freshwater species. Interspecies relationships between gene families determined by immunoblotting and substrate-activity profiles demonstrated the presence of homologous CYP1A and CYP3A enzymes in all three species, alpha class GSTs in plaice and trout, mu and pi class GSTs in trout and theta class GSTs in plaice and tilapia. CYP1A of tilapia was induced by 3-MC or PBO treatment, whilst CYP3A was induced by PCN treatment. 相似文献
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5.
Distribution and quality of plaice (Pleuronectes platessa) nursery grounds on the Swedish west coast
《Journal of Sea Research》2007,57(2-3):218-229
Plaice (Pleuronectes platessa) has spatially restricted nursery grounds located in shallow soft bottom areas, where the nursery areas only make up a small fraction of the species distribution range. The importance of different coastal areas for recruitment is expected to depend on the quality and size of the nursery grounds. This paper describes the geographical extension of plaice nursery grounds at a regional level along the Swedish west coast. Densities of juvenile plaice were used as the response variable of habitat quality and were compiled based on records from autumn sampling in the various regions. Different aspects of nursery ground quality were related to the density of 0-group plaice, to evaluate the contribution of different factors to the geographical pattern observed. Larval supply was found to be the most important component of nursery quality showing a close relationship with the density of juvenile plaice on a regional scale. The relative contribution of plaice recruits from Swedish nursery grounds to the Skagerrak/Kattegat stock was evaluated using historical data. Swedish nursery grounds were estimated to contribute 77% of the recruits to the adult stock in the area. 相似文献
6.
cDNA clones for glutathione S-transferases A (GST-A) and A1 (GST-A1) from plaice (Pleuronectes platessa) were expressed as N-terminally 6XHis tagged proteins in Escherichia coli and purified to homogeneity from Ni-NTA silica. GST-A was an efficient catalyst for conjugation of unsaturated alkenals derived from peroxidation of polyunsaturated fatty acids with the highest activity observed with trans-non-2-enal (8 micromol min(-1) mg(-1)). GST-A1 was a very efficient Se-independent glutathione peroxidase with an activity towards cumene hydroperoxide of 25 micromol min(-1) mg(-1). Although the enzymes exhibited moderately high activities towards the model substrate 1-chloro-2,4-dinitrobenzene (CDNB) they exhibited little or no activity towards other common prototypical xenobiotic substrates. Together with data for ontogeny, tissue distribution and inducibility of these enzymes, we contend that a primary function of these enzymes is protection from the harmful effects of lipid peroxidation products generated naturally or exacerbated by xenobiotic exposure. 相似文献
7.
In 1994, a directed fishing moratorium was declared for Grand Bank American plaice (Hippoglossoides platessoides) and yellowtail flounder (Limanda ferruginea) stocks because both stocks showed severe declines in abundance from heavy exploitation during the mid 1980s and early 1990s. Four years later, the fishery for yellowtail re-opened while the plaice stock has shown little recovery and the moratorium is still in effect. To assess the possible causes of the differences in recovery between species, we examined the spatial structure and environmental characteristics of the continental shelf nursery habitats of plaice and yellowtail, and their relationship to recruitment variability and overall population size. Depth plays a major influential role determining the spatial pattern and the abundance of juveniles of both species and in the case of plaice the spatial structure of the adult population also determines the amount of nursery area utilised by juveniles. Recruitment variability was higher in plaice than in yellowtail. We found year class synchrony in both species indicating that common environmental conditions and/or biological processes are affecting recruitment in a similar manner. Density-dependent regulation appears to be more severe in yellowtail and this should contribute to a more stable population when compared to plaice. These results are discussed in terms of resiliency of both stocks to over-exploitation. 相似文献
8.
