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21.
Faviel A. López-Romero Claudia Klimpfinger Sho Tanaka Jürgen Kriwet 《Journal of fish biology》2020,97(1):212-224
Chlamydoselachus anguineus, Garman 1884, commonly called the frilled shark, is a deep-sea shark species occurring up to depths of 1300 m. It is assumed to represent an ancient morphotype of sharks (e.g., terminal mouth opening, more than five gill slits) and thus is often considered to represent plesiomorphic traits for sharks. Therefore, its early ontogenetic developmental traits are important for understanding the evolution of its particular phenotype. Here, we established six stages for prenatal embryos and used linear measurements and geometric morphometrics to analyse changes in shape and size as well as their timing during different embryonic stages. Our results show a change in head shape and a relocation of the mouth opening at a late stage of development. We also detected a negative allometric growth of the head and especially the eye compared to the rest of the body and a sexual dimorphism in total body length, which differs from the known data for adults. A multivariate analysis of covariance shows a significant interaction of shape related to the logarithm of centroid size and developmental stage. Geometric morphometrics results indicate that the head shape changes as a covariate of body size while not accounting for differences between sexes. The growth pattern of stages 32 and 33 indicates a shift in head shape, thus highlighting the moment in development when the jaws start to elongate anteriorly to finally achieve the adult condition of terminal mouth opening rather than retaining the early embryonic subterminal position as is typical for sharks. Thus, the antero-terminal mouth opening of the frilled shark has to be considered a derived feature. 相似文献
22.
Masanori Tachikawa Kazunari Suzuki Kaoru Iguchi Tomoo Miyazaki 《Molecular simulation》2013,39(3-6):291-298
Abstract The weak interaction energy of H2 dimer is studied by double symmetry-adapted perturbation theory (SAPT) within second-order of intermolecular and intramonomer perturbation for molecular simulations. The assumed orientations of H2 dimer are linear, parallel, T type and X type. Among four orientations T orientation is the most stable, while linear orientation is the most repulsive. The second-order dispersion energy E disp (2) is the most attractive contribution in all orientations. The interaction energy has the anisotropy, so we expressed our total interaction energy by the spherical expansion to compare with the experimental value. The isotropic interaction energy is about 85% of the experimental value. 相似文献
23.
Shengchen Tao Daiju Yamazaki Shinji Komazaki Chengzhu Zhao Tsunaki Iida Sho Kakizawa Yuji Imaizumi Hiroshi Takeshima 《The Journal of biological chemistry》2013,288(22):15581-15589
The TRIC channel subtypes, namely TRIC-A and TRIC-B, are intracellular monovalent cation-specific channels and likely mediate counterion movements to support efficient Ca2+ release from the sarco/endoplasmic reticulum. Vascular smooth muscle cells (VSMCs) contain both TRIC subtypes and two Ca2+ release mechanisms; incidental opening of ryanodine receptors (RyRs) generates local Ca2+ sparks to induce hyperpolarization and relaxation, whereas agonist-induced activation of inositol trisphosphate receptors produces global Ca2+ transients causing contraction. Tric-a knock-out mice develop hypertension due to insufficient RyR-mediated Ca2+ sparks in VSMCs. Here we describe transgenic mice overexpressing TRIC-A channels under the control of a smooth muscle cell-specific promoter. The transgenic mice developed congenital hypotension. In Tric-a-overexpressing VSMCs from the transgenic mice, the resting membrane potential decreased because RyR-mediated Ca2+ sparks were facilitated and cell surface Ca2+-dependent K+ channels were hyperactivated. Under such hyperpolarized conditions, L-type Ca2+ channels were inactivated, and thus, the resting intracellular Ca2+ levels were reduced in Tric-a-overexpressing VSMCs. Moreover, Tric-a overexpression impaired inositol trisphosphate-sensitive stores to diminish agonist-induced Ca2+ signaling in VSMCs. These altered features likely reduced vascular tonus leading to the hypotensive phenotype. Our Tric-a-transgenic mice together with Tric-a knock-out mice indicate that TRIC-A channel density in VSMCs is responsible for controlling basal blood pressure at the whole-animal level. 相似文献
24.
Yoshiya Ikawa Satoshi Touden Sho Katsumata Hiroyuki Furuta 《Bioorganic & medicinal chemistry》2013,21(21):6501-6505
A water-soluble derivative of N-fused porphyrin (NFP) possessing four cationic side-arms (pPyNFP) serves as a unique class of colorimetric/fluorogenic reporters that selectively react with biothiols in aquaous media to afford N-confused porphyrin (NCP) derivatives, while other nucleophilic amino acids were inert under a wide range of pH conditions. Owing to the large difference of the optical properties between NCP and NFP, the transformation enabled selective detection of biothiols in colorimetric/fluorogenic manner, especially in the near-infrared region. To the best our knowledge, this is the first example of porphyrin-based thiol detection systems that use the direct attack of thiol group on the optical reporter. 相似文献
25.
Tadanobu Nakadai Seiichi Nasuno Nobuyoshi Iguchi 《Bioscience, biotechnology, and biochemistry》2013,77(9):1481-1488
Acid carboxypeptidase III from Aspergillus oryzae was purified from the rivanol non-precipitated fraction. The optimum activity of the enzyme occurred at pH 3.0 for carbobenzoxy-l-glutamyl-l-tyrosine. The enzyme was inhibited by diisopropylphosphorofluoridate and SH reagents such as p-chloromercuribenzoate and monoiodoacetate, but not by such metal chelating agents as ethylenediaminetetraacetate, αα′-dipyridyl and o-phenanthroline. The molecular weight of the enzyme was estimated to be about 61,000. The enzyme hydrolyzed the peptides that possess masked or bulky N-terminal. 相似文献
26.
