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1.
Pyropia haitanensis (T. J. Chang et B. F. Zheng) N. Kikuchi et M. Miyata (Porphyra haitanensis) is an economically important genus that is cultured widely in China. P. haitanensis is cultured on a larger scale than Pyropia yezoensis, making up an important part of the total production of cultivated Pyropia in China. However, the majority of molecular mechanisms underlying the physiological processes of P. haitanensis remain unknown. P. haitanensis could utilize inorganic carbon and the sporophytes of P. haitanensis might possess a PCK-type C4-like carbon-fixation pathway. To identify microRNAs and their probable roles in sporophyte and gametophyte development, we constructed and sequenced small RNA libraries from sporophytes and gametophytes of P. haitanensis. Five microRNAs were identified that shared no sequence homology with known microRNAs. Our results indicated that P. haitanensis might posses a complex sRNA processing system in which the novel microRNAs act as important regulators of the development of different generations of P. haitanensis.  相似文献   

2.
Members of the Dna J family are proteins that play a pivotal role in various cellular processes, such as protein folding, protein transport and cellular responses to stress. In the present study, we identified and characterized the full-length Dna J c DNA sequence from expressed sequence tags of Pyropia yezoensis( Py Dna J) via rapid identification of c DNA ends. This c DNA encoded a protein of 429 amino acids, which shared high sequence similarity with other identified Dna J proteins, such as a heat shock protein 40/Dna J from Pyropia haitanensis. The relative m RNA expression level of Py Dna J was investigated using real-time PCR to determine its specific expression during the algal life cycle and during desiccation. The relative m RNA expression level in sporophytes was higher than that in gametophytes and significantly increased during the whole desiccation process. These results indicate that Py Dna J is an authentic member of the Dna J family in plants and red algae and might play a pivotal role in mitigating damage to P. yezoensis during desiccation.  相似文献   

3.
Microorganisms plays an important role in the growth of Pyropia haitanensis. To understand the structural and functional diversity of the microorganism community of P. haitanensis(PH40), the associated metabolic pathway network in cluster of orthologous groups(COG) and Kyoto Encyclopedia of Genes and Genomes(KEGG), and carbohydrate-active enzymes(CAZymes) were explored in metagenomic analysis. DNA extraction from gametophytes of P. haitanensis was performed first, followed by library construction, sequencing, preprocessing of sequencing data, taxonomy assignment, gene prediction, and functional annotation. The results show that the predominant microorganisms of P. haitanensis were bacteria(98.98%), and the phylum with the highest abundance was Proteobacteria(54.64%), followed by Bacteroidetes(37.92%). Erythrobacter(3.98%) and Hyunsoonleella jejuensis(1.56%) were the genera and species with the highest abundance of bacteria, respectively. The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category. The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community. Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules) were the other important pathways. The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms. Glycosyl transferase family 2(GT2) and glycosyl transferase family 3(GT3) were the highly abundant families in glucoside transferase superfamily. Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12) and indole-3-acetic acid were obtained by binning method. They were confirmed to belong to Rhodobacterales and Rhizobiales, respectively. Our findings provide comprehensive insights into the microorganism community of Pyropia.  相似文献   

4.
Members of the DnaJ family are proteins that play a pivotal role in various cellular processes, such as protein folding, protein transport and cellular responses to stress. In the present study, we identified and characterized the full-length DnaJ cDNA sequence from expressed sequence tags of Pyropia yezoensis (PyDnaJ) via rapid identification of cDNA ends. This cDNA encoded a protein of 429 amino acids, which shared high sequence similarity with other identified DnaJ proteins, such as a heat shock protein 40/DnaJ from Pyropia haitanensis. The relative mRNA expression level of PyDnaJ was investigated using real-time PCR to determine its specific expression during the algal life cycle and during desiccation. The relative mRNA expression level in sporophytes was higher than that in gametophytes and significantly increased during the whole desiccation process. These results indicate that PyDnaJ is an authentic member of the DnaJ family in plants and red algae and might play a pivotal role in mitigating damage to P. yezoensis during desiccation.  相似文献   

