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RNA helicases of the DEAD-box and related families are involved in various cellular processes including DNA replication,DNA repair,and RNA processing.However,the function of DEAD-box proteins in aquaculture species is poorly understood at molecular level.We obtained the full-length cDNA sequences of two genes encoding helicase-related proteins,Fc-vasa and Fc-PL10a,from the testes of Chinese shrimp,Fenneropenaeus chinensis.The two predicted amino acid sequences contain all the conserved motifs characterized ... 相似文献
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<正>In the original article, the name of the fourth author is incorrect. The correct one is Kyoung Ho Kang, in which "Kang" is the family name. The publishing companies apologize to the author. 相似文献
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Saccharina japonica is a common macroalga in sublittoral communities of cold seawater environments,and consequently may have highly effi cient ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)activity for carbon assimilation.In our study,we cloned the full-length Rubisco gene from S.japonica(SJ-rbc).It contained an open reading frame for a large subunit gene(SJ-rbcL)of 1 467 bp,a small subunit gene(SJ-rbcS)of 420 bp,and a SJ-rbcL /S intergenic spacer of 269 bp.The deduced peptides of SJ-rbcL and SJ-rbcS were 488 and 139 amino acids with theoretical molecular weights and isoelectric points of 53.97 kDa,5.81 and 15.84 kDa,4.71,respectively.After induction with 1 mmol/L isopropyl-β-Dthiogalactopyranoside for 5 h and purifi cation by Ni 2+ affi nity chromatography,electrophoresis and western blot detection demonstrated successful expression of the 55 kDa SJ-rbcL protein.Real-time quantitative PCR showed that the mRNA levels of SJ-rbcL in gametophytes increased when transferred into normal growth conditions and exhibited diurnal variations: increased expression during the day but suppressed expression at night.This observation implied that Rubisco played a role in normal gametophytic growth and development.In juvenile sporophytes,mRNA levels of SJ-rbcL,carbonic anhydrase,Calvin-BensonBassham cycle-related enzyme,and chloroplast light-harvesting protein were remarkably increased under continuous light irradiance.Similarly,expression of these genes was up-regulated under blue light irradiance at 350 μmol/(m 2·s).Our results indicate that long-term white light and short-term blue light irradiance enhances juvenile sporophytic growth by synergistic effects of various photosynthetic elements. 相似文献
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《中国海洋湖沼学报》2017,(4)
We evaluated the effects of lithium on the survival,growth,and reproduction of D.tibetana in the laboratory.The safe concentration value was 69.3 mg/L.The time to first brood was significant lower for individuals reared in 5 and 10 mg/L(24.4 and 24.0 d,respectively) compared with individuals reared in20,40,or 60 mg/L.Females reared in 5 mg/L lithium produced a mean of 16.5 neonates/brood and had the highest number of broods(3.0±1.95).The rate of egg production(a),the intrinsic rate of increase(r_m),net reproduction rate(R_0),and finite rate of increase(λ) were highest for D.tibetana reared at 5 and 10 mg/L lithium,and the duration of development was shorter than for the remaining groups.The results indicated that rearing in 5-10 mg/L lithium can accelerate the growth and reproduction of D.tibetana. 相似文献
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Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value,particularly in the aquaculture sector in Malaysia.This study was conducted to determine the feeding and food items of L.canarium at dif ferent ontogenetic stages(juveniles,sub-adults and adults)from Merambong shoals,Malaysia.Field observations on feeding activity were conducted,followed by detailed laboratory analysis on the stomach content.Five-minutes observations on randomly selected individuals were conducted at the fi eld sampling site and their feeding activities were recorded with reference to age stage.Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10%formalin before being transported to the laboratory for stomach content analyses.Field observations showed that L.canarium mainly grazed on epiphytes occurring on seagrass(46.67%),followed by sediment surface(40%)and epiphytes occurring on macroalgae(13.33%).Stomach content analyses showed a signifi cant dif ference(P0.05)in gastro-somatic index(Gasi)between the juveniles(0.39±0.05),sub-adults(0.68±0.09)and adults(0.70±0.05)(P0.05).Food items found in the conch stomach include diatoms,detritus,foraminifera,seagrass and macroalgae fragments,sand particles and shell fragments.The Index of Relative Importance(%IRI)indicates three main types of food dominated the three ontogenetic stages namely diatoms,sand particles and detritus.However,no signifi cant diff erence(P0.05)was detected between the three main food items(diatoms,sand particles and detritus)among the ontogenetic stages.Therefore,feeding activity revealed the role of the dog conch in the marine food network.While,classifi cation of the types of food consumed by L.canarium through stomach content analysis determines the particular position of the gastropod in the food chain.Further studies are needed to provide a better insight between trophic relationships of L.canarium with marine ecosystem. 相似文献