Tadanobu Nakadai Seiichi Nasuno Nobuyoshi Iguchi 《Bioscience, biotechnology, and biochemistry》2013,77(7):1239-1243
To elucidate the mechanism of light-activation of pyruvate PL dikinase in maize leaf, the inactive form was purified to homogeneity from dark-treated leaves using an activation system to locate it. The purification procedure included ammonium sulfate-fractionation followed by conventional chromatography.The homogeneous enzyme after maximal activation had a specific activity comparable to that of the active enzyme obtained from non-dark-treated plants. The enzyme was indistinguishable from the active one in its molecular size and charge and in the amino acid composition of its acid-hydrolysate. 相似文献
27.
Zhongwei Zou Masahiko Ishida Feng Li Tomohiro Kakizaki Sho Suzuki Hiroyasu Kitashiba Takeshi Nishio 《PloS one》2013,8(1)
SNP markers for QTL analysis of 4-MTB-GSL contents in radish roots were developed by determining nucleotide sequences of bulked PCR products using a next-generation sequencer. DNA fragments were amplified from two radish lines by multiplex PCR with six primer pairs, and those amplified by 2,880 primer pairs were mixed and sequenced. By assembling sequence data, 1,953 SNPs in 750 DNA fragments, 437 of which have been previously mapped in a linkage map, were identified. A linkage map of nine linkage groups was constructed with 188 markers, and five QTLs were detected in two F2 populations, three of them accounting for more than 50% of the total phenotypic variance being repeatedly detected. In the identified QTL regions, nine SNP markers were newly produced. By synteny analysis of the QTLs regions with Arabidopsis thaliana and Brassica rapa genome sequences, three candidate genes were selected, i.e., RsMAM3 for production of aliphatic glucosinolates linked to GSL-QTL-4, RsIPMDH1 for leucine biosynthesis showing strong co-expression with glucosinolate biosynthesis genes linked to GSL-QTL-2, and RsBCAT4 for branched-chain amino acid aminotransferase linked to GSL-QTL-1. Nucleotide sequences and expression of these genes suggested their possible function in 4MTB-GSL biosynthesis in radish roots. 相似文献
28.
Tomohiro Iguchi Sho Nambara Takaaki Masuda Hisateru Komatsu Masami Ueda Shinya Kidogami Yushi Ogawa Qingjiang Hu Kuniaki Sato Tomoko Saito Hidenari Hirata Shotaro Sakimura Ryutaro Uchi Naoki Hayashi Shuhei Ito Hidetoshi Eguchi Keishi Sugimachi Yoshihiko Maehara Koshi Mimori 《PloS one》2016,11(11)
miR-146a plays important roles in cancer as it directly targets NUMB, an inhibitor of Notch signaling. miR-146a is reportedly regulated by a G>C polymorphism (SNP; rs2910164). This polymorphism affects various cancers, including colorectal cancer (CRC). However, the clinical significance of miR-146a polymorphism in CRC remains unclear. A total of 59 patients with CRC were divided into 2 groups: a CC/CG genotype (n = 32) and a GG genotype (n = 27), based on the miR-146a polymorphism. cDNA microarray analysis was performed using 59 clinical samples. Significantly enriched gene sets in each genotype were extracted using GSEA. We also investigated the association between miR-146a polymorphism and miR-146a, NUMB expression or migratory response in CRC cell lines. The CC/CG genotype was associated with significantly more synchronous liver metastasis (p = 0.007). A heat map of the two genotypes showed that the expression profiles were clearly stratified. GSEA indicated that Notch signaling and JAK/STAT3 signaling were significantly associated with the CC/CG genotype (p = 0.004 and p = 0.023, respectively). CRC cell lines with the pre-miR-146a/C revealed significantly higher miR-146a expression (p = 0.034) and higher NUMB expression and chemotactic activity. In CRC, miR-146a polymorphism is involved in liver metastasis. Identification of this polymorphism could be useful to identify patients with a high risk of liver metastasis in CRC. 相似文献
29.
Yasunori Sugiyama Sho Yamashita Yuuki Uezato Yukako Senga Syouichi Katayama Naoki Goshima Yasushi Shigeri Noriyuki Sueyoshi Isamu Kameshita 《Analytical biochemistry》2016
To analyze a variety of protein phosphatases, we developed phosphorylated TandeMBP (P-TandeMBP), in which two different mouse myelin basic protein isoforms were fused in tandem, as a protein phosphatase substrate. P-TandeMBP was prepared efficiently in four steps: (1) phosphorylation of TandeMBP by a protein kinase mixture (Ca2+/calmodulin-dependent protein kinase Iδ, casein kinase 1δ, and extracellular signal-regulated kinase 2); (2) precipitation of both P-TandeMBP and protein kinases to remove ATP, Pi, and ADP; (3) acid extraction of P-TandeMBP with HCl to remove protein kinases; and (4) neutralization of the solution that contains P-TandeMBP with Tris. In combination with the malachite green assay, P-TandeMBP can be used to detect protein phosphatase activity without using radioactive materials. Moreover, P-TandeMBP served as an efficient substrate for PPM family phosphatases (PPM1A, PPM1B, PPM1D, PPM1F, PPM1G, PPM1H, PPM1K, and PPM1M) and PPP family phosphatase PP5. Various phosphatase activities were also detected with high sensitivity in gel filtration fractions from mouse brain using P-TandeMBP. These results indicate that P-TandeMBP might be a powerful tool for the detection of protein phosphatase activities. 相似文献
30.