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Recent research on decapod crustaceans revealed the presence of multiple vitellogenin genes within a single species. Characterizing their expression dynamics and regulatory mechanisms is helpful for the sustainability of commercially relevant decapods through a greater comprehension of vitellogenesis. However, it is unclear whether multiple vitellogenin genes exist in the kuruma prawn Marsupenaeus japonicus, an essential species in several Asian countries. This study determined the full-length cDNA sequence of the new vitellogenin (Maj-Vg2) using transcriptome analysis and cDNA cloning. The deduced Maj-Vg2 consisted of 2,554 amino acids and shared only 53.8% identity with Maj-Vg1, the known vitellogenin of this species. The Maj-Vg1 gene (Maj-Vg1) was expressed in both the hepatopancreas and ovary, whereas the Maj-Vg2 gene (Maj-Vg2) was expressed only in the hepatopancreas. Maj-Vg2 expression in the hepatopancreas was low during the previtellogenic stage and increased during the early and late yolk globule stages. When eyestalks were ablated from immature prawns, Maj-Vg2 expression in the hepatopancreas increased significantly, like Maj-Vg1 expression in the ovary, suggesting possible regulation by hormones from the eyestalk ganglia. These results suggested that Maj-Vg2 and Maj-Vg1 are involved in vitellogenesis in this species. [ABSTRACT FROM AUTHOR]

The immunomodulating effect of phlorotannin was investigated in mice stimulated by ovalbumin. When analyzing the main components of phlorotannin concentrate (PTC) from Eisenia nipponica, seven phlorotannins [eckol, 6,6′-bieckol, 6,8′-bieckol, 8,8′-bieckol, dieckol, phlorofucofuroeckol (PFF)-A, and PFF-B] were detected. These phlorotannins accounted for approximately 80% of PTC. Oral administration of PTC to mice daily for 21 days reduced serum immunoglobulin E (IgE) and total IgG1 levels attributable to Th2 cells. The production of splenic cytokines [interleukin (IL)-10 and transforming growth factor-β1] and Treg cell-mediated expression of forkhead box protein P3 mRNA were significantly increased whereas the production of inflammatory cytokines (interferon-γ, IL-4, IL-5, and IL-17) by Th1, Th2, and Th17 cells was markedly suppressed. IL-21 production and basic leucine zipper ATF-like transcription factor mRNA expression attributable to follicular helper T (Tfh) cells were also suppressed. Flow cytometric analyses demonstrated increased number of Treg cells despite a decrease in the total T cell population. An increase in total B cells was also observed by the flow cytometric analyses in addition to increases in IL-10 production, which activates B cells. In contrast, the significantly suppressed production of inflammatory cytokines and moderate increase in Treg cell subpopulation indicated a direct impact of PTC on inflammatory lymphocytes (Th1, Th2, Th17, and Tfh). Thus, PTC may exert antiallergic effects by immunomodulation of T cells and inactivation of inflammatory lymphocyte. [ABSTRACT FROM AUTHOR]

Molecules related to the insulin signaling pathway are widely conserved in the animal kingdom and are responsible for the regulation of various biological functions including growth, metabolism, and reproduction. Information on insulin-like peptides (ILPs) is, however, limited to insulin-like androgenic factor (IAG) in crustaceans. To date, in the kuruma prawn Marsupenaeus japonicus, only Maj-IAG, which is thought to be a crustacean androgen, and ovarian-specific Maj-ILP1 are the only members of the insulin family that have been reported. In this study, we identified two additional ILPs, Maj-ILP2 and Maj-gonadulin (Maj-GON), from the transcriptome data of M. japonicus. Maj-ILP2 gene expression was observed in the brain ganglia of both sexes and testis, while Maj-GON gene expression was limited to the testis. A more detailed tissue expression analysis of three male-dominant ILPs showed clear site-specific gene expression patterns in the gonads: Maj-ILP2 in the testis, Maj-GON in the vas deferens, and Maj-IAG in the androgenic gland attaching to the seminal vesicle. The results of this study show that, in addition to Maj-IAG, a crustacean androgen, there are two more ILP molecular species in the male gonad of M. japonicus, and suggest that they may serve as signaling molecules involved in the regulation of some male-specific functions. [ABSTRACT FROM AUTHOR]