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The presence of Biecheleria cincta (=Woloszynskia cincta) in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle (EAV) were visible in the epicone, and both the hypocone and the cingulum had three series of vesicles each. Thin sections revealed that B. cincta possesses stalked pyrenoids and an unusual eyespot consisting of a stack of cisternae with brick-like materials (type E), thus supporting its transfer from Woloszynskia to Biecheleria. Spiny cysts formed spontaneously in culture, with an encystment rate of around 20%. Both large subunit ribosomal DNA (LSU rDNA) and internal transcribed spacer region (ITS) sequences in 12 strains from the Chinese coasts were determined. Phylogenetic analyses based on LSU rDNA and ITS sequences using Bayesian inference and maximum likelihood revealed two distinct ribotypes (referred to as ribotype A and B) in B. cincta. ITS region pairwise distances within B. cincta ranged from 0.024 to 0.072, suggesting the existence of a complex of cryptic species. 相似文献
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Journal of Oceanology and Limnology - The live-bearing genus Sebastes is renowned for its outstanding species richness and color diversity, and its speciation has been a point of interest. This... 相似文献
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Data on the distribution of dissolved inorganic carbon (DIC) were obtained from two cruises in the North Yellow Sea (NYS)
and off the Qingdao Coast (QC) in October, 2007. Carbonate parameters were calculated. The concentrations of DIC are from
1.896–2.229 mmolL−1 in the NYS and from 1.939–2.032 mmolL−1 off the QC. In the southwest of the NYS, DIC in the upper layers decreases from the north of the SP (Shandong Peninsula)
shelf to the center of the NYS; whereas in the lower layers DIC increases from the north of the SP shelf to the center of
the NYS and South Yellow Sea. In the northeast of the NYS, DIC in all layers increases from the YR (Yalu River) estuary to
the centre of the NYS. The distribution of DIC in NYS can be used as an indicator of Yellow Sea Cold Water Mass (YSCWM). Air-sea
CO2 fluxes were calculated using three models and the results suggest that both the NYS and the QC waters are potential sources
of atmospheric CO2 in October. 相似文献
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The use of LIDAR-derived shaded relief maps led to the identification of all potential landslide areas in a hilly region in Northern Bavaria (1590 km2), Germany. Every possible structure was investigated by field investigation which resulted in a detailed database of 1002 landslides within the study area. The analysis of geological, lithological, topographical and morphological properties (spatial ratio, lithological and geological setting, length/width distribution, material properties and slope angle) revealed characteristic appearances of the landslides and possible relationships between different aspects. Strong relations between the lithological setting, spatial ratio of the mapped landslides and distribution of slope angle could be observed. This study shows the value of high-resolution shaded relief maps for detecting and mapping landslides in a large area with comparatively little work and time in comparison to the traditional approach to mapping. It reveals that many landslides were not known before. Landslides are much more common in Northern Bavaria and have a higher influence on the denudation rate of the Franconian Alb than expected before. 相似文献
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Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate (SGR) of 10.47 at 25℃/40 μmol m^-2s^-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative cells could still divide actively in the algal tissues. 相似文献
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《世界地质(英文版)》2019,22(4)
The Volgian-Valanginian succession of shallow-water deposits from the Olenek section(Anabar-Lena region, Arctic Siberia) has been studied by sedimentological and palaeontological methods. High-resolution biostratigraphy of studied interval is based on the ammonites, foraminifers, marine and terrestrial palynomorphs. Foraminiferal and palynological zones have important regional implications providing well-constrained biostratigraphy of the Anabar-Lena region. Sedimentological studies together with ecological analysis of the associations of microbenthos, microphytoplankton and terrestrial palynomorphs allow the palaeoenvironmental reconstructions for the marginal area of the Anabar-Lena palaeosea and coastal land areas. 相似文献
