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31.
Underwater observations of two living individuals and an examination of a freshly dead individual of the rare deep-sea fish Triodon macropterus revealed that they usually have the large ventral flap completely uplifted and seamlessly retracted into the abdominal region of the trunk: one individual was collected at a depth of 280 m by hook and line east of Tonaki-jima Island, Ryukyu Islands, and kept in a tank at the Okinawa Churaumi Aquarium for six years; the second living individual was observed by the ROV Hakuyo 2000 at a depth of 275 m east of Ishigaki-jima Island, Ryukyu Islands; and another individual collected at depths of 250?350 m by hook and line off Funchu Point, Yoron-jima Island (27°00.15’N, 128°26.06’E), Ryukyu Islands, provided an opportunity to demonstrate that the ventral flap could be manually uplifted by rotating the pelvis. When the ventral flap was uplifted in all of these specimens, whether naturally or manually, there were no scaleless linear bands or streaks and gaps evident in the skin between the retracted ventral flap and the abdominal region. The fine structure of the scales of the body and the ventral flap was observed by light microscopy, scanning electron microscopy, and X-ray CT scanning. The scales of the ventral flap are arranged in rows radiating from the antero-dorsal part of the ventral flap where the anterior part of the pelvis articulates with and rotates around the pectoral girdles. The orientation of the rows on the ventral flap changes from a posterior direction dorsally to a posteroventral direction more ventrally. A ridge with many sharp serrations is raised and bent from the edge of each scale on the body and ventral flap. The raised ridges on the lower scales on the ventral flap become packed together with the upper scales to form a seamless surface when the ventral flap is uplifted into the abdominal region. 相似文献
32.
Taniguchi E Toyoshima-Morimoto F Nishida E 《The Journal of biological chemistry》2002,277(50):48884-48888
Polo-like kinase 1 (Plk1), a mammalian ortholog of Drosophila Polo, is a serine-threonine protein kinase implicated in the regulation of multiple aspects of mitosis. The protein level, activity, and localization of Plk1 change during the cell cycle, and its proper subcellular localization is thought to be crucial for its function. Although localization of Plk1 to the centrosome has been established, nuclear localization or nucleocytoplasmic translocation of Plk1 has not been fully addressed. Here we show that Plk1 accumulates in both the nucleus and the cytoplasm in addition to its localization to the centrosome during S and G(2) phases. Our results identify a conserved region in the kinase domain of Plk1 (residues 134-146) as a functional bipartite nuclear localization signal (NLS) sequence that regulates nuclear translocation of Plk1. The identified NLS is necessary and sufficient for directing nuclear localization of Plk1. This bipartite NLS has an unusually short spacer sequence between two clusters of basic amino acids but is sensitive to RanQ69L, a dominant negative form of Ran, similar to ordinary bipartite NLS. Remarkably, the expression of an NLS-disrupted mutant of Plk1 during S phase was found to arrest the cells in G(2) phase. These results suggest that the bipartite NLS-dependent nuclear localization of Plk1 before mitosis is important for ensuring normal cell cycle progression. 相似文献
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Maino Tahara Yuri Ito Melinda A. Brindley Xuemin Ma Jilan He Songtao Xu Hideo Fukuhara Kouji Sakai Katsuhiro Komase Paul A. Rota Richard K. Plemper Katsumi Maenaka Makoto Takeda 《Journal of virology》2013,87(1):666-675
Effective vaccination programs have dramatically reduced the number of measles-related deaths globally. Although all the available data suggest that measles eradication is biologically feasible, a structural and biochemical basis for the single serotype nature of measles virus (MV) remains to be provided. The hemagglutinin (H) protein, which binds to two discrete proteinaceous receptors, is the major neutralizing target. Monoclonal antibodies (MAbs) recognizing distinct epitopes on the H protein were characterized using recombinant MVs encoding the H gene from different MV genotypes. The effects of various mutations on neutralization by MAbs and virus fitness were also analyzed, identifying the location of five epitopes on the H protein structure. Our data in the present study demonstrated that the H protein of MV possesses at least two conserved effective neutralizing epitopes. One, which is a previously recognized epitope, is located near the receptor-binding site (RBS), and thus MAbs that recognize this epitope blocked the receptor binding of the H protein, whereas the other epitope is located at the position distant from the RBS. Thus, a MAb that recognizes this epitope did not inhibit the receptor binding of the H protein, rather interfered with the hemagglutinin-fusion (H-F) interaction. This epitope was suggested to play a key role for formation of a higher order of an H-F protein oligomeric structure. Our data also identified one nonconserved effective neutralizing epitope. The epitope has been masked by an N-linked sugar modification in some genotype MV strains. These data would contribute to our understanding of the antigenicity of MV and support the global elimination program of measles. 相似文献
35.
