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Koji Akasaka - One of the best experts on this subject based on the ideXlab platform.
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Ocean acidification reduces biomineralization-related gene expression in the sea urchin, Hemicentrotus pulcherrimus
Marine Biology, 2012Co-Authors: Haruko Kurihara, Daisuke Kurokawa, Yoshiki Takano, Koji AkasakaAbstract:Although recent studies have demonstrated that calcification in a wide range of marine organisms is profoundly affected by CO2-induced ocean acidification, the mechanism of this phenomenon is still unclear. To clarify the effects of ocean acidification on the calcification process at the molecular level, we evaluated the expression of three biomineralization-related genes in the sea urchin Hemicentrotus pulcherrimus exposed under control, 1,000, and 2,000 ppm CO2 from egg to pluteus larval stage. We found that the expression of the gene msp130, which is proposed to transport Ca2+ to the calcification site, is suppressed by increased CO2 at pluteus larval stage. Meanwhile, expression of the spicule protein matrix genes SM30 and SM50 was apparently not affected. The results suggest that the combined effects of ocean acidification on the expression of skeletogenesis-related genes as well as the change in seawater carbonate chemistry affect the biomineralization ability of sea urchins.
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Sea urchin arylsulfatase, an extracellular matrix component, is involved in gastrulation during embryogenesis
Development Genes and Evolution, 2009Co-Authors: Keiko Mitsunaga-nakatsubo, Yoshihiro Akimoto, Hayato Kawakami, Koji AkasakaAbstract:Arylsulfatases (Arses) have been regarded as lysosomal enzymes because of their hydrolytic activities on synthetic aromatic substrates and their lysosomal localization of their enzymatic activities. Using sea urchin embryos, we previously demonstrated that the bulk of Hemicentrotus Ars (HpArs) does not exhibit enzyme activity and is located on the apical surface of the epithelial cells co-localizing with sulfated polysaccharides. Here we show that HpArs strongly binds to sulfated polysaccharides and that repression of the synthesis by HpArs -morpholino results in retardation of gastrulation in the sea urchin embryo. Accumulation of HpArs protein and sulfated polysaccharides on the apical surface of the epithelial cells in sea urchin larvae is repressed by treatment with β-aminopropionitrile (BAPN), suggesting that deposition of HpArs and sulfated polysaccharides is dependent on the crosslinking of proteins such as collagen-like molecules. We suggest that HpArs functions by binding to components of the extracellular matrix.
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Developmental expression of HpNanos, the Hemicentrotus pulcherrimus homologue of nanos
Gene expression patterns : GEP, 2006Co-Authors: Takayoshi Fujii, Keiko Mitsunaga-nakatsubo, Koji Akasaka, Naoaki Sakamoto, Ikuya Saito, Hiroka Iida, Takashi YamamotoAbstract:The Hemicentrotus pulcherrimus homologue of nanos (HpNanos), that encodes a protein containing two CCHC zinc finger motifs, was isolated from a gastrula cDNA library. The accumulation of HpNanos mRNA during embryonic development and the spatial expression pattern are reported. Developmental northern blot analysis revealed that HpNanos mRNA markedly accumulated during the blastula stages, and then decreased in abundance at the mesenchyme blastula stage. The second phase of HpNanos mRNA expression occurred during gastrulation, after which the expression returned to a low level. Whole-mount in situ hybridization showed that the HpNanos was exclusively expressed in four to six small micromere-descendant cells at the blastula stage. The expression of HpNanos was restricted to the coelomic pouch, which gives rise to the mesoderm of the ventral surface of the adult rudiment, at the prism stage. These results suggest that HpNanos expression will be instrumental for future analyses of the function of small micromere-descendant cells and of the origin of germ cells during sea urchin development.