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The morphological and molecular detection for the presence of toxic Cylindrospermopsis(Nostocales,Cyanobacteria) in Beijing city,China 总被引:1,自引:0,他引:1
Cylindrospermopsis raciborskii and its highly similar relatives R aphidiopsis species have been recognized as globally invasive and expansive filamentous cyanobacteria causing water blooms. Reports on C. raciborskii/Raphidiopsis species and their harmful metabolites such as hepatotoxic cylindrospermopsins(CYNs) in Chinese waters have been increasing, but mostly restricted to the southern regions of China. To further explore the existence and distribution of C. raciborskii in China, six water samples from Beijing city were morphologically and molecularly examined. Five samples of the six were shown to have C ylindrospermopsis filaments with straight and spiral morphotypes. PCR detection targeting on Cylindrospermopsis/Raphidiopsis specific 16 S r RNA gene region also showed the positive amplification, and such amplifications were confirmed by sequencing and phylogenetic analysis. As well, three of the five Cylindrospermopsis containing samples were shown to have c yr J — a gene of CYN synthesis gene cluster. The results represented the presence of toxic C ylindrospermopsis at the most northern line in China so far, indicating rapid expansion of this harmful invasive cyanobacterium. It is strongly suggested that the monitoring on C. raciborskii/R aphidiopsis species and their production of cylindrospermopsin should be emphasized in Beijing and even more northern parts of China. 相似文献
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Three kinds of tundra plant samples including Dicranum angnstum(a type of boreal bryophyte) , PuccineUia phryganodes (a type of fringy p/ant),Salix polaris (a type of vascular plant) and surface soil were samples in 200 at Ny-Alesund of the Arctic.The levels of eight heavy metal elements (Hg, Pb, Cd, Cu, Zn, Ni, Fe and Mn) and three metal-like dements (As, Se, Sr) in the plant and soil samples of the areas within previous coal mining activities are significantly higher than those of other areas.The relative accumulation of these elements in these tundra plant samples is consistent with the one in the soft samples, especially in the areas affected by previous coal-mining activities.Thus, the pollution is apparently from local coal mining activity.Dicranum angustum has the highest concentrations among those elements, and it can be a good bio-indicator for heavy metal pollution in Ny(A)lesund.Though Ny(A)lesund is less polluted by heavy metal than nearby Northern European human living areas, but much more than the tundras of the Alaska, Greenland and the Antarctic. 相似文献
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《中国海洋湖沼学报》2021,(4)
The genus Pyropia contains several important cultivated species.Genetic research in nori species has mainly focused on the cell nucleus,with few studies on organelles(chloroplast and mitocho ndria).Due to the high copy numbers of organelles in cells,which influence the development and traits of algae,it is necessary to study their genetic mechanism.In this study,the marine red alga yezoensis,an important economic macroalga,was selected as the study object.To investigate organelle(chloroplast and mitochondria) inheritance in P yezoensis,the wild type RZ(maternal strain) was cro ssed with the red mutant HT(paternal strain) and 30 color-sectors from 11 F1 gametophytic blades were examined.The complete chloroplast and mitochondrial genomes of the red mutant(HT) were assembled for the first time.One reliable and stable single nucleotide polymorphism(SNP) loci filtrated by bioinformatics analysis was used as a molecular marker for chloroplast and mitochondrial DNA,respectively,in subsequent experiments.PCR amplification and sequence analysis showed that the haplotypes of color-sectors detected were consistent with those of the maternal parent,confirming that both chloroplast and mitochondrial genomes were inherited maternally in P.yezoensis.The inheritance pattern of organelles in P.yezoensis can be used to guide the hybridization and breeding of nori.Additionally,the organelle SNP markers developed in this study can be applied in subsequent genetic research. 相似文献
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Journal of Oceanology and Limnology - The genus Neglectella Vodenicarov & Benderliev has a morphology similar to the well-known genus Oocystis, except for the numerous chloroplasts stacked... 相似文献