The gold and cream colors of cultured Akoya pearls, as well as natural yellow nacre of pearl oyster shells, are thought to arise from intrinsic yellow pigments. While the isolation of the yellow pigments has been attempted using a large amount of gold pearls, the substance concerned is still unknown. We report here on the purification and characterization of yellow pigments from the nacre of Akoya pearl oyster shells. Two yellow components, YC1 and YC2, were isolated from the HCl-methanol (HCl-MeOH) extract from nacreous organic matrices obtained by decalcification of the shells with ethylenediaminetetraacetic acid (EDTA). Energy-dispersive X-ray and infrared spectroscopy analyses suggested that YC1 and YC2 precipitated under basic conditions are composed of Fe-containing inorganic and polyamide-containing organic compounds, respectively. YC1 solubilized under acidic conditions exhibited positive reactions to KSCN and K4[Fe(CN)6] reagents, showing the same ultraviolet-visible absorption spectrum as those of Fe(III)-containing compounds. In addition, X-ray absorption fine structure analysis supported the compound in the form of Fe(III). The total amount of Fe was approximately 2.6 times higher in the yellow than white nacre, and most Fe was fractionated into the EDTA-decalcifying and HCl-MeOH extracts. These results suggest that Fe(III) coordinated to EDTA-soluble and insoluble matrix compounds are mainly associated with yellow color development not only in the Akoya pearl oyster shells but also in the cultured Akoya pearls. [ABSTRACT FROM AUTHOR]

Color is one of the most important factors determining the commercial value of pearls. Pinctada fucata is a well-known pearl oyster producing high-quality Akoya pearls. Phenotypic variation in amount of yellow pigmentation produces white and yellowish pearls. It has been reported that polymorphism of yellow pigmentation of Akoya pearls is genetically regulated, but the responsible gene(s) has remained unknown. Here, we prepared pearl sac pairs formed in the same recipient oyster but coming from donor oysters that differ in their color. These two pearl sacs produced pearls with different yellowness even in the same recipient oyster. Yellow tone of produced pearls was consistent with shell nacre color of donor oysters from which mantle grafts were prepared, indicating that donor oysters strongly contribute to the yellow coloration of Akoya pearls. We also conducted comparative RNA-seq analysis and retrieved several candidate genes involved in the pearl coloration. Whole gene expression patterns of pair sacs were not grouped by pearl color they produced, but grouped by recipient oysters in which they were grown, suggesting that the number of genes involved in the yellow coloration is quite small, and that recipient oyster affects gene expression of the majority of genes in the pearl sac. [ABSTRACT FROM AUTHOR]

DUR3 proteins mediate high-affinity transport of exogenous and endogenous urea. Although two DUR3-like genes ( PyDUR3.1/ 3.2) have been identified in Pyropia yezoensis, a BLAST search using these sequences against the P. yezoensis EST database suggested the existence of another DUR3-like gene ( PyDUR3.3). In this study, the PyDUR3.3 gene was isolated and characterized and compared to PyDUR3.1/3.2 genes. The predicted length of PyDUR3.3 was 679 amino acids, which included 15 transmembrane domains. An amino acid sequence alignment of algal, plant, and yeast DUR3 proteins showed that PyDUR3.3 was more similar to PyDUR3.2 than to other DUR3 proteins, including PyDUR3.1. Exon-intron structures of PyDUR3.3 and PyDUR3.2 were also closely related to each other, which clearly differed from that of PyDUR3.1. Expression analysis showed that PyDUR3.3 mRNA levels were extremely high in sporophytes, regardless of the nutrient condition, compared to gametophytes. On the other hand, expression of PyDUR3.2 and PyDUR3.1 was high in the gametophytes and sporophytes, respectively, and was induced by nutrient starvation. These results suggest that expression of PyDUR3.3/3.2/3.1 depends on the life history phase as well as the nutrient conditions, and that PyDUR3.3 and PyDUR3.2 are paralogues specifically differentiated in function and life history phase. [ABSTRACT FROM AUTHOR]