The hypothesis that recruitment variation in flatfishes should be most variable at the northern edge of the species range, least near the centre of the range, and intermediate near the southern limit was tested using stock and recruitment data generated from sequential population analysis for several different flatfish stocks involving four species (plaice Pleuronectes platessa, sole Solea vulgaris from the eastern Atlantic, American plaice Hippoglossoides platessoides, and yellowtail flounder Limanda ferruginae from the western Atlantic). Several groundfish species have been found to conform to this so-called species range hypothesis with the suggestion that density-independent processes predominate at the edges of the distributional range and density-dependent processes dominate in the centre of the range. Our results were generally inconsistent with the hypothesis: the coefficient of variation (CV) of recruitment for plaice in the eastern Atlantic was independent of latitude, the CV of recruitment for sole exhibited a dome-shaped relationship with latitude with the highest CVs occurring at the mid-point of the range, and the CV of recruitment for the western Atlantic stocks exhibited a monotonic decrease with latitude. We extended our latitudinal analyses by assessing both the degree of dependency of recruitment on spawning stock biomass and the spatial and temporal scales of variability in recruitment and pre-recruit survival for the eastern Atlantic stocks. In general our analysis revealed no evidence of a strong stock and recruitment relationship for any of the stocks examined, and previously published analyses revealed no such patterns with latitude. Analysis of both de-trended recruitment and pre-recruit survival time series over the species ranges of sole and plaice revealed strong positive correlations among adjacent stocks and inverse correlations among stocks at the extremes of the range. Recruitment variation in the flatfish stocks examined appears to be dominated by density-independent factors, operating at a local scale, on the egg and larval stages. 相似文献
9.
《Journal of Sea Research》2004,51(3-4):191-197
As a preliminary investigation into the genetic structure of Irish Sea plaice we genotyped samples of juvenile plaice from six inshore areas within the Irish Sea across eight microsatellite loci and compared them with fish from two sites from the Dutch Wadden Sea (North Sea stocks). Genetic variability in all samples was generally low for that typically observed at microsatellite loci. The number of alleles per locus varied between two and nine (average 5.5) and the observed heterozygosity ranged from 0.080 up to a maximum of 0.909 (average 0.382). Few significant heterozygote deficits were observed, even when the data set was pooled. The majority (98%) of genetic variation present was within, rather than between, populations. None of the pairwise comparisons of population differentiation (FST) were significant (P>0.05) and a Bayesian analysis of population structure provided no evidence for a partitioning of the samples. Since juveniles arriving at nursery grounds in the Irish Sea are not distinct, it is likely that adult plaice form a single stock (perhaps with some weak differentiation). However, if plaice eggs and larvae do not disperse as predicted by a particle tracking model, then it is possible that the juveniles represent a mixture of several distinct stocks. Further work is therefore required to determine whether the phenotypic variation observed between female plaice from the eastern and western Irish Sea is the product of reproductive isolation or of the environment. 相似文献
10.
《Journal of Sea Research》2004,51(3-4):313-328
Fishing effort has strongly increased in the North Sea since the mid-19th century, causing a substantial reduction in the population size of exploited fish stocks. As fisheries research has developed simultaneously with the industrialisation of the fisheries, our knowledge of population dynamics at low levels of exploitations is limited. Otoliths retrieved from archaeological excavations offer a unique opportunity to study growth rates in the past. This study compares historical and present-day growth rates for four commercially important demersal fish species. A total of 2532 modern otoliths (AD 1984–1999) and 1286 historical otoliths (AD 1200–1925) obtained from archaeological excavations in Belgium and Scotland were analysed. Comparison of the growth patterns between eras revealed a major increase in growth rate of haddock, whereas growth changes were not observed in saithe and only in the smaller size classes of plaice and cod. Comparison of our results with literature data indicates that the observed growth rate changes in plaice and cod occurred within the 20th century. Apparently the onset of industrialised fisheries has not greatly affected the growth of plaice, cod and saithe populations in the North Sea. This result contradicts the expectation of density-dependent limitation of growth during the era of pre-industrialised fishing, but is in agreement with the concentration hypothesis of Beverton (Neth. J. Sea Res. 34 (1995) 1) stating that species which concentrate spatially into nursery grounds during their early life-history may ‘saturate’ the carrying capacity of the juvenile habitat even though the adult part of the population is not limited by the adult habitat. 相似文献
11.
cDNA's coding for cytochrome P4501A1 (CYP1A1), phenol UDP-glucuronosyltransferase (UDPGT) and glutathione S-transferase (GST-A) were cloned and sequenced from an expression library prepared from the liver of a 3-methylcholanthrene (3-MC) induced plaice. Plaice CYP1A1 and Phenol UDPGT display a high degree of structural conservation with homologous mammalian isoforms and their mRNAs were shown to be highly induced in liver after 3-MC treatment of fish. Expression of plaice GST-A, which displays closer homology to GSTs from plants and invertebrates than those of mammals, is repressed after 3-MC treatment. 相似文献
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13.