5.
Pyropia haitanensis poly saccharide(LP) have been found for having many excellent functions such as anti-aging.Using Caenorhabditis elegans models,we evaluated the anti-aging activity of LP by observing the lifespan,reproduction,pharyngeal pumping,stress response,quantitative fluorescence of poly glutamic acid,and nuclear localization of DAP-16 of worms.The results reveal that LP could extend the adult lifespan of wild-type and polyQ nematodes,indicating a connection of its anti-aging benefit with the toxicity-suppressing effect The number of polyglutamic acid aggregates in high concentration groups decreased by 24.39%(P0.05) to the control.The high-dose group strongly induced DAP-16 nuclear translocation over intermediate and cytosolic localizations compared with the control(P0.001).Therefore,we believe that LP could extend the lifespan and reduce the protein aggregation in C.elegans through nuclear DAF-16::GFP expression.  相似文献   

6.
Qiu  Liping  Mao  Yunxiang  Tang  Lei  Tang  Xianghai  Mo  Zhaolan 《中国海洋湖沼学报》2019,37(3):1102-1112
Pyropia yezoensis(formerly Porphyra yezoensis) is an economically important red alga that is cultured extensively in China. The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses. An incidence of red rot disease was found in a P. yezoensis farm from mid-November to mid-December 2015 at Lianyungang, Jiangsu Province, China. Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen, leading to red rot symptoms. The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox1). In artificial infection experiments on the P. yezoensis blades, the P. chondricola isolate was able to cause the same characteristic histopathology seen in natural infections. P. chondricola grew well at a wide range of temperatures in the range 8-31℃, salinities at 0-45 and pH 5-9. In an orthogonal test used to determine the effects of environmental factors(temperature, salinity, and zoospore concentration)on infection, the data revealed that temperature was the most important factor to affect red rot disease development, with the optimal conditions for disease expansion being 20℃, 35 salinity, and a zoospore concentration of 10~6 zoospores/mL. The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia, which will provide support to maintain the healthy development of the Pyropia industry in China.  相似文献   

7.
The structural feature of agar polysaccharides from Porphyra haitanensis grown in south China and transplanted to the north was investigated by fractioriation on DEAE - Sephadex A 50, chemical analysis, and infrared and 13C - NMR spectroscopy.The agars composed mainly of Charged molecules were eluted from DEAE - Sephadex A 50 with 1.0 mol/L- NaCl solution from the southern P. haitanensis and with 0.5 mol/L NaCl from the northern one. The 13C-NMR spectra showed that agarobiose [(1 -3)- B D - galactopyranosyl - (1 -4)-3,6-anhydro-a-L-galactopyranose] and the biological precursor of agarobiose [(1-3} B-D-galactopyra nosyl- (1-4)- 6- sulfate-a- L-galactopyranose ] were the major disaccharide repeating units in the charged fractions. The content of the biological precur sor in the agar polysaccharides from southern P. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than that from hot water, and the content of 6- OMe-D-galactos  相似文献   

8.
An improved method of PCR in which the small segment of conchocelis is amplified directly without DNA extraction was used to amplify a RUBISCO intergenic spacer DNA fragment from nine species of red algal genus Porphyra(Bangiales,Rhodophyta),including Porphyra yezoensis(Jiangsu,China),P.haitanensis(Fujian,China),P.oligospermatangia(Qingdao,China),P.katadai(Qingdao,China),P.tenera(Qingdao,China),P.suborboculata(Fujian,China),P.pseudolinearis(Kogendo,Korea),P.linearis(Devon,England),and P.fallax(Seattle,USA)....  相似文献   

