Mitochondrial Targeting in an Anti-Austerity Approach Involving Bioactive Metabolites Isolated from the Marine-Derived Fungus Aspergillus sp.     

Waleed A Abdel-Naime  Atsushi Kimishima  Andi Setiawan  John Refaat Fahim  Mostafa A. Fouad  Mohamed Salah Kamel  Masayoshi Arai 《Marine drugs》2020,18(11)

The tumor microenvironment is a nutrient-deficient region that alters the cancer cell phenotype to aggravate cancer pathology. The ability of cancer cells to tolerate nutrient starvation is referred to as austerity. Compounds that preferentially target cancer cells growing under nutrient-deficient conditions are being employed in anti-austerity approaches in anticancer drug discovery. Therefore, in this study, we investigated physcion (1) and 2-(2′,3-epoxy-1′,3′,5′-heptatrienyl)-6-hydroxy-5-(3-methyl-2-butenyl) benzaldehyde (2) obtained from a culture extract of the marine-derived fungus Aspergillus species (sp.), which were isolated from an unidentified marine sponge, as anti-austerity agents. The chemical structures of 1 and 2 were determined via spectroscopic analysis and comparison with authentic spectral data. Compounds 1 and 2 exhibited selective cytotoxicity against human pancreatic carcinoma PANC-1 cells cultured under glucose-deficient conditions, with IC₅₀ values of 6.0 and 1.7 µM, respectively. Compound 2 showed higher selective growth-inhibitory activity (505-fold higher) under glucose-deficient conditions than under general culture conditions. Further analysis of the mechanism underlying the anti-austerity activity of compounds 1 and 2 against glucose-starved PANC-1 cells suggested that they inhibited the mitochondrial electron transport chain.  相似文献   

Horizontal movement and emigration of juvenile spotted halibut <Emphasis Type="Italic">Verasper variegatus</Emphasis> released in a shallow brackish lagoon: Matsukawa-ura,northeastern Japan,revealed by acoustic telemetry     

Toshihiro Wada  Kyoichi Kamiyama  Hiromichi Mitamura  Nobuaki Arai 《Fisheries Science》2017,83(4):573-585

To elucidate the post-release movement and emigration of juvenile spotted halibut Verasper variegatus, ten hatchery-reared age-0 individuals (10 months old, 17.0–19.7 cm total length) surgically implanted with acoustic transmitters were released near the center of Matsukawa-ura, a shallow brackish lagoon, on 25 November 2009 (water temperature 13.8 °C). They were monitored by ten acoustic receivers for 5 months. Of ten individuals, eight left the release site during December–March. Three of these emigrated to the outer ocean on 17 and 29 January and 30 March 2010, respectively. Juveniles probably started wintering migration in December and January when water temperatures decreased considerably in the lagoon (mean 9.5 and 6.0 °C, respectively). They stopped their migration in the coldest month, February (mean 5.7 °C), and restarted it in March when water temperatures frequently exceeded a plausible threshold for movement (≥6 °C). Statistical analyses revealed that the fish started migration significantly more frequently at nighttime. The migration track of an individual recorded from 11 to 30 March showed gradual nocturnal movements and a slow migration speed (estimated maximum speed 2.2 m/min). Our results revealed that water temperature primarily governed the seasonal timing of nocturnal migratory movements of juvenile spotted halibut.  相似文献   

Discovering the dominance of the non-native European eel in the upper reaches of the Tone River system,Japan     

Kohma Arai  Hikaru Itakura  Akihito Yoneta  Tatsuki Yoshinaga  Fumiaki Shirotori  Kenzo Kaifu  Shingo Kimura 《Fisheries Science》2017,83(5):735-742

To investigate the presence of non-native anguillid eels in Japanese waters, 141 eels were collected from seven sampling sites throughout the Tone River system. Genetic species identification showed an extraordinary dominance of the non-native European eel Anguilla anguilla in the uppermost site of the study area. Estimation of age from otoliths suggested that the European eels were introduced into the river in the 1990s, corresponding to previous reports from other Japanese water systems. Comparison of the von Bertalanffy growth curve parameters indicated that the European eels caught in the Tone River system appeared to have a similar or even higher growth rate than the same species in the original habitats in Europe. The long-term inhabitation and the normal development of European eels in Japanese waters suggest that regulations prohibiting the release of non-native eels and safeguards against accidental escape from culture ponds must be strictly maintained in order to ensure the conservation of the native Japanese eel.  相似文献   