The potential use of deep seawater (DSW) for the cultivation of macroalgae was evaluated by analysis of the growth rate of thalli (by surface area), photosynthetic pigment content, and total free amino acid content of sterile Ulva pertusa cultured in the control medium (one-fifth strength Provasoli's enriched seawater (PES) medium), surface seawater (SSW) medium and also seawater medium collected from 400 m depth (400-DSW) and 1,200 m depth (1,200-DSW). The growth rate of the sterile U. pertusa grown in 400-DSW and 1,200-DSW was similar to that of thalli cultured in the one-fifth strength PES medium that had previously been shown to be the optimum concentration for the cultivation of Ulva. Photosynthetic pigment content in the control medium, 400-DSW- and 1,200-DSW-cultured thalli was 1.7-2.0 times higher than that of the SSW-cultured thalli. The total free amino acids content of the control medium and SSW-cultivated thalli was 264 ± 64 and 120 ± 39 mg per 100 g dry weight, whereas the 400-DSW- and 1,200-DSW-cultivated thalli had significantly more amino acids (342 ± 69-327 ± 64 mg per 100 g dry weight). The results of this study indicate that DSW has a high potential for cultivation of edible macroalgae without any supply of extra nutrient until it grows to harvest size. [ABSTRACT FROM AUTHOR]

Molecular chaperones are synthesized and accumulated under a variety of unfavorable conditions in all organisms. Heat shock protein 90 (Hsp90) and Hsp60, which are classified into the major classes of molecular chaperones, play important roles in cellular stress responses. In this study, we characterized sterile Ulva pertusa Hsp90 ( UpHsp90) and UpHsp60 genes which may be involved in tolerance to thermal and heavy metal stresses in this alga. The UpHsp90 cDNA consisting of 2,118 nucleotides encoded a polypeptide of 705 amino acids (AA). On the other hand, the UpHsp60 cDNA consisting of 1,722 nucleotides encoded a protein whose predicted length was 573 AA. The AA sequence alignment and phylogenetic analyses showed that the UpHsp90 and UpHsp60 proteins were more similar to cytoplasmic Hsp90s and mitochondrial Hsp60s, respectively, than to other types of the respective Hsps. Southern blot analysis indicated that the sterile U. pertusa genome had at least two cytoplasmic Hsp90-encoding genes and two mitochondrial Hsp60-encoding genes. The UpHsp90 and UpHsp60 mRNA levels were significantly affected by diurnal and temperature changes, and slightly affected by exposure to heavy metals. These results suggest that UpHsp90 and UpHsp60 genes play particularly important roles in adaptation to diurnal and temperature changes. [ABSTRACT FROM AUTHOR]

Synthesis and accumulation of molecular chaperones are universal responses found in all cellular organisms when exposed to a variety of unfavorable conditions. Heat shock protein 70 (Hsp70), which is one of the major classes of molecular chaperones, plays a particularly important role in cellular stress responses, and the Hsp70 system is the most intensely studied in higher plants and algae. Therefore, we isolated and characterized a cDNA clone encoding Hsp70 from a sterile strain of Ulva pertusa (Ulvales, Chlorophyta). The sterile U. pertusa Hsp70 (UpHsp70) cDNA consisted of 2,272 nucleotides and had an open reading frame encoding a polypeptide of 663 amino acid (AA) residues with a molecular mass of 71.7 kDa. Amino acid alignment and phylogenetic analysis of Hsp70s from other organisms showed that UpHsp70 was more similar to cytoplasmic Hsp70s from green algae and higher plants (≥75%) than to those from other algae and microorganisms. Southern blot analysis indicated that the sterile U. pertusa genome had at least four cytoplasmic Hsp70-encoding genes. UpHsp70 mRNA levels were significantly affected by diurnal changes, rapidly increased by high-temperature stress, and gradually increased by exposure to copper, cadmium, and lead. These results suggest that UpHsp70 plays particularly important roles in adaptation to high-temperature conditions and diurnal changes, and is potentially involved in tolerance to heavy metal toxicity. [ABSTRACT FROM AUTHOR]