S. Calmant K. Cheng G. Jan C. Kuo C. Shum Y. Yi V. Ballu M. -N. Bouin 《Marine Geodesy》2004,27(3):597-613
A bottom pressure gauge (BPG) was installed in proximity (3.7 km at closest approach) of Jason-1 and formerly TOPEX/Poseidon (T/P) ground track No. 238 at the Wusi site, located ∼ 10 km offshore off the west coast of Santo Island, Vanuatu, Southwest (SW) Pacific. Sea level variations are inferred from the bottom pressure, seawater temperature, and salinity, corrected for the measured surface atmospheric pressure. The expansion of the water column (steric increase in sea surface height, SSH) due to temperature and salinity changes is approximated by the equation of state. We compare time series of SSH derived from T/P Side B altimeter Geophysical Data Records (GDR) and Jason-1 Interim Geophysical Data Records (IGDR), with the gauge-inferred sea level variations. Since altimeter SSH is a geocentric measurement, whereas the gauge-inferred observation is a relative sea level measurement, SSH comparison is conducted with the means of both series removed in this study. In addition, high-rate (1-Hz) bottom pressure implied wave heights (H1/3) are compared with the significant wave height (SWH) measured by Jason-1. Noticeable discrepancy is found in this comparison for high waves, however the differences do not contribute significantly to the difference in sea level variations observed between the altimeter and the pressure gauge. In situ atmospheric pressure measurements are also used to verify the inverse barometer (IB) and the dry troposphere corrections (DTC) used in the Jason IGDR. We observe a bias between the IGDR corrections and those derived from the local sensors. Standard deviations of the sea level differences between T/P and BPG is 52 mm and is 48 mm between Jason and BPG, indicating that both altimeters have similar performance at the Wusi site and that it is feasible to conduct long-term monitoring of altimetry at such a site. 相似文献
14.
采用特征量和线性拟合的方法,对1976～2003年8月的B1断面温盐调查资料进行分析.结果表明:夏季渤海暖水深入沿岸两端及渤海中部,深水处具有南北2个冷水区,形成冷、暖水体并存的分布特征.渤海夏季温度场结构分布是多种海洋物理环境要素的综合影响所致,太阳辐射和地形是基本原因之一,北黄海冷水侵入是冷暖水区维持的重要原因.冷水区多年温度有正变化率,温度变化正距平的信号来自大气气候变暖;而渤海中部高温水体则具有负变化率,温度变化负距平的信号来自北黄海次表层温度的变化,可能与北黄海冷水侵入渤海有关.夏季近岸盐度低,底层盐度高.盐度多年变化以正变率为主,造成岸边盐度升值明显的主要原因是河流入海淡水量的减少和工业污染. 相似文献
15.
《Marine Policy》2017
By 2019, the Common Fisheries Policy will prohibit discarding in all European fisheries of any pelagic, demersal or shellfish species for which removals are managed by TACs and quotas or minimum sizes. However, the regulation allows for exemptions from the prohibition for species for which scientific evidence demonstrates high survival rates associated with discarding. Producing reliable evidence of high survival typically requires long and costly studies involving tagging or captivity. This paper proposes to use the capacity to resist air exposure, a key stressor for discarded animals, as a proxy for survival that can be used to prioritize candidate species for more in-depth discard survival studies. The time required to induce mortality (TM) in air-exposed fish was estimated for ten discarded species under commercial fishing conditions for two artisanal French otter trawlers in the Bay of Biscay and in the English Channel. European seabass, plaice, sole and skates had extended TM values on average, suggesting that these species are good candidates. The three species observed in both regions (plaice, sole and skates) had larger TM values in the English Channel experiment compared to the Bay of Biscay experiment. Among the four measured external conditions that could influence TM (air temperature, fish length, tow depth and tow duration), the air temperature was the most important and the factor that most distinguished the two experiments. 相似文献
16.
C A Godard M J Leaver M R Said R L Dickerson S George J J Stegeman 《Marine environmental research》2000,50(1-5):7-10
The cytochromes P450 (CYP) constitute a multigene family of enzymes playing a critical role in the oxidation of many endogenous and xenobiotic substrates. The CYP1 family is of particular interest in environmental toxicology because its members are dominant in the metabolism of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and aryl amines. Three members of the CYP1 family, CYP1A1, CYP1A2, and CYP1B1, have been identified in mammals. We report here on the identification and cloning of cytochrome P4501B-like sequences from two teleost fish species and a marine mammal. Sequences clustering with CYP1B1 in phylogenetic analysis were obtained from liver cDNA of scup (Stenotomus chrysops), genomic DNA of plaice (Pleuronectes platessa), and liver cDNA of striped dolphin (Stenella coeruleoalba). 相似文献
17.