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Structure, regulation, and function of micro1 in the sea urchin Hemicentrotus pulcherrimus
Development Genes and Evolution, 2004Co-Authors: Yukiko Nishimura, Koji Akasaka, Atsuko Yamazaki, Tokiharu Sato, Yasuhiro Morita, Masaaki YamaguchiAbstract:The animal-vegetal axis of sea urchin embryos is morphologically apparent at the 16-cell stage, when the mesomeres, macromeres, and micromeres align along it. At this stage, the micromere is the only autonomously specified blastomere that functions as a signaling center. We used a subtraction PCR survey to identify the homeobox gene micro1 as a micromere-specific gene. The micro1 gene is a representative of a novel family of paired-like class homeobox genes, along with PlHbox12 from Paracentrotus lividus and pmar1 from Strongylocentrotus purpuratus . In the present study, we showed that micro1 is a multicopy gene with six or more polymorphic loci, at least three of which are clustered in a 30-kb region of the genome. The micro1 gene is transiently expressed during early cleavage stages in the micromere. Recently, nuclear β-catenin was shown to be essential for the specification of vegetal cell fates, including micromeres, and the temporal and spatial coincidence of micro1 expression with the nuclear entry of β-catenin is highly suggestive. We demonstrated that micro1 is a direct target of β-catenin. In addition, we showed that micro1 is necessary and sufficient for micromere specification. These observations on the structure, regulation, and function of micro1 lead to the conclusion that micro1 and pmar1 (and potentially PlHbox12 ) are orthologous.
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brachyury homolog hpta is involved in the formation of archenteron and secondary mesenchyme cell differentiation in the sea urchin embryo
Zoology, 2001Co-Authors: Keiko Mitsunaganakatsubo, Hiraku Shimada, Yoshito Harada, Koji AkasakaAbstract:Summary Sea urchin Brachyury homolog ( HpTa ) is expressed exclusively in the vegetal plate and secondary mesenchyme cells in the embryos of sea urchin Hemicentrotus pulcherrimus . In order to gain insights into the role of HpTa during sea urchin development, we designed experiments to perturb the embryo by inducing ectopic overexpression of HpTa by injecting fertilized eggs with HpTa mRNA. The overexpression of HpTa resulted in suppression of the formation of vegetal plate and secondary mesenchyme cells. We assume that the interaction of HpTa with unknown factors is required for the activation of the HpTa target genes, and that the excess amount of HpTa proteins produced from injected HpTa mRNA depletes the co-factors. In consequence, the target genes of HpTa would be repressed by the overexpression of HpTa . We suggest that HpTa is involved in the formation of the vegetal plate and the differentiation of secondary mesenchyme cells.
Hiraku Shimada - One of the best experts on this subject based on the ideXlab platform.
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brachyury homolog hpta is involved in the formation of archenteron and secondary mesenchyme cell differentiation in the sea urchin embryo
Zoology, 2001Co-Authors: Keiko Mitsunaganakatsubo, Hiraku Shimada, Yoshito Harada, Koji AkasakaAbstract:Summary Sea urchin Brachyury homolog ( HpTa ) is expressed exclusively in the vegetal plate and secondary mesenchyme cells in the embryos of sea urchin Hemicentrotus pulcherrimus . In order to gain insights into the role of HpTa during sea urchin development, we designed experiments to perturb the embryo by inducing ectopic overexpression of HpTa by injecting fertilized eggs with HpTa mRNA. The overexpression of HpTa resulted in suppression of the formation of vegetal plate and secondary mesenchyme cells. We assume that the interaction of HpTa with unknown factors is required for the activation of the HpTa target genes, and that the excess amount of HpTa proteins produced from injected HpTa mRNA depletes the co-factors. In consequence, the target genes of HpTa would be repressed by the overexpression of HpTa . We suggest that HpTa is involved in the formation of the vegetal plate and the differentiation of secondary mesenchyme cells.
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cloning of cyclin e cdna of the sea urchin Hemicentrotus pulcherrimus
Zoological Science, 1997Co-Authors: Daisuke Kurokawa, Koji Akasaka, Keiko Mitsunaganakatsubo, Hiraku ShimadaAbstract:Abstract cDNA encoding maternal cyclin E (HpCycE) has been cloned from the oocyte cDNA library of the sea urchin, Hernicentrotus pulcherrimus, by differential screening with a cDNA probe covering the total poly(A)+ RNAs of 16 cell-stage embryos and gastrulae. In this communication we describe similarity of amino acid sequences between HpCycE and those of cyclin E from other organisms and maternal origin of HpCycE. The amino acid sequence deduced from the nucleotide sequence of HpCycE cDNA is highly similar to those of human, rat, chicken, Xenopus, zebrafish and Drosophila, while its similarity to other cyclins is much lower. A gene for HpCycE exists as a single copy in the genome of H. pulcherrimus. Northern blotting revealed that the mRNA for HpCycE is maintained at a high level up to the morula stage and thereafter declines.
