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131.
Shiho Ohnishi Mariko Murata Shinji Oikawa Yusuke Hiraku Shosuke Kawanishi 《Free radical research》2013,47(6):469-478
Hydrazobenzene is carcinogenic to rats and mice and azobenzene is carcinogenic to rats. Hydrazobenzene is a metabolic intermediate of azobenzene. To clarify the mechanism of carcinogenesis by azobenzene and hydrazobenzene, we investigated DNA damage induced by hydrazobenzene, using 32P-5′-end-labeled DNA fragments obtained from the c-Ha-ras-1 proto-oncogene and the p53 tumor suppressor gene. Hydrazobenzene caused DNA damage in the presence of Cu(II). Piperidine treatment enhanced the DNA damage greatly, suggesting that hydrazobenzene caused base modification and liberation. However, azobenzene did not cause DNA damage even in the presence of Cu(II). Hydrazobenzene plus Cu(II) caused DNA damage frequently at thymine residues. Catalase and a Cu(I)-specific chelator inhibited Cu(II)-mediated DNA damage by hydrazobenzene. Typical ·OH scavengers did not inhibit the DNA damage. The main active species is probably a metal oxygen complex, such as Cu(I)-OOH. Formation of 8-oxo-7, 8-dihydro-2′-deoxyguanosine was increased by hydrazobenzene in the presence of Cu(II). Oxygen consumption and UV-Visible spectroscopic measurements have shown that hydrazobenzene is autoxidized to azobenzene with H2O2 formation. It is considered that the metal-mediated DNA damage by hydrazobenzene through H2O2 generation may be relevant for the expression of carcinogenicity of azobenzene and hydrazobenzene. 相似文献
132.
The sixth International Symposium on Autophagy took place in October 2012 in Okinawa, Japan. It brought together scientists from all over the world to cultivate a better understanding of cutting‐edge autophagy research from molecular mechanisms to disease states. 相似文献
133.
Hideo Inoue Shiro Koizume Takahiro Yamauchi Kouichi Murata Eiko Ohtsuka 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1489-1490
Abstract Permanganate reaction of DNA oligomers containing an 8-oxoadenine or 5hydroxyuracil residue was studied, and the results were compared with those for an 8-oxoguanine-containing oligomers. We obtained similar results and found that the nucleotide residues neighboring the modified base were damaged and that the novel damage was induced by the oxidation of the modified base. 相似文献
134.
Akiko Kusunoki Akira Wada Naoko Kurosaki Tohru Kimura Kazuyuki Takai Naoki Yamamoto 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1705-1708
Abstract CXCR4 is both a chemokine receptor and an entry co-receptor for the T-cell line-adapted human immunodeficiency virus type 1 (HIV-1). To find a more efficacious therapeutic treatement of acquied immunodeficiency syndrome, we exmined the effects of antisense oligonucleotides on CXCR4 production. COS cells, stably expressing CXCR4 and CD4, were incubated with several kinds of oligonucleotides. Total human p24 antigen production was determined using an enzyme-linked immunosorbent assay system. An antisense phosphorothioate-modified oligonucleotide, complementary to the translation region of the CXCR4 mRNA, showed minimal inhibition of p24 antigen production at the high concentration of 2μM. On the other hand, the antisense phosphorothioate oligonucleotide, when used with transfection reagents, showed high efficiency at low concentrations, and confirmed the sequence-specific action. Interestingly, the oligonucleotide with the natual phosphodiester backbone, when used with the transfection reagents, also had high functional effects, comparable to the modified oligonucleotide. This defines the prerequisite criteria necessary for the design and the application of antisense oligonucleotides against HIV-1 in vivo. 相似文献
135.
Sachiko N. Isobe Hideki Hirakawa Shusei Sato Fumi Maeda Masami Ishikawa Toshiki Mori Yuko Yamamoto Kenta Shirasawa Mitsuhiro Kimura Masanobu Fukami Fujio Hashizume Tomoko Tsuji Shigemi Sasamoto Midori Kato Keiko Nanri Hisano Tsuruoka Chiharu Minami Chika Takahashi Tsuyuko Wada Akiko Ono Kumiko Kawashima Naomi Nakazaki Yoshie Kishida Mitsuyo Kohara Shinobu Nakayama Manabu Yamada Tsunakazu Fujishiro Akiko Watanabe Satoshi Tabata 《DNA research》2013,20(1):79-92
136.
