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排序方式: 共有2455条查询结果,搜索用时 15 毫秒
901.
Yusuke Nakatsu Yasuka Matsunaga Takeshi Yamamotoya Koji Ueda Masa-ki Inoue Yu Mizuno Mikako Nakanishi Tomomi Sano Yosuke Yamawaki Akifumi Kushiyama Hideyuki Sakoda Midori Fujishiro Akihide Ryo Hiraku Ono Tohru Minamino Shin-Ichiro Takahashi Haruya Ohno Masayasu Yoneda Tomoichiro Asano 《Cell reports》2019,26(12):3221-3230.e3
902.
Akira Asanome Jun-ichi Kawabe Motoki Matsuki Maki Kabara Yoshiki Hira Hiroki Bochimoto Atsushi Yamauchi Tatsuya Aonuma Naofumi Takehara Tsuyoshi Watanabe Naoyuki Hasebe 《Biochemical and biophysical research communications》2014
An immature vasa vasorum in the adventitia of arteries has been implicated in induction of the formation of unstable atherosclerotic plaques. Normalization/maturation of the vasa vasorum may be an attractive therapeutic approach for arteriosclerotic diseases. Nerve growth factor (NGF) is a pleotropic molecule with angiogenic activity in addition to neural growth effects. However, whether NGF affects the formation of microvessels in addition to innervation during pathological angiogenesis is unclear. In the present study, we show a new role for NGF in neovessels around injured arterial walls using a novel in vivo angiogenesis assay. 相似文献
903.
Keisuke Okada Hideaki Miyake Kohei Yamaguchi Koji Chiba Kazuhiro Maeta Shymaa E. Bilasy Hironori Edamatsu Tohru Kataoka Masato Fujisawa 《Biochemical and biophysical research communications》2014
Small GTPase Rap1 has been implicated in the proper differentiation of testicular germ cells. In the present study, we investigated the functional significance of RA-GEF-2/Rapgef6, a guanine nucleotide exchange factor for Rap1, in testicular differentiation using mice lacking RA-GEF-2. RA-GEF-2 was expressed predominantly on the luminal side of the seminiferous tubules in wild-type mice. No significant differences were observed in the body weights or hormonal parameters of RA-GEF-2−/− and wild-type mice. However, the testes of RA-GEF-2−/− male mice were significantly smaller than those of wild-type mice and were markedly atrophied as well as hypospermatogenic. The concentration and motility of epididymal sperm were also markedly reduced and frequently had an abnormal shape. The pregnancy rate and number of fetuses were markedly lower in wild-type females after they mated with RA-GEF-2−/− males than with wild-type males, which demonstrated the male infertility phenotype of RA-GEF-2−/− mice. Furthermore, a significant reduction and alteration were observed in the expression level and cell junctional localization of N-cadherin, respectively, in RA-GEF-2−/− testes, which may, at least in part, account for the defects in testicular differentiation and spermatogenesis in these mice. 相似文献
904.
Takao Fuchigami Toshiro Kibe Hirofumi Koyama Shosei Kishida Mikio Iijima Yoshiaki Nishizawa Hiroshi Hijioka Tomomi Fujii Masahiro Ueda Norifumi Nakamura Tohru Kiyono Michiko Kishida 《Biochemical and biophysical research communications》2014
Ameloblastoma is an odontogenic benign tumor that occurs in the jawbone, which invades bone and reoccurs locally. This tumor is treated by wide surgical excision and causes various problems, including changes in facial countenance and mastication disorders. Ameloblastomas have abundant tumor stroma, including fibroblasts and immune cells. Although cell-to-cell interactions are considered to be involved in the pathogenesis of many diseases, intercellular communications in ameloblastoma have not been fully investigated. In this study, we examined interactions between tumor cells and stromal fibroblasts via soluble factors in ameloblastoma. 相似文献
905.
Mitsuo Nunome Gohta Kinoshita Morihiko Tomozawa Harumi Torii Rikyu Matsuki Fumio Yamada Yoichi Matsuda Hitoshi Suzuki 《Biological journal of the Linnean Society. Linnean Society of London》2014,111(4):761-776
Seasonal changes in fur colour in some mammalian species have long attracted the attention of biologists, especially in species showing population variation in these seasonal changes. Genetic differences among populations that show differences in seasonal changes in coat colour have been poorly studied. Because the Japanese hare (Lepus brachyurus) has two allopatric morphotypes that show remarkably different coat colours in winter, we examined the population genetic structure of the species using partial sequences of the SRY gene and six autosomal genes: three coat colour‐related genes (ASIP, TYR, and MC1R) and three putatively neutral genes (TSHB, APOB, and SPTBN1). The phylogenetic tree of SRY sequences exhibited two distinct lineages that diverged approsimately 1 Mya. Although the two lineages exhibited a clear allopatric distribution, it was not consistent with the distribution of morphotypes. In addition, six nuclear gene sequences failed to reveal genetic differences between morphotypes. Population network trees for 11 expedient populations divided the populations into four groups. Genetic structure analysis revealed an admixture of four genetic clusters in L. brachyurus, two of which showed large genetic differences. Our results suggest ancient vicariance in L. brachyurus, and we detected no genetic differences between the two morphotypes. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 761–776. 相似文献
906.
For construction of the bacterial flagellum, which is responsible for bacterial motility, the flagellar type III export apparatus utilizes both ATP and proton motive force across the cytoplasmic membrane and exports flagellar proteins from the cytoplasm to the distal end of the nascent structure. The export apparatus consists of a membrane-embedded export gate made of FlhA, FlhB, FliO, FliP, FliQ, and FliR and a water-soluble ATPase ring complex consisting of FliH, FliI, and FliJ. FlgN, FliS, and FliT act as substrate-specific chaperones that do not only protect their cognate substrates from degradation and aggregation in the cytoplasm but also efficiently transfer the substrates to the export apparatus. The ATPase ring complex facilitates the initial entry of the substrates into the narrow pore of the export gate. The export gate by itself is a proton-protein antiporter that uses the two components of proton motive force, the electric potential difference and the proton concentration difference, for different steps of the export process. A specific interaction of FlhA with FliJ located in the center of the ATPase ring complex allows the export gate to efficiently use proton motive force to drive protein export. The ATPase ring complex couples ATP binding and hydrolysis to its assembly–disassembly cycle for rapid and efficient protein export cycle. This article is part of a Special Issue entitled: Protein trafficking and secretion in bacteria. Guest Editors: Anastassios Economou and Ross Dalbey. 相似文献
907.
Chengwei Liu Motoyoshi Noike Atsushi Minami Hideaki Oikawa Tohru Dairi 《Applied microbiology and biotechnology》2014,98(1):199-206
Paxilline is an indole-diterpene produced by Penicillium paxilli. Six genes (paxB, C, G, M, P, and Q) in paxilline biosynthetic gene cluster were previously shown to be responsible for paxilline biosynthesis. In this study, we have characterized paxD, which is located next to paxQ and has weak similarities to fungal dimethylallyl tryptophan synthase genes. PaxD was overexpressed in Escherichia coli and the purified enzyme was used for in vitro analysis. When paxilline and dimethylallyl diphosphate were used as substrates, one major and one minor product, which were identified as di-prenyl paxilline and mono-prenyl paxilline by liquid chromatography–mass spectrometry analysis, were formed. The structure of the major product was determined to be 21,22-diprenylated paxilline, showing that PaxD catalyzed