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a triplex dna structure of the polypyrimidine polypurine stretch in the 5 flanking region of the sea urchin arylsulfatase gene
Zoological Science, 1996Co-Authors: Naoaki Sakamoto, Koji Akasaka, Takashi Yamamoto, Hiraku ShimadaAbstract:Previously we reported that a long (522 bp) polypyrimidine: polypurine stretch in the 5' flanking region of the arylsulfatase gene of the sea urchin, Hemicentrotus pulcherrimus, took an unusual, perhaps triplex, DNA structure, when subjected to an acidic pH (pH 5) (Yamamoto et al., 1994). In the present study we have isolated a polypyrimidine: polypurine containing fragment from the arylsulfatase gene and surveyed the sensitivities of the polypyrimidine: polypurine stretch to base modification by diethylpyrocarbonate and osmium tetroxide under various levels of negative supercoiling. Based on the sensitivity of highly negatively supercoiled DNA to these base-modifying reagents, we conclude that, when highly negatively supercoiled, the polypyrimidine: polypurine stretch can take a triplex DNA structure even at a neutral pH and under physiological ionic strength in the presence of Mg2+.
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corrected structure of the 5 flanking region of arylsulfatase gene of the sea urchin Hemicentrotus pulcherrimus 5 flanking sequence sea urchin arylsulfatase gene g string
Development Growth & Differentiation, 1994Co-Authors: Koji Akasaka, Naoaki Sakamoto, Takashi Yamamoto, Junji Morokuma, Nobuhisa Fujikawa, Kazuko Takata, Sachiko Eguchi, Hiraku ShimadaAbstract:The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning. In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
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Corrected Structure of the 5' Flanking Region of Arylsulfatase Gene of the Sea Urchin, Hemicentrotus pulcherrimus. (5' flanking sequence/sea urchin/arylsulfatase gene/G-string)
Development Growth and Differentiation, 1994Co-Authors: Koji Akasaka, Naoaki Sakamoto, Takashi Yamamoto, Junji Morokuma, Nobuhisa Fujikawa, Kazuko Takata, Sachiko Eguchi, Hiraku ShimadaAbstract:The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning. In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
Takashi Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Usage of the Sea Urchin Hemicentrotus pulcherrimus Database, HpBase.
Methods in molecular biology (Clifton N.J.), 2020Co-Authors: Sonoko Kinjo, Takashi Yamamoto, Masato Kiyomoto, Kazuho Ikeo, Shunsuke YaguchiAbstract:HpBase ( http://cell-innovation.nig.ac.jp/Hpul/ ) is a database that provides genome and transcriptome resources of the sea urchin Hemicentrotus pulcherrimus. In addition to downloading the bulk data, several analysis tools for resource use are available: gene search, homology search, and genome browsing. HpBase also discloses the protocols for biological experiments using H. pulcherrimus that have been accumulated so far. Therefore, HpBase can assist efficient use of genome resources for researchers from various fields-evolutionary, developmental, and cell biology. In this chapter we present an overview and usage of tools in HpBase.
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hpbase a genome database of a sea urchin Hemicentrotus pulcherrimus
Development Growth & Differentiation, 2018Co-Authors: Sonoko Kinjo, Takashi Yamamoto, Masato Kiyomoto, Kazuho Ikeo, Shunsuke YaguchiAbstract:To understand the mystery of life, it is important to accumulate genomic information for various organisms because the whole genome encodes the commands for all the genes. Since the genome of Strongylocentrotus purpratus was sequenced in 2006 as the first sequenced genome in echinoderms, the genomic resources of other North American sea urchins have gradually been accumulated, but no sea urchin genomes are available in other areas, where many scientists have used the local species and reported important results. In this manuscript, we report a draft genome of the sea urchin Hemincentrotus pulcherrimus because this species has a long history as the target of developmental and cell biology in East Asia. The genome of H. pulcherrimus was assembled into 16,251 scaffold sequences with an N50 length of 143 kbp, and approximately 25,000 genes were identified in the genome. The size of the genome and the sequencing coverage were estimated to be approximately 800 Mbp and 100×, respectively. To provide these data and information of annotation, we constructed a database, HpBase (http://cell-innovation.nig.ac.jp/Hpul/). In HpBase, gene searches, genome browsing, and blast searches are available. In addition, HpBase includes the "recipes" for experiments from each lab using H. pulcherrimus. These recipes will continue to be updated according to the circumstances of individual scientists and can be powerful tools for experimental biologists and for the community. HpBase is a suitable dataset for evolutionary, developmental, and cell biologists to compare H. pulcherrimus genomic information with that of other species and to isolate gene information.