DNA ploidy pattern and amplification of ERBB and ERBB2 genes in human gastric carcinomas 总被引:1,自引:0,他引:1
N Oda T Tsujino T Tsuda K Yoshida H Nakayama W Yasui E Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,58(4):273-277
The DNA ploidy pattern and amplification of ERBB and ERBB2 genes were examined in paraffin-embedded tissue from gastric carcinomas using flow cytometry and a slot-blot hybridization technique. The incidence of aneuploidy in well differentiated adenocarcinomas (56%) was significantly higher (p less than 0.05) than that in poorly differentiated adenocarcinomas (21%). The DNA ploidy pattern was not remarkably different between the primary tumors and metastatic deposits in lymph nodes. Of the nine specimens having an aneuploid stem cell line in the primary tumor and/or in metastases, three showed ERBB2 gene amplification and one showed ERBB gene amplification. The incidence of epidermal growth factor (EGF) immunoreactivity in tumor cells showed no difference between diploid and aneuploid tumors. These findings indicate that aneuploidy is frequently associated with amplification of ERBB and ERBB2 genes. 相似文献
36.
Yu Kitadate David J. Jörg Moe Tokue Ayumi Maruyama Rie Ichikawa Soken Tsuchiya Eri Segi-Nishida Toshinori Nakagawa Aya Uchida Chiharu Kimura-Yoshida Seiya Mizuno Fumihiro Sugiyama Takuya Azami Masatsugu Ema Chiyo Noda Satoru Kobayashi Isao Matsuo Yoshiakira Kanai Shosei Yoshida 《Cell Stem Cell》2019,24(1):79-92.e6
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Nishi Y Fujimoto S Sasaki M Mukai E Sato H Sato Y Tahara Y Nakamura Y Inagaki N 《The Biochemical journal》2011,435(2):421-430
In pancreatic β-cells, glucose-induced mitochondrial ATP production plays an important role in insulin secretion. The mitochondrial phosphate carrier PiC is a member of the SLC25 (solute carrier family 25) family and transports Pi from the cytosol into the mitochondrial matrix. Since intramitochondrial Pi is an essential substrate for mitochondrial ATP production by complex V (ATP synthase) and affects the activity of the respiratory chain, Pi transport via PiC may be a rate-limiting step for ATP production. We evaluated the role of PiC in metabolism-secretion coupling in pancreatic β-cells using INS-1 cells manipulated to reduce PiC expression by siRNA (small interfering RNA). Consequent reduction of the PiC protein level decreased glucose (10 mM)-stimulated insulin secretion, the ATP:ADP ratio in the presence of 10 mM glucose and elevation of intracellular calcium concentration in response to 10 mM glucose without affecting the mitochondrial membrane potential (Δψm) in INS-1 cells. In experiments using the mitochondrial fraction of INS-1 cells in the presence of 1 mM succinate, PiC down-regulation decreased ATP production at various Pi concentrations ranging from 0.001 to 10 mM, but did not affect Δψm at 3 mM Pi. In conclusion, the Pi supply to mitochondria via PiC plays a critical role in ATP production and metabolism-secretion coupling in INS-1 cells. 相似文献
39.
Hiroya Miyamoto Eri Katsuyama Yoshiteru Miyauchi Hiroko Hoshi Kana Miyamoto Yuiko Sato Tami Kobayashi Ryotaro Iwasaki Shigeyuki Yoshida Tomoaki Mori Hiroya Kanagawa Atsuhiro Fujie Wu Hao Hideo Morioka Morio Matsumoto Yoshiaki Toyama Takeshi Miyamoto 《The Journal of biological chemistry》2012,287(39):32479-32484
40.
Hidenobu Uchida Eri Ikeuchi Tomohito Yamasaki Takeshi Ohama 《Journal of phycology》2012,48(5):1299-1303
In our previous study, we generated a strain of 19‐P (1030) in which artificial RNA interference (RNAi) was induced by transcribing a hairpin RNA of ~780‐bp stem. We utilized this RNAi‐induced strain to uncover RNAi‐related genes. Random insertional mutagenesis was performed to generate tag‐mutants that show a RNAi deficient phenotype. The 92‐12C is one such tag‐mutant, which bears a 14‐kb deletion in chromosome 1. Complementation of 92‐12C revealed that a protein gene, including a Cys‐Cys‐Cys‐His‐type zinc finger motif and an ankyrin repeat motif, is essential for effective RNAi in Chlamydomonas reinhardtii (Dangeard). BLAST analysis revealed that the zinc finger protein is homologous to an mRNA splicing‐related protein of other species. Therefore, one of the probable scenarios is that mRNA coding for RNAi‐related proteins cannot be properly spliced, which causes RNAi deficiency in the 92‐12C tag‐mutant. 相似文献