Development of nuclear DNA markers to characterize genetically diverse groups of <Emphasis Type="Italic">Misgurnus anguillicaudatus</Emphasis> and its closely related species     

Takafumi Fujimoto  Aya Yamada  Yukihiro Kodo  Kohei Nakaya  Michiko Okubo-Murata  Taiju Saito  Kazuto Ninomiya  Michiko Inaba  Masamichi Kuroda  Katsutoshi Arai  Masaru Murakami 《Fisheries Science》2017,83(5):743-756

Repetitive DNA sequences, ManDra and ManBgl, were isolated from the DraI and BglII digests of the genomic DNA of Misgurnus anguillicaudatus, respectively. A primer set of ManDra distinguished two genetically different groups (A and B) of M. anguillicaudatus by specific electrophoretograms. A primer set of ManBgl amplified the DNA of M. anguillicaudatus and M. mizolepis. The individuals of M. anguillicaudatus were divided into two groups depending on the fragment sizes, in which the groups A and B (B-1 and B-2) showed 400 and 460 bp, respectively. M. mizolepis was distinguished by a different pattern (400-, 460-, and 510-bp fragments). PCR–RFLP analyses of recombination activating gene 1 gave a clear difference between A or B-2 (443-bp fragment) and B-1 groups (296- and 147-bp fragments). Clonal lineages and hybrids between B-1 and B-2 groups could be identified by appearance of three fragments (443, 296, and 147 bp). The combined analyses using the above three nuclear markers discriminated among nuclear genomes of genetic groups (A, B-1 and B-2) of M. anguillicaudatus and M. mizolepis. In several localities, natural hybridizations between the group B-1 and B-2 loaches and introgressions of clonal mitochondrial genomes into the group B-1 loaches were detected.  相似文献   

Single spaghetti tagging as a high-retention marking method for Japanese common sea cucumber <Emphasis Type="Italic">Apostichopus japonicus</Emphasis>     

Takumi Fujino  Hideki Sawada  Hiromichi Mitamura  Reiji Masuda  Nobuaki Arai  Yoh Yamashita 《Fisheries Science》2017,83(3):367-372

Populations of sea cucumbers, including the Japanese common sea cucumber Apostichopus japonicus, have been seriously depleted worldwide due to overfishing. Mark–recapture study is an efficient means of collecting ecological data. However, the use of such a method in sea cucumbers is difficult because they lack hard tissues in the body wall. Here we tested the viability of various tagging methods on A. japonicus. First, we applied conventional tags using four different methods [single spaghetti (T-bar) tagging, double spaghetti tagging, ribbon tagging, and Atkins tagging] to ten individuals per method in aquaria for 14 days. Of the methods used, single spaghetti tagging had the highest retention rate. Then we examined the retention rate of single spaghetti tags on ten individual sea cucumbers for up to approximately 6 months in rearing conditions. The single spaghetti tagging method showed a retention rate of 100% over at least 7 days, and 50% of the tags remained embedded after 56 days. The longest duration of tag retention was 174 days, at which time the experiment was terminated. These results indicate that single spaghetti tagging is reliable for both short- and longer-term studies, making it a useful tool for ecological and conservation studies in sea cucumbers.  相似文献   

Spontaneous polyploidization in critically endangered <Emphasis Type="Italic">Acipenser mikadoi</Emphasis>     

Miloš Havelka  He Zhou  Seishi Hagihara  Masaki Ichimura  Takafumi Fujimoto  Etsuro Yamaha  Shinji Adachi  Katsutoshi Arai 《Fisheries Science》2017,83(4):587-595

We investigated the source of spontaneous polyploidization in the critically endangered Acipenser mikadoi. Fourteen sib progeny of A. mikadoi and 11 hybrids between an A. mikadoi female and a Huso dauricus male, all showing atypically high ploidy, were analysed. Parent assignment based on five highly polymorphic microsatellite markers confirmed spontaneous duplication of maternal chromosome sets via retention of the second polar body to be the source of spontaneous polyploidization. To our knowledge, this provides the first evidence of the maternal origin of spontaneous polyploidization in A. mikadoi. Factorial correspondence analysis of the multilocus microsatellite genotypes placed the parent fish of spontaneous polyploids in clearly delineated clusters of A. mikadoi and H. dauricus, and parent fish had mitochondrial control region haplotypes corresponding to their presumed species. Thus, parent fish were confirmed to be of pure genetic origin, and hybridization did not promote the observed spontaneous polyploidization.  相似文献   