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targeted mutagenesis in the sea urchin embryo using zinc finger nucleases
Genes to Cells, 2010Co-Authors: Hiroshi Ochiai, Masatoshi Nishikawa, Naoaki Sakamoto, Kazumasa Fujita, Tatsuo Shibata, Kenichi T Suzuki, Takashi YamamotoAbstract:We showed that engineered zinc-finger nucleases (ZFNs), which consist of a zinc-finger DNA-binding array and a nuclease domain of the restriction enzyme FokI, can introduce mutations at a specific genomic site in the sea urchin embryo. Using bacterial one-hybrid screening with zinc-finger randomized libraries and a single-strand annealing assay in cultured cells, ZFNs targeting the sea urchin Hemicentrotus pulcherrimus homologue of HesC (HpHesC) were efficiently selected. Consistent with the phenotype observed in embryos injected with an antisense morpholino oligonucleotide against HpHesC, an increase in the primary mesenchyme cell population was observed in embryos injected with a pair of HpHesC ZFN mRNAs. In addition, sequence analysis of the mutations showed that deletions and insertions occurred at the HpHesC target site in the embryos injected with the HpHesC ZFN mRNAs. These results suggest that targeted gene disruption using ZFNs is feasible for the sea urchin embryo.
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Dicer is required for the normal development of sea urchin, Hemicentrotus pulcherrimus.
Zoological science, 2010Co-Authors: Yuka Okamitsu, Takashi Yamamoto, Hiroshi Ochiai, Takayoshi Fujii, Naoaki SakamotoAbstract:MicroRNAs are single-stranded RNA molecules with a length of 19–25 nucleotides, which play roles in various biological phenomena, including development, differentiation, apoptosis, by regulating target gene expression. Although the presence of microRNA molecules in sea urchin and the expression of genes involved in microRNA biogenesis during sea urchin development have been reported recently, the function of microRNA in sea urchin development remains to be elucidated. In this study, to understand the function of microRNA in the early development of sea urchin, we focused on Dicer, an essential enzyme for biosynthesis of mature microRNA. We determined the nucleotide sequence of cDNA for a Dicer homolog in the sea urchin, Hemicentrotus pulcherrimus, HpDcr, and found that functional domains of Dicer proteins are conserved in HpDcr. Analyses of its pattern of expression showed that HpDcr mRNA is expressed in embryos at all developmental stages analyzed, and seems to distribute asymmetrically at the morula and later stages. Knockdown of HpDcr resulted in anomalous morphogenesis, such as impairment of gastrulation and skeletogenesis at the mesenchyme blastula stage and later stages, and alteration of mRNA levels of cell type-specific genes. Thus, HpDcr plays important roles in morphogenesis in sea urchin embryos, suggesting that miRNA could be involved in the early development of sea urchin by regulating target gene expression.
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Developmental expression of HpNanos, the Hemicentrotus pulcherrimus homologue of nanos
Gene expression patterns : GEP, 2006Co-Authors: Takayoshi Fujii, Keiko Mitsunaga-nakatsubo, Koji Akasaka, Naoaki Sakamoto, Ikuya Saito, Hiroka Iida, Takashi YamamotoAbstract:The Hemicentrotus pulcherrimus homologue of nanos (HpNanos), that encodes a protein containing two CCHC zinc finger motifs, was isolated from a gastrula cDNA library. The accumulation of HpNanos mRNA during embryonic development and the spatial expression pattern are reported. Developmental northern blot analysis revealed that HpNanos mRNA markedly accumulated during the blastula stages, and then decreased in abundance at the mesenchyme blastula stage. The second phase of HpNanos mRNA expression occurred during gastrulation, after which the expression returned to a low level. Whole-mount in situ hybridization showed that the HpNanos was exclusively expressed in four to six small micromere-descendant cells at the blastula stage. The expression of HpNanos was restricted to the coelomic pouch, which gives rise to the mesoderm of the ventral surface of the adult rudiment, at the prism stage. These results suggest that HpNanos expression will be instrumental for future analyses of the function of small micromere-descendant cells and of the origin of germ cells during sea urchin development.