Yusuke Shiromoto Satomi Kuramochi-Miyagawa Akito Daiba Shinichiro Chuma Ami Katanaya Akiko Katsumata Ken Nishimura Manami Ohtaka Mahito Nakanishi Toshinobu Nakamura Koichi Yoshinaga Noriko Asada Shota Nakamura Teruo Yasunaga Kanako Kojima-Kita Daisuke Itou Tohru Kimura Toru Nakano 《RNA (New York, N.Y.)》2013,19(6):803-810
piRNA (PIWI-interacting RNA) is a germ cell–specific small RNA in which biogenesis PIWI (P-element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi-like), one of the three mouse PIWI family members, is indispensable for piRNA production, DNA methylation of retrotransposons presumably through the piRNA, and spermatogenesis. The biogenesis of piRNA has been divided into primary and secondary processing pathways; in both of these MILI is involved in mice. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem (GS) cells, which are derived from testicular stem cells and possess a spermatogonial phenotype. We established MILI-null GS cell lines and their revertant, MILI-rescued GS cells, by introducing the Mili gene with Sendai virus vector. Comparison of wild-type, MILI-null, and MILI-rescued GS cells revealed that GS cells were quite useful for analyzing the molecular mechanisms of piRNA production, especially the primary processing pathway. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI using the cells and that gene knockdown of GPAT2 brought about impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for primary piRNA biogenesis. 相似文献
137.
The present study characterized the receptor‐dependent regulation of dendrite formation of noradrenaline (NA) and dopamine (DA) in cultured neurons obtained from embryonic day 16 rat cerebral cortex. Morphological diversity of cortical dendrites was analyzed on various features: dendrite initiation, dendrite outgrowth, and dendrite branching. Using a combination of immunocytochemical markers of dendrites and GABAergic neurons, we focused on the dendrite morphology of non‐GABAergic neurons. Our results showed that (1) NA inhibited the dendrite branching, (2) β adrenergic receptor (β‐AR) agonist inhibited the dendrite initiation, while promoted the dendrite outgrowth, (3) β1‐AR and β2‐AR were present in all the cultured neurons, and both agonists inhibited the dendrite initiation, while only β1‐AR agonist induced the dendrite branching; (4) DA inhibited the dendrite outgrowth, (5) D1 receptor agonist inhibited the dendrite initiation, while promoted the dendrite branching. In conclusion, this study compared the effects of NA, DA and their receptors and showed that NA and DA regulate different features on the dendrite formation of non‐GABAergic cortical neurons, depending on the receptors. © 2012 Wiley Periodicals, Inc. Develop Neurobiol 73: 370–383, 2013 相似文献
138.
Noboru Asada Yoshio Katayama Mari Sato Kentaro Minagawa Kanako Wakahashi Hiroki Kawano Yuko Kawano Akiko Sada Kyoji Ikeda Toshimitsu Matsui Mitsune Tanimoto 《Cell Stem Cell》2013,12(6):737-747
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139.
140.
Reyda Gonzalez-Nieves Akiko Iwahari DeSantis Mary L. Cutler 《Journal of cell communication and signaling》2013,7(4):279-293
Cell adhesion and migration are complex processes that require integrin activation, the formation and dissolution of focal adhesion (FAs), and linkage of actin cytoskeleton to the FAs. The IPP (ILK, PINCH, Parvin) complex regulates FA formation via binding of the adaptor protein ILK to β1 integrin, PINCH and parvin. The signaling protein Rsu1 is linked to the complex via binding PINCH1. The role of Rsu1 and PINCH1 in adhesion and migration was examined in non-transformed mammary epithelial cells. Confocal microscopy revealed that the depletion of either Rsu1 or PINCH1 by siRNA in MCF10A cells decreased the number of focal adhesions and altered the distribution and localization of β1 integrin, vinculin, talin and paxillin without affecting the levels of FA protein expression. This correlated with reduced adhesion, failure to spread or migrate in response to EGF and a loss of actin stress fibers and caveolae. In addition, constitutive phosphorylation of actin regulatory proteins occurred in the absence of PINCH1. The depletion of Rsu1 caused significant reduction in PINCH1 implying that Rsu1 may function by regulating levels of PINCH1. However, while both Rsu1- or PINCH1-depleted cells retained the ability to activate adhesion signaling in response to EGF stimulation, only Rsu1 was required for EGF-induced p38 Map Kinase phosphorylation and ATF2 activation, suggesting an Rsu1 function independent from the IPP complex. Reconstitution of Rsu1-depleted cells with an Rsu1 mutant that does not bind to PINCH1 failed to restore FAs or migration but did promote spreading and constitutive p38 activation. These data show that Rsu1-PINCH1 association with ILK and the IPP complex is required for regulation of adhesion and migration but that Rsu1 has a critical role in linking integrin-induced adhesion to activation of p38 Map kinase signaling and cell spreading. Moreover, it suggests that Rsu1 may regulate p38 signaling from the IPP complex affecting other functions including survival. 相似文献