9.
Isolated protoplasts from thalli of Porphyra haitanensis and Porphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV ). Several types of color variants were observed among the protoplast offspring. After treatment with colchicine: (1) 0.04-0.09% of red type variants in P. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were 6.31- 1.11% in P. yezoensis. After irradiation with UV: (1) 3.5- 10.5% of red type variants in P. yezoensis were obtained: (2) 0.5-2-0% of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were obtained in P. haitanensis. Colchicine and UV's mutangenic effects on P. yezoensis protoplasts were stronger than those on P. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation distance 5 cm). The red type variants induced, by colchicine tr  相似文献   

10.
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   

11.
The light demands of seaweeds is an interesting and rather complex phenomenon because they depend not only on the species but also on their different development stages. Even different parts of the same plant sometimes have different light demands. Light control is an important procedure at large scaleLaminaria nursery stations in China. Technicians and scientists have different viewpoints on the best method to regulate light. A culture study onLaminaria japonica starting from zoospores to several centimeter sporophytes to find the optimal and critical irradiance ranges for juvenileLaminaria at different development stages added more knowledge on this aspect. Experiment results show gametophytes can not tolerate irradiance of more than 150 μE m−2s−1 while sporophytes can tolerate more than 519 μE m−2s−1. This big difference starts from the very early stage of 1-to 2-celled sporophytes. The biological basis and mechanism of this phenomenon need further research. Contribution No. 1515 from the Institute of Oceanology, Academia Sinica Contribution No. 1 from the Experimental Marine Biological Laboratory  相似文献   

12.
Unicellular gametophytes ofUndaria pinnatifida (Harv.) Sur. were isolated in Qingdao, P. R. China in April 1993 and in Tokushima, southern Japan in March 1995. Different intraspecific crossings by using unicellular male and female gametophytes were successfully undertaken in Sept. of 1995 in Qingdao. Sporophytes were transplanted to two different locations for open sea cultivation. One was at Zhanqiao (ZQ) Bay where the water current was slower than that of another location—Taipingjiao(TPJ). A total of 218 adult sporophytes were harvested on January 12 and 18 from TPJ and ZQ respectively. For eacn combination, 10 sporophytes were cultivated. Analysis of the morphological characteristics of adult sporophytes indicated that the longest length between two bases of the serration of pinnate blades (W2) is a morphological characteristic that can be transferred from the parent plant to the next generations regardless of environmental variations. There was evidence that W2 was apparently determined by sex-linked factors, i.e., by male parental gametophyte. Sporophytes from certain crossing combinations showed more vigorous growth than those from other crossing combinations. It is therefore possible to select gametophyte strains which can be used as parental gametophytes for the seedling production of sporophytes with more vigorous growth within shorter cultivation period. The morphology of hybrids from a Qingdao strain and a Tokushima cultivated strain resembled that of both parental plants in frond features (wrinkled or smooth) and W2. Sporophyll formation also varied with strains. The fact that adult sporophytes resulting from the same crossing combinations have identical morphological characteristics under the same environmental conditions indicates the possibility of a new way to select strains which are expected to be ideal for commerical production by purposely selecting, propagating, and seeding unicellular gametophytes for sporeling production through freeliving techniques of gametophytes. Project 39400102 supported by NSFC, also supported by National Climbing Plan B (PD-B642); and Bioengineering Center, SSTC.  相似文献   