Naoaki Sakamoto - One of the best experts on this subject based on the ideXlab platform.
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targeted mutagenesis in the sea urchin embryo using zinc finger nucleases
Genes to Cells, 2010Co-Authors: Hiroshi Ochiai, Masatoshi Nishikawa, Naoaki Sakamoto, Kazumasa Fujita, Tatsuo Shibata, Kenichi T Suzuki, Takashi YamamotoAbstract:We showed that engineered zinc-finger nucleases (ZFNs), which consist of a zinc-finger DNA-binding array and a nuclease domain of the restriction enzyme FokI, can introduce mutations at a specific genomic site in the sea urchin embryo. Using bacterial one-hybrid screening with zinc-finger randomized libraries and a single-strand annealing assay in cultured cells, ZFNs targeting the sea urchin Hemicentrotus pulcherrimus homologue of HesC (HpHesC) were efficiently selected. Consistent with the phenotype observed in embryos injected with an antisense morpholino oligonucleotide against HpHesC, an increase in the primary mesenchyme cell population was observed in embryos injected with a pair of HpHesC ZFN mRNAs. In addition, sequence analysis of the mutations showed that deletions and insertions occurred at the HpHesC target site in the embryos injected with the HpHesC ZFN mRNAs. These results suggest that targeted gene disruption using ZFNs is feasible for the sea urchin embryo.
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Dicer is required for the normal development of sea urchin, Hemicentrotus pulcherrimus.
Zoological science, 2010Co-Authors: Yuka Okamitsu, Takashi Yamamoto, Hiroshi Ochiai, Takayoshi Fujii, Naoaki SakamotoAbstract:MicroRNAs are single-stranded RNA molecules with a length of 19–25 nucleotides, which play roles in various biological phenomena, including development, differentiation, apoptosis, by regulating target gene expression. Although the presence of microRNA molecules in sea urchin and the expression of genes involved in microRNA biogenesis during sea urchin development have been reported recently, the function of microRNA in sea urchin development remains to be elucidated. In this study, to understand the function of microRNA in the early development of sea urchin, we focused on Dicer, an essential enzyme for biosynthesis of mature microRNA. We determined the nucleotide sequence of cDNA for a Dicer homolog in the sea urchin, Hemicentrotus pulcherrimus, HpDcr, and found that functional domains of Dicer proteins are conserved in HpDcr. Analyses of its pattern of expression showed that HpDcr mRNA is expressed in embryos at all developmental stages analyzed, and seems to distribute asymmetrically at the morula and later stages. Knockdown of HpDcr resulted in anomalous morphogenesis, such as impairment of gastrulation and skeletogenesis at the mesenchyme blastula stage and later stages, and alteration of mRNA levels of cell type-specific genes. Thus, HpDcr plays important roles in morphogenesis in sea urchin embryos, suggesting that miRNA could be involved in the early development of sea urchin by regulating target gene expression.
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Developmental expression of HpNanos, the Hemicentrotus pulcherrimus homologue of nanos
Gene expression patterns : GEP, 2006Co-Authors: Takayoshi Fujii, Keiko Mitsunaga-nakatsubo, Koji Akasaka, Naoaki Sakamoto, Ikuya Saito, Hiroka Iida, Takashi YamamotoAbstract:The Hemicentrotus pulcherrimus homologue of nanos (HpNanos), that encodes a protein containing two CCHC zinc finger motifs, was isolated from a gastrula cDNA library. The accumulation of HpNanos mRNA during embryonic development and the spatial expression pattern are reported. Developmental northern blot analysis revealed that HpNanos mRNA markedly accumulated during the blastula stages, and then decreased in abundance at the mesenchyme blastula stage. The second phase of HpNanos mRNA expression occurred during gastrulation, after which the expression returned to a low level. Whole-mount in situ hybridization showed that the HpNanos was exclusively expressed in four to six small micromere-descendant cells at the blastula stage. The expression of HpNanos was restricted to the coelomic pouch, which gives rise to the mesoderm of the ventral surface of the adult rudiment, at the prism stage. These results suggest that HpNanos expression will be instrumental for future analyses of the function of small micromere-descendant cells and of the origin of germ cells during sea urchin development.