We isolated two different genomic DNAs ( UprbcS1 and UprbcS2) encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase and portions of the 5′- and 3′-flanking regions from sterile Ulva pertusa Kjellman. The UprbcS1 and UprbcS2 genes had three introns in the coding region. Each predicted UprbcS polypeptide was a 180-amino-acid (AA) residue including a 38-AA transit peptide, although the 104th AA residue was replaced. The nucleotide sequences of UprbcS cDNAs isolated from a cDNA library corresponded to that of the UprbcS1 gene, suggesting that the UprbcS1 gene was predominantly expressed in sterile U. pertusa compared to UprbcS2. Southern blot analysis showed that each UprbcS gene was a single-copy gene in the sterile U. pertusa genome. Northern hybridization indicated that the expression of UprbcS was induced and repressed by dark and light treatments, respectively. When sterile U. pertusa cells were transformed with an expression vector containing the UprbcS1 promoter and terminator sequences fused with the green fluorescent protein ( GFP) gene, GFP fluorescence was observed in the cells transformed. These results suggest that the UprbcS1 gene promoter is light regulated and highly active in the sterile U. pertusa cells and is available for genetic transformation system in the alga. [ABSTRACT FROM AUTHOR]

To investigate the anti-allergic effects of the brown alga Eisenia arborea. A strain of Brown Norway rats known to strongly respond to immunoglobulin E (IgE) were used as an allergy model animal. The rats were immunized with ovalbumin by oral administration. The levels of serum IgE and histamine were suppressed in the rats fed a diet supplemented with dried E. arborea powder. As for the cytokine pattern, the interferon-γ production in the spleens and mesenteric lymph nodes (MLN) was enhanced, and the interleukin-4 (IL-4) production in the spleens and/or IL-10 production in the spleens and MLN were suppressed. These results, together with the change in the Th1/Th2 balance, indicate that the rats fed with E. arborea became more anti-allergic, suggesting that E. arborea might possess anti-allergic effects. [ABSTRACT FROM AUTHOR]

The effects of 80% methanol extracts from frozen samples of 41 macroalgae and one sea grass collected in the Ise-Shima region of Japan were investigated on histamine release from rat basophile leukemia cells (RBL-2H3) sensitized with antidinitrophenyl (DNP) IgE and stimulated with DNP-BSA. Of the 21 brown algae, five green and 15 red algae, and one sea grass tested, only extracts from seven brown algae suppressed histamine release from RBL cells, as determined by high-performance liquid chromatography (HPLC) analysis. When the cytotoxic effects of the seven brown algal extracts were investigated by Trypan blue staining, only Eisenia arborea and Sargassum thunbergii did not show cytotoxic effects. Therefore, we conclude that E. arborea and S. thunbergii may contain compounds that have antiallergic effects without inducing cell death. [ABSTRACT FROM AUTHOR]

To assess the effect of a seaweed mixture on lipid levels in serum as well as platelet aggregation in rats, Eisenia bicyclis (‘Arame’), Hizikia fusiformis (‘Hijiki’) and Undaria pinnatifida sporophylls (‘Mekabu’), all brown seaweeds, and Porphyra yezoensis (‘Susabinori’), a red seaweed, were powdered and mixed in a ratio of 45:30:20:5 (w/w). When rats were fed a cholesterol-rich diet containing this mixture of seaweeds (9–10% w/w) for 28 days, serum total cholesterol, LDL-cholesterol, free cholesterol, and triglyceride levels declined significantly to 49.7%, 48.1%, 49.0% and 74.8%, respectively, of those of the control. Serum HDL-cholesterol, however, was unchanged. Though activated partial thromboplatin time, prothrombin time, antithrombin III activity, and fibrinogen levels in plasma were unchanged, the maximal ADP- and collagen-induced platelet aggregation decreased significantly to 89.0% and 85.5% control levels, respectively. These results indicate that this mixture of E. bicyclis, H. fusiformis, U. pinnatifida sporophylls, and P. yezoensis, is useful for the prevention of hyperlipidemia and thrombosis in rats. [ABSTRACT FROM AUTHOR]