13.
Yang  Huichao  Yan  Yongwei  Li  Jie  Tang  Lei  Mao  Yunxiang  Mo  Zhaolan 《中国海洋湖沼学报》2020,38(1):168-176
Pseudoalteromonas marina is one of the potential pathogens that cause green spot disease(GSD) in Pyropia yezoensis. To prevent GSD from development and spread, an ef fective method to detect the pathogen at early GSD infection stages need to be established. In this research, PCR methods were established targeting the dnaA gene(encoding chromosome replication initiator protein) and the dnaN gene(encoding β sliding clamp of DNA polymerase Ⅲ protein) to detect P. marina with three primer pairs pws-dnaA 2(Forward, 5′-ACCGCATTAACGAACTACTCGTG-3′; Reverse, 5′-TGCCATTACCTACAGCATGG-3′), pcs-dnaN 2(Forward, 5′-CTTACAACGTTATCAGCGGC-3′; Reverse, 5′-GTTGAGTATTAAGTGATTGAGTAAGC-3′) or pws-dnaN 3(Forward, 5′-ACTTACAACGTTATCAGCGGC-3′; Reverse, 5′-ACTGCTGTTTGAGTCTGCTAAC-3′). Three PCR methods corresponding to the three primer pairs su ? ciently distinguished P. marina from 22 bacterial species, thus resulting in detection limits of 4 to 4×10 2 CFU cells or 2.37×10 1 to 2.37×10 3 fg of P. marina DNA per PCR reaction. In an arti?cial infection experiment of P. yezoensis infected with P. marina, all established PCRs successfully detected P. marina at early GSD infection stages. The results show that the established PCRs are speci?c and sensitive, and are potential for applications in early diagnosis of GSD in Pyropia.  相似文献   

14.
15.
Lobophora rosacea C.W. Vieira, Payri et De Clerck is reported from the South China Sea for the first time. Our specimens are very similar to L. rosacea recently described from New Caledonia, not only in morphology but also in rbcL and cox3 gene sequences. The fan-shaped thallus grows erectly, attaching to the substrate by a basal holdfast. The thallus is composed of a single layer of large medullary cells and three to four layers of cortical cells on both sides of the medulla. Mature sporophytes are detected, with sporangium sori scattered on both surfaces of the thallus.  相似文献   

16.
Porphyra haitanensis andP. yezoensis are two mainPorphyra species cultured in China. Their life histories are slightly different. So far we have not observed thatP. haitanensis naturally produces monospores developing into thalli.P. yezoensis produces monospores which directly germinate into young thalli used in cultivation (Zeng, et al., 1985). Some somatic cells inP. yezoensis develop in vitro into monospore-like cells which later grow into young thalli (Lu, 1983). Studies on whether or not somatic cells inP. haitanensis can produce in vitro monospore-like cells that later grow into young thalli is important for understanding its life history and for culturing new varieties.  相似文献   

17.
Results of the experiment of northward transplantation of Porphyra haitanensis showed thatintercrop of P. haitanensis with Bay Scallop is feasible because the growth duration of both of them is about the same in August - December.Full use of cultivating area, lowering its cost and increasing its product per unit area as well as improving the ecological envronment are realized during intercrop.  相似文献   

18.
Pyropia yezoensis, belongs to the genus of P orphyra before 2011, inhabit on intertidal zone rocks where irradiation changes dramatically, implying that the seaweed has gained certain mechanisms to survive a harsh environment. Based on the photosynthetic parameters with or without the inhibitors determined by a Dual-PAM-100 apparatus, we investigated the photosynthetic performance and the changes in electron fl ow that occurred during the algae were stressed with dif ferent light intensities previously. When the irradiation saturation was approaching, the CEF around PS I became crucial since the addition of inhibitors usually led to an increase in non-photochemical quenching. The inhibitor experiments showed that there were at least three dif ferent CEF pathways in Py. yezoensis and these pathways compensated each other. In addition to maintaining a proper ratio of ATP/NAD(P)H to support effi cient photosynthesis, the potential roles of CEF might also include the regulation of dif ferent photoprotective mechanisms in Py. yezoensis. Under the regulation of CEF, chlororespiration is thought to transport electrons from the reduced plastoquinone(PQ) pool to oxygen in order to mitigate the reduction in the electron transfer chain. When irradiation was up to the high-grade stress conditions, the relative value of CEF began to decrease, which implied that the NADP+ pool or PQ + pool was very small and that the electrons were transferred from reduced PS I to oxygen. The scavenging enzymes might be activated and the water-water cycle probably became an ef fective means of removing the active oxygen produced by the irradiation stressed Py. yezoensis. We believe that the dif ferent mechanisms could make up the photoprotective network to allow Py. yezoensis for survival in a highly variable light stress habitat, which may enlighten scientists in future studies on irradiance stress in other algae species.  相似文献   

19.
Chitosan is a natural cationic polysaccharide,which is often used for preparing biomedical materials because of its high biocompatibility.In this study,chitosan with a molecular weight of 160 k Da was chosen to prepare chitosan nanoparticles(CSNPs) as gene vectors by ionic cross-linking with tripolyphosphate(TPP).CSNPs were characterized in terms of particle size,zeta potential,and polydispersity index(PDI) using a Zetasizer,and morphology was evaluated by transmission electron microscopy(TEM).Furthermore,the cytotoxicity and biocompatibility of CSNPs were correspondingly examined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay and histological examination.Agarose gel electrophoresis and UV spectrophotometric methods were performed to measure the loading capacity.The cell transfection efficiency of CSNPs loaded with plasmids or si RNA was analyzed by fluorescence microscopy or laser scanning confocal microscopy.The results showed that CSNPs were prepared successfully by the ionic gelation method,which had a smaller particle size(100 nm-200 nm),stable dispersibility,low cytotoxicity,good tissue-biocompatibility,and high gene-loading efficiency.These CSNPs could transfer the plasmids or si RNA to cells.However,CSNPs might have a much higher transfection efficiency for si RNAs than for plasmids,which implies that CSNPs might be a safer and more efficient vector for delivering si RNAs rather than plasmids.  相似文献   

20.
Song  Qin  Peng  Jiang  Xin-ping  Li  Xi-hua  Wang  Cheng-kui  Zeng 《中国海洋湖沼学报》1998,16(1):50-55

A genetic transformation model for the seaweedLaminaria japonica mainly includes the following aspects:

  1. 1.

    The method to introduce foreign genes into the kelp,L. japonica

    Biolistic bombardment has been proved to be an effective method to bombard foreign DNA through cell walls into intact cells of both sporophytes and gametophytes. The expression ofcat andlacZ was detected in regenerated sporophytes, which suggests that this method could induce random integration of foreign genes.

    Promoters to drive gene expression

  2. 2.

    The CaMV35S promoter was first used by us to induce the expression of GUS gene in brown algae. But results of further studies suggested that CaMV35S could be a tissue-specific promoter. Our use of SV40 promoter resulted in both transient and stable expression oflacZ andcat in sporophytes or gametophytes. No GUS or LacZ background was found in either sporophytes or gametophytes.The regeneration route of transgenic kelp

    The regeneration efficiency of explants is still very low. By using female gametophytes as gene hosts and parthenogenesis as regeneration route, CAT activity and LacZ activity were detected in regenerated sporophytes of parthenogenetic kelp. li]4.|The way to select transgenic kelp

  3. 1.

    Results of sensitivity tests showed that kelp was only sensitive to chloramphenicol and hygromycin among many antibiotics. The regenerated sporophytes by parthenogenesis were more sensitive to hygromycin than to chloramphenicol. Resistant kelp was created by transforming female gametophytes with pSV40-CAT and stimulating parthenogenesis followed by selection in medium with lethal concentration of chloramphenicol.

    Safety consideration of transgenic kelp

    L. japonica was originally introduced from Japan. In China it is a cultured population. The possibility of its negative impact on natural populations is very low. 2) The vectors and target genes used for transformation should be restricted in order to avoid any negative impacts on human health and environment. 3) Specially devised containers (3.6 L, made of 200 μm membrane) were used to ensure that the kelp cannot escape or be eaten by marine animals. 4) To avoid the release of spores, it is very necessary to harvest the kelp at suitable age before the sporangium forms.

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