日本柑橘黄龙病病原体电镜观察及PCR检测   总被引：3，自引：3，他引：0  

王运生  戴良英  荒井啓 《湖南农业大学学报(自然科学版)》2004,30(5):446-449

对日本柑橘黄龙病病原体的形态结构进行了电镜观察,结果发现柑橘黄龙病病菌日本株系绝大多数是球形和短椭圆形,极少观察到棒状形态,直径为100～500nm,外被一层胶状物质包围,厚约10～50nm,这与其他地区发现的柑橘黄龙病病原体形态不同．PCR检测表明,以硅藻土法提取的DNA为模板,利用Ready-To-Go^TM PCR bead法可以得到理想结果。  相似文献   

Effect of shelter acclimation on the post-release survival of hatchery-reared black-spot tuskfish <Emphasis Type="Italic">Choerodon schoenleinii</Emphasis>: laboratory experiments using the reef-resident predator white-streaked grouper <Emphasis Type="Italic">Epinephelus ongus</Emphasis>     

Yuuki Kawabata  Kimio Asami  Masato Kobayashi  Taku Sato  Koichi Okuzawa  Hideaki Yamada  Kenzo Yoseda  Nobuaki Arai 《Fisheries Science》2011,77(1):79-85

A critical component of many releasing projects is the identification and subsequent implementation of optimal release strategies that can decrease post-release predation mortalities. We performed laboratory experiments to investigate whether acclimation to shelters affects the post-release survival of hatchery-reared black-spot tuskfish Choerodon schoenleinii in the presence of a reef-resident predator, the white-streaked grouper Epinephelus ongus. Tuskfish were exposed to groupers under three different experimental conditions/treatments: (1) acclimation of fish to shelters prior to their exposure to groupers; (2) no acclimation of fish to shelters, but with shelters available during their exposure to groupers; (3) fish not acclimated to shelters and no shelters available during their exposure to groupers. Tuskfish that were acclimated to shelters utilized shelters more frequently than did non-acclimated fish, and the survival rate of acclimated fish was higher than those of fish in the other treatments. These results suggest that pre-release acclimation to shelters improves the post-release survival of hatchery-reared black-spot tuskfish.  相似文献   

Fractional determination of functional groups of humic acids by conductometric titration     

Shigemitsu Arai  Kyoichi Kumada 《Geoderma》1977,19(4):307-317

The conductometric replacement titration proposed in a previous report disclosed that the functional groups of humic acids are fractionated into three clusters of different dissociation constants, designated as VW, W and S clusters. In this paper, the method was examined to ascertain the relationship between the concentration of a sample and the amounts of fractionated clusters. The total amounts of fractionated clusters as well as the amount of the S cluster were directly proportional to the concentration of the sample, whereas the amount of the VW cluster decreased a little as concentration increased. The same method, applied to various types of humic acids in Japan, showed that the sums of the functional groups and the ratios of the S cluster to the sums likewise decreased in the order of A type > B and P types > Rp type. The total acidities determined by conductometry were nearly equal to the sums of carboxyl determined by Blom's method and phenolic hydroxyl determined by Folin's method.  相似文献   

Relationship Between Physicochemical Properties of Starches and White Salted Noodle Quality in Japanese Wheat Flours     

Takahiro Noda  Takuji Tohnooka  Shozo Taya  Ikuo Suda 《Cereal Chemistry》2001,78(4):395-399

This study describes the effect of starch properties of Japanese wheat flours on the quality of white salted noodles (WSN). Starch was isolated from 24 flours of 17 Japanese cultivars and amylose content was determined along with pasting properties by Rapid Visco Analyser (RVA), thermal properties by differential scanning calorimetry (DSC), and the distribution of amylopectin chain length by high‐performance anion exchange chromatography (HPAEC). Twenty flours were used to prepare WSN. As expected, 5–6% lower amylose content was associated with good WSN quality (higher scores in softness, elasticity, and smoothness). RVA analysis indicated that the pasting temperature had the greatest influence on WSN quality, while breakdown and setback showed slight effects on WSN quality. DSC results showed that lower endothermal enthalpy (ΔH) in the amylose‐lipid complex was associated with good WSN quality. Chainlength distribution of amylopectin by HPAEC was not an important factor in relation to WSN quality.  相似文献