Julian Augley Mark Huxham Teresa F. Fernandes Alastair R. Lyndon 《Journal of Sea Research》2008,60(4):292-296
Previous population estimates of the 0+ plaice (Pleuronectes platessa L.) in the Firth of Forth, east central Scotland, did not take account of the Forth estuary west of the Forth bridges. Previous work found plaice in the estuary grew as fast as, or faster than, the outer firth plaice. It was hypothesised that salinity may affect growth rates of early 0+ plaice. This hypothesis was tested in a laboratory experiment, by exposing juvenile plaice to three different, but naturally — experienced by the juveniles, salinities; 25, 30 and 35. Plaice fed a minimum ration did not grow in length. Mean weight decreased at all three salinities, however, the lowest weight loss was found at the lowest salinity (25) and the highest weight loss was found at the highest salinity (35). The minimum feeding ration was halted and plaice were then fed ad libitum. Consumption rates were not significantly different during the ad libitum feeding, while significant differences in mean weight change were found between the highest and lowest salinities. 相似文献
18.
Liu Xiaolin Chang Yaqing Xiang Jianhai Li Fuhu Liu Xianjie Brovkina Elena Pavlovna 《海洋学报(英文版)》2003,22(2):255-263
Abstract-Based on the research of juvenile (2, 3, 4 months) growth and survival of three popu-lations of two different geographic areas in Chlamys farreri from Russian and China and their F_1 hybridsderived from Chinese cultural population (CC)×Russian population (RW), Chinese wild popu-lation (CW)×Russian population (RW), Russian population (RW)×Chinese wild popula-tion (CW), the study of the medium-term (6, 8, 10, 12 months) growth and development ofChlamys farreri was carried out. The four determined results indicated that there existed different ex-tent heterosis (3%～52%) for the growth in three types of F_1 hybrids, and the offspring derived fromCC×R had a stronger heterosis among the crosses at the medium-term; the uptrend among traitsare wet weight>shell width>shell length>shell height, Chinese cultural population could be recog-nized as excellent parent, and seasonal variations influence very much on the daily increment and growthrate of each trait of Chlamys farreri and it is only able to 相似文献
19.
本文以产沉(粘)性卵的鲱(Clupea harengus L.)和浮性卵的鲽(Pleuronectes platessa L.)为代表,对这两类海洋鱼类在卵和卵黄囊期仔鱼发育阶段水分、钠、钾、脂肪和蛋白质含量变化作了比较研究。实验于1987年春在苏格兰完成。结果发现:1)鲱的含水量在三个阶段有明显增长,受精时从75％—85％,卵发育期从85％—87％,孵化后从85％—90％;通过这一成功变化,最终使仔鱼获得浮性,上升并进入浮游生物水层摄食;鲽卵含水量在这三个阶段均保持在90％—92％,并一直保持相应的浮性,至摄食期。2)两种初孵仔鱼含水量的差别,主要由卵黄囊含水量不同引起,而身体其它部分含水量没有显著种的差别。3)鲱在钠、钾含量上的增长和波动,大致同这三个阶段湿重和含水量的增长和波动一致。4)脂肪和蛋白质对卵和仔鱼的浮性几乎不起作用;两种鱼在卵和卵黄囊期发育阶段,脂肪和蛋白质含量均呈线性下降。 相似文献
20.
对菲律宾海北部E-2岩心柱(29.62°N、131.14°E,水深3 877m)进行了浮游有孔虫δ18 O分析、AMS14 C测年以及U3k7表层海水温度(U3k7-SST)的测试。结果表明,E-2岩心记录了约19cal.kaBP以来U3k7-SST变化过程,其末次冰消期整体变化过程与北大西洋高纬地区相似,记录了Heinrich 1(H1)、Blling/Allerd(B/A)和Younger Dryas(YD)等快速气候事件,同时也识别出发生于19.4～19.2和18.5～18.0cal.kaBP的2次变冷事件,说明了研究区与北大西洋气候存在遥相关;在B/A和YD阶段中发现的百年尺度气候波动及变化过程,可能反映了热带过程对研究区域的影响;E-2岩心柱末次冰消期变暖存在阶段性,其变暖时间开始于19.4cal.kaBP,而大幅升温阶段则从15.3cal.kaBP开始。 相似文献