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a triplex dna structure of the polypyrimidine polypurine stretch in the 5 flanking region of the sea urchin arylsulfatase gene
Zoological Science, 1996Co-Authors: Naoaki Sakamoto, Koji Akasaka, Takashi Yamamoto, Hiraku ShimadaAbstract:Previously we reported that a long (522 bp) polypyrimidine: polypurine stretch in the 5' flanking region of the arylsulfatase gene of the sea urchin, Hemicentrotus pulcherrimus, took an unusual, perhaps triplex, DNA structure, when subjected to an acidic pH (pH 5) (Yamamoto et al., 1994). In the present study we have isolated a polypyrimidine: polypurine containing fragment from the arylsulfatase gene and surveyed the sensitivities of the polypyrimidine: polypurine stretch to base modification by diethylpyrocarbonate and osmium tetroxide under various levels of negative supercoiling. Based on the sensitivity of highly negatively supercoiled DNA to these base-modifying reagents, we conclude that, when highly negatively supercoiled, the polypyrimidine: polypurine stretch can take a triplex DNA structure even at a neutral pH and under physiological ionic strength in the presence of Mg2+.
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corrected structure of the 5 flanking region of arylsulfatase gene of the sea urchin Hemicentrotus pulcherrimus 5 flanking sequence sea urchin arylsulfatase gene g string
Development Growth & Differentiation, 1994Co-Authors: Koji Akasaka, Naoaki Sakamoto, Takashi Yamamoto, Junji Morokuma, Nobuhisa Fujikawa, Kazuko Takata, Sachiko Eguchi, Hiraku ShimadaAbstract:The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning. In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
Sachiko Eguchi - One of the best experts on this subject based on the ideXlab platform.
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corrected structure of the 5 flanking region of arylsulfatase gene of the sea urchin Hemicentrotus pulcherrimus 5 flanking sequence sea urchin arylsulfatase gene g string
Development Growth & Differentiation, 1994Co-Authors: Koji Akasaka, Naoaki Sakamoto, Takashi Yamamoto, Junji Morokuma, Nobuhisa Fujikawa, Kazuko Takata, Sachiko Eguchi, Hiraku ShimadaAbstract:The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning. In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
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Corrected Structure of the 5' Flanking Region of Arylsulfatase Gene of the Sea Urchin, Hemicentrotus pulcherrimus. (5' flanking sequence/sea urchin/arylsulfatase gene/G-string)
Development Growth and Differentiation, 1994Co-Authors: Koji Akasaka, Naoaki Sakamoto, Takashi Yamamoto, Junji Morokuma, Nobuhisa Fujikawa, Kazuko Takata, Sachiko Eguchi, Hiraku ShimadaAbstract:The nucleotide sequence of the 5′ flanking region of the arylsulfatase (Ars) gene of the sea urchin, Hemicentrotus pulcherrimus, is extensively corrected. The one previously reported from our laboratory (ref. 7, Develop, Growth & Differ., 34, 719–729, 1992) contains many sequencing errors and should be replaced with that presented here. Correction includes the addition of a 294 nucleotide (nt) sequence between −728 and −1,021. In the previous sequencing, this fragment was missed by overlooking one Hindlll site during subcloning. In addition to a cluster of direct repeats between −2,592 and −3,440, an inverted repeat is detected between −217 and −476. A possible role of the inverted repeat in the regulation of transcription of the Ars gene is discussed.
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cis acting elements for proper ontogenic expression of arylsulfatase gene of sea urchin embryo
Development Growth & Differentiation, 1992Co-Authors: K. Yamada, Koji Akasaka, Takashi Yamamoto, Sachiko Eguchi, Hiraku ShimadaAbstract:To define the cis-acting regulatory elements required for proper ontogenic expression of the Arylsulfatase gene in the sea urchin (Hemicentrotus pulcherrimus) embryo, we have constructed the fusion genes composed of bacterial CAT gene and various regions from the 5′ flanking sequence of the Ars gene, injected them into unfertilized sea urchin eggs and monitored their expression during development. A wild type construct containing the 5′ flanking region of the Ars gene spanning from —2 to —3160 was expressed under proper temporal regulation following injection into unfertilized eggs. By deletion analysis the transcriptional enhancers were localized between —1280 and —2680 of the Ars gene. In addition, sequences acting as a negative regulator as well as a minimal promoter for expression of the Ars gene were detected by internal deletion analysis.