http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Atsushi HAGIWARA (검색결과 20 건)
- 무료
- 기관 내 무료
- 유료
-
-
Kim, Hee-Jin,Lee, Jae-Seong,Hagiwara, Atsushi Elsevier 2018 Aquaculture Vol.497 No.-
<P><B>Abstract</B></P> <P>We review a recent progress of photophysiological studies in the rotifer <I>Brachionus plicatilis</I> species complex. The rotifers have a light sensor i.e., eyespot inducing phototactic behavior. For the rotifer <I>B. plicatilis</I> sp. complex, the eyespot efficiently absorbs the light wavelength ranging from 450 to 550 nm. The function of eyespot is affected by diet species from 30-day batch cultures fed by either microalgae <I>Nannochloropsis oculata</I> or baker's yeast <I>Saccharomyces cerevisiae</I>. By feeding baker's yeast, rotifer eyespot gradually lost its function: area (5.5 times) and absorbance (2.2 times) decrease compared to those fed by <I>N. oculata</I>. Phototactic behavior and reproductive characteristics of the rotifer <I>B. plicatilis</I> sp. complex varied with different light wavelengths and intensities. The rotifers show light wavelength dependent phototaxis associated with the reception of an eyespot. For the phototactic behavior in horizontal level, light intensity is also a significant factor to regulate phototaxis. The rotifers show strong positive phototaxis under blue (peaks at 470 nm), green (525 nm), and white (460 and 570 nm) lights at 0.5 W/m<SUP>2</SUP>. Rotifer reproduction is also affected by light wavelength and intensities. Asexual reproduction of rotifers is accelerated by green and red lights at 0.5 W/m<SUP>2</SUP>. On the other hand, active sexual reproduction is observed with blue light at 1.4 W/m<SUP>2</SUP>. Under a certain light condition inducing active phototactic behavior, the rotifers show continuous swimming movement without attaching to substrates. The different behaviors associated with light conditions affect the reproductive characteristics of rotifers. The regulation of live food distribution is significant for feeding efficiency of fish larvae. The efficient feeding promotes larval growth and survival: hence it is a significant factor for successful larviculture. Fish larvae also show different phototactic behavior related to light wavelengths and intensities. Therefore, the distributions of fish larvae under the applied light conditions should be considered.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Rotifer eyespot efficiently absorbs light wavelength from 450 to 550 nm. </LI> <LI> Phototactic behaviors of rotifers are affected by light wavelength and intensity. </LI> <LI> Light wavelength and intensity affect population growth of rotifers. </LI> </UL> </P>
-
Han, Jeonghoon,Park, Jun Chul,Hagiwara, Atsushi,Park, Heum Gi,Lee, Jae-Seong Elsevier 2019 Comparative biochemistry and physiology. Part D, G Vol.29 No.-
<P><B>Abstract</B></P> <P>Cytochrome P450s (CYPs) are a large gene superfamily that are found in all living organisms. CYPs have a key role in detoxification of xenobiotics and endogenous chemicals. Although aquatic invertebrate CYPs and their detoxification mechanisms have been reported, little is known about interspecific comparison of CYPs and their detoxification mechanism in the rotifer <I>Brachionus</I> spp. The aim of this study was to identify the entire <I>CYP</I>s in the rotifer <I>Brachionus rotundiformis</I> (<I>B</I>. <I>rotundiformis</I>) and compare <I>B</I>. <I>rotundiformis</I>-CYPs to the previously reported CYPs in other model <I>Brachionus</I> spp. (<I>B. koreanus</I>, <I>B. plicatilis</I>, and <I>B. calyciflorus</I>). To validate the model, the rotifer, specifically <I>Brachionus rotundiformis</I> was exposed to various concentrations of B[α]P, which is widely used PAH xenobiotic, and analyzed gene expression in response to B[α]P. Here, in silico analysis results showed the total of 26 <I>CYP</I>s from the rotifer <I>B. rotundiformis</I>. Based on the phylogenetic analysis, the 26 <I>B</I>. <I>rotundiformis</I>-CYPs were separated into five different clans: 2, 3, 4, mitochondrial, and 46 clans in comparison to three rotifers species, <I>B. koreanus</I>, <I>B. plicatilis</I>, and <I>B. calyciflorus</I>. To understand the detoxification mechanisms of 26 <I>B</I>. <I>rotundiformis</I>-CYPs, we investigated transcriptional expression of 26 <I>CYP</I>s and found that five <I>CYP</I>s (<I>CYP3045A2</I>, <I>CYP3045B4</I>, <I>CYP3045C10</I>, <I>CYP3049A5</I>, and <I>CYP3049E8</I>) were significantly increased (<I>P</I> < 0.05) in response to 10 and 100 μg B[α]P. In addition, we identified the aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) and observed slight up-regulation of <I>B</I>. <I>rotundiformis</I>-<I>AhR</I> and -<I>ARNT</I>, indicating that these CYPs are likely associated with detoxification mechanism and could be used as potential molecular biomarkers of B[α]P in <I>B. rotundiformis</I>. Overall, this study will be helpful for expanding our knowledge of invertebrate CYPs on detoxification mechanisms associated with AhR signaling pathway in rotifers.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
-
Lee, Bo-Young,Lee, Min-Chul,Jeong, Chang-Bum,Kim, Hee-Jin,Hagiwara, Atsushi,Souissi, Sami,Han, Jeonghoon,Lee, Jae-Seong Elsevier 2018 Comparative biochemistry and physiology. Part D, G Vol.28 No.-
<P><B>Abstract</B></P> <P>The calanoid copepod <I>Eurytemora affinis</I> is one of the most abundant estuarine species and is considered to be an ideal candidate species for ecotoxicological research. An RNA-Seq-based transcriptome was developed from whole bodies of this species. Among 142,442 contigs of the <I>de novo</I> assembly by Trinity, 48,480 open reading frame (ORF) contigs were found using TransDecoder. A total of 17,762 genes were identified by BLAST analysis, which covers about 75% of the annotated genes in the <I>E. affinis</I> genome. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that most annotated sequences were related to metabolism pathways, including xenobiotic biodegradation. Using transcriptome data, we identified putative transcripts related to xenobiotic processing genes including phase I enzymes, phase II enzymes, transporters, and transcription factors. To understand the CYP-mediated detoxification metabolism of xenobiotics, we measured the transcriptional levels of 16 CYPs (within full sequences) of <I>E. affinis</I> in response to benzo[α]pyrene (B[α]P). Most <I>Ea-CYP</I> genes were significantly down- and/or up-regulated (<I>P</I> < 0.05) in response to B[α]P, suggesting that <I>Ea-CYP</I> genes are likely involved in detoxification (mainly in biotransformation of xenobiotics) with particular genes, demonstrating significant upregulation or downregulation compared to others, as shown in other copepod model species (<I>e.g. Tigriopus japonicus</I> and <I>Paracyclopina nana</I>). This study will provide insight into the potential role of <I>E. affinis</I> in response to various toxic or xenobiotic chemicals in the marine environment.</P>
-
-
Jeong, Chang-Bum,Lee, Young Hwan,Park, Jun Chul,Kang, Hye-Min,Hagiwara, Atsushi,Lee, Jae-Seong PERGAMON PRESS 2019 COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C Vol.225 No.-
<P><B>Abstract</B></P> <P>Metal pollution is one of the major threats to the aquatic environment due to its high bio-concentrations and toxicity. Although numerous studies have been conducted to understand detoxification and toxicity mechanisms in aquatic invertebrates, most of them were limited in laboratory study. Here, we investigated adverse effects of the contaminated-natural seawater on the marine rotifer <I>Brachionus koreanus</I>. Field seawater was collected from five different sites of Youngil Bay, South Korea where pollution by metals is predicted due to industrial discharges from nearby steel industry complexes. The marine rotifer <I>B. koreanus</I> was exposed to different seawater samples, and we found decreased population growth rates with highly induced transcriptional level of detoxification-related genes. Our finding shows a link between the induction of metal-mediated regulation of detoxification genes in <I>B. koreanus</I> and concentration of heavy metals present in various seawater samples, implying those biomarker genes can be useful to assess the toxicity of metal polluted natural seawaters. Our results are helpful to validate and establish biomarker genes for early risk assessment of metal contamination in the natural sea water.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ICP-MS analysis revealed the presence of nickel, copper, zinc, and lead in Youngil Bay, South Korea. </LI> <LI> Decreased population growth rates were shown in <I>B. koreanus</I> upon seawater exposures. </LI> <LI> Detoxification-related genes were highly induced upon seawater exposures. </LI> <LI> The induction of detoxification genes was correlated with concentration of heavy metals in various seawaters. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
-
Kim, Duck-Hyun,Kim, Hui-Su,Hwang, Dae-Sik,Kim, Hee-Jin,Hagiwara, Atsushi,Lee, Jae-Seong,Jeong, Chang-Bum Academic Press 2017 General and comparative endocrinology Vol.252 No.-
<P><B>Abstract</B></P> <P>Nuclear receptors (NRs) are a large family of transcription factors that are involved in many fundamental biological processes. NRs are considered to have originated from a common ancestor, and are highly conserved throughout the whole animal taxa. Therefore, the genome-wide identification of <I>NR</I> genes in an animal taxon can provide insight into the evolutionary tendencies of NRs. Here, we identified all the <I>NR</I> genes in the monogonont rotifer <I>Brachionus</I> spp., which are considered an ecologically key species due to their abundance and world-wide distribution. The NR family was composed of 40, 32, 29, and 32 genes in the genomes of the rotifers <I>B</I>. <I>calyciflorus</I>, <I>B. koreanus</I>, <I>B. plicatilis</I>, and <I>B. rotundiformis</I>, respectively, which were classified into seven distinct subfamilies. The composition of each subfamily was highly conserved between species, except for <I>NR1O</I> genes, suggesting that they have undergone sporadic evolutionary processes for adaptation to their different environmental pressures. In addition, despite the dynamics of NR evolution, the significance of the conserved endocrine system, particularly for estrogen receptor (ER)-signaling, in rotifers was discussed on the basis of phylogenetic analyses. The results of this study may help provide a better understanding the evolution of NRs, and expand our knowledge of rotifer endocrine systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fourty, 32, 29, and 32 <I>NR</I> genes were identified in the four rotifer <I>Brachionus</I> spp. </LI> <LI> Species-specific evolution of <I>NR1O</I> genes was identified. </LI> <LI> The evolutionary scenario of ER-signaling pathways in <I>Brachionus</I> spp. have speculated on the basis of our phylogenetic analysis. </LI> </UL> </P>
-
Hwang, Dae-Sik,Suga, Koushirou,Sakakura, Yoshitaka,Park, Heum Gi,Hagiwara, Atsushi,Rhee, Jae-Sung,Lee, Jae-Seong Informa UK Ltd. 2014 Mitochondrial DNA Vol.25 No.1
<P>The complete mitochondrial genome was obtained from the assembled genome data sequenced by next generation sequencing (NGS) technology from the monogonont rotifer <I>Brachionus koreanus</I>. The mitochondrial genome of <I>B. koreanus</I> was composed of two circular chromosomes designated as mtDNA-I (10,421 bp) and mtDNA-II (11,923 bp). The gene contents of <I>B. koreanus</I> were identical with previously reported <I>B. plicatilis</I> mitochondrial genomes. However, gene orders of <I>B. koreanus</I> showed one rearrangement between the two species. Of 12 protein-coding genes (<I>PCG</I>s), 3 genes (<I>ATP6, ND1</I>, and <I>ND3</I>) had an incomplete stop codon. The A + T base composition of <I>B. koreanus</I> mitochondrial genome was high (68.81%). They also showed anti-G bias (12.03% and 10.97%) on the second and third position of <I>PCG</I>s as well as slight anti-C bias (15.96% and 14.31%) on the first and third position of <I>PCG</I>s.</P>
-
-
Kang, Hye-Min,Lee, Jin-Sol,Kim, Min-Sub,Lee, Young Hwan,Jung, Jee-Hyun,Hagiwara, Atsushi,Zhou, Bingsheng,Lee, Jae-Seong,Jeong, Chang-Bum Elsevier 2018 Aquatic toxicology Vol.201 No.-
<P><B>Abstract</B></P> <P>Autophagy originated from the common ancestor of all life forms, and its function is highly conserved from yeast to humans. Autophagy plays a key role in various fundamental biological processes including defense, and has developed through serial interactions of multiple gene sets referred to as autophagy-related (<I>Atg</I>) genes. Despite their significance in metazoan life and evolution, few studies have been conducted to identify these genes in aquatic invertebrates. In this study, we identified whole <I>Atg</I> genes in four <I>Brachionus</I> rotifer spp., namely <I>B. calyciflorus</I>, <I>B. koreanus</I>, <I>B. plicatilis</I>, and <I>B. rotundiformis</I>, through searches of their entire genomes; and we annotated them according to the yeast nomenclature. Twenty-four genes orthologous to yeast genes were present in all of the <I>Brachionus</I> spp. while three additional gene duplicates were identified in the genome of <I>B. koreanus</I>, indicating that these genes had diversified during the speciation. Also, their transcriptional responses to cadmium exposure indicated regulation by cadmium-induced oxidative-stress–related signaling pathways. This study provides valuable information on 99 conserved <I>Atg</I> genes involved in autophagosome formation in <I>Brachionus</I> spp., with transcriptional modulation in response to cadmium, in the context of the role of autophagy in the damage response.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The entire 99 <I>Atg genes</I> in four <I>Brachionus</I> spp. were identified. </LI> <LI> Twenty-four genes orthologous to yeast genes were present in rotifers. </LI> <LI> Three additional duplicated <I>Atg genes</I> were identified in <I>B. koreanus</I>. </LI> <LI> The transcriptional responses of <I>Atg genes</I> were shown in response to cadmium exposure. </LI> </UL> </P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