Genetic variation of the fungal parasite Pythium porphyrae ,causative organism of red rot disease of Porphyra , isolatedfrom Asan, Mokpo, Pusan and Wando in Korea, and from Aichi, Fukuokaand Miyagi in Japan was investigated by random amplified polymorphicDNA (RAPD) cluster analysis. The total 67 RAPD markers were generatedfrom 38 isolates by RAPD-polymerase chain reaction (PCR) using arbitraryprimers consisting of 10 nucleotide sequences and 33 of them indicatedpolymorphisms. The dissimilarity coefficients calculated from theRAPD banding patterns ranged from 0.0010 to 0.6983. The dendrogramgenerated by the unweighted pair-group method using arithmetic averagesshowed that the 38 isolates were classified into three clusters(Groups 1, 2 and 3). Group 1 consisting of two isolates from Miyagiwas separated from all other isolates by a genetic distance of 0.6983.Groups 2 and 3 containing the majority of the isolates were branchedon genetic distance of 0.3957. These two clusters subdivided intofour and three subclusters, respectively, which were apparentlyassociated with geographic origins of the isolates. Interestingly,the isolates from Asan of Korea were close to Japanese isolatesrather than Korean isolates on genetic diversity. In addition, thegenetic distances of intra-isolates from Japan were higher thanthose from Korea. [ABSTRACT FROM AUTHOR]

The detection and quantitative analysis of Pythium porphyraezoospores was performed by PCR using PP-1 and PP-2 primers specific tothe internal transcribed spacer region of P. porphyrae. To estimatethe amount of fungal zoospores of P. porphyrae, an internal standardplasmid (pPPISC) containing a modified DNA fragment was constructed. Both ends of this fragment were complementary to the PCR primers. Amplification using primers PP-1 and PP-2 produced DNA fragments ofapproximately 700 and 400 bp from the target DNA of P. porphyraezoospores and from the pPPISC, respectively. To perform quantitativePCR, known quantities of pPPISC were added to reaction mixturescontaining the experimental DNAs extracted from zoospores. After aco-amplification reaction, the two different sized PCR products wereseparated by agarose gel electrophoresis and visualized by ethidium bromidestaining. The number of zoospores was estimated by comparing thefluorescence intensities of the PCR products using a charge-coupled deviceimage analyzer. The results show that competitive PCR using P.porphyrae specific primers and competitor pPPISC are useful tools for thequantitative analysis of P. porphyrae zoospores in seawater from Porphyra cultivation farms. [ABSTRACT FROM AUTHOR]

SUMMARY: The thermal stress responses of a sterile mutant of the marine alga Ulva pertusa were investigated at 20°C and 30°C. The amounts of the photosynthetic pigments, β-carotene, chlorophylls a and b, lutein, neoxanthin, and violaxanthin, were 1.4–2.4 times higher in the 30°C-cultivated alga than in the 20°C-cultivated alga. The free amino acids, asparagine, aspartic acid, glutamine, glutamic acid, glycine, and serine, were abundant in the 20°C-cultivated alga, and increased 1.9–10.5-fold in response to thermal stress (30°C). Total carbon and nitrogen contents also increased in the 30°C-cultivated alga. Sodium dodecylsulfate-polyacrylamide gel electrophoretic patterns of total proteins extracted from both temperature-treated algae showed the increases of 20, 25, and 90 kDa proteins in the 30°C-cultivated alga. Isozyme assays for 20 enzymes showed a different banding pattern only in the case of glutamate dehydrogenase (GDH). Although it was observed that both temperature-treated algae possessed NAD+- and NADP+-specific GDH, the 30°C-cultivated alga had an additional NADP+-specific GDH (NADP-GDH). These results suggest that NADP-GDH compensates for the thermally induced decreases in nitrogen assimilation efficiency and thereby regulates nitrogen metabolism under conditions of temperature stress. [ABSTRACT FROM AUTHOR]

A cDNA library constructed from the dorsal fast skeletal muscle of white croaker Pen-nahia argentata was screened for myosin heavy chain using antibody raised against carp fast skele-tal myosin. A full-length cDNA was further cloned by reverse transcription--PCR and 5-RACE using first-strand cDNA as a template together with appropriate sets of primers. The entire cDNA consisted of 5986 nucleotides (nt) with 64 nt 5-untranslated and 129 nt 3-untranslated regions. This full-length cDNA had an open reading frame encoding a polypeptide of 1930 amino acid residues. Amino acid alignment with myosins from various vertebrates revealed some striking differences between fish and mammalian sequences which could be due to their position in the vertebrate evolutionary process. Hydrophilicity analysis revealed two different features of the myosin molecule: S1 heavy chain showed a mixed profile of hydrophobicity and hydrophilicity, whereas rod had a profile of only hydrophilicity. Comparison of amino acid sequences in the rod region between white croaker and walleye pollack showed a markedly high identity of 92%. White croaker myosin rod had a charac-teristic seven-residue (heptad) repeat (a, b, c, d, e, f, g)n, where positions a and d were normally occupied by hydrophobic residues, and positions b, c and f by oppositely charged residues, which may lead to interhelical electrostatic attractions stabilizing the coiled-coil of a -helices. [ABSTRACT FROM AUTHOR]

Pythium sp., the causative organism of red rot disease, isolated from Porphyra yezoen-sis from Wando in Korea was compared with those from Miyagi, Aichi, and Fukuoka Prefectures by means of electrophoretic patterns of soluble proteins and isozymes. Native and sodium dodecyl-sulfate-- polyacrylamide gel electrophoretic patterns of soluble proteins revealed small but significant differences among the four isolates. Among the 14 detected enzymes, catalase (CAT), carboxyle-sterase (CE), glucose-6-phosphate dehydrogenase (G6PD), glucosephosphate isomerase (GPI), isocitrate dehydrogenase (IDH), malate dehydrogenase (MDH), superoxide dismutase (SOD), and xanthine dehydrogenase (XDH) possessed isozymes. The dissimilarity value of isozyme banding pat-terns for four isolates by unweighted pair-group method using arithmetic averages (UPGMA) cluster analysis was highest (0.51) between the isolate from Fukuoka and those from Miyagi and Aichi, and lowest (0.19) between the isolate from Miyagi and that from Aichi. Cluster analysis of data from isozyme banding patterns grouped the isolates from Miyagi and Aichi. These results indicate that the isolates from Miyagi and Aichi are similar, but each isolate from Wando and Fukuoka differed slightly from those of Miyagi and Aichi. [ABSTRACT FROM AUTHOR]

Discusses a study conducted by researchers in Japan, which found that the sterile Ulva pertusa exposed to hypersaline conditions accumulated an organic osmolytes proline such as other green macroalgae. Preparation of seawater media of low and high salinities by diluting natural seawater; Investigation of the changes in the chemical components such as photosynthetic pigments, free amino acids and total carbon and nitrogen in thalli exposed to extreme low and high salinities.

Characterizes complementary DNA clone encoding glutamate dehydrogenase in green alga, Ulva pertusa. Amino acid sequence; Nucleotide sequence; Expression of messenger RNA; Tissue distribution.

Examines the detection of the red rot disease fungi Pythium species by polymerase chain reaction (PCR). Analysis on the distribution of the Phythium sp.; Effectiveness of the PCR in detecting the red rot disease; Comparison between Pythium sp and other species.

Examines the distribution of free L-cysteine and glutathione in seaweeds. Function of glutathione; Degradation of glutathione during sulphur starvation; Significance of the unusual ratio of cysteine and glutathione.

Analyzes serum proteins derived from rainbow trout exposed to high temperature. Effect if temperature on the aquaculture of rainbow trout; Synthesis of heat shock proteins in fish cells; Increase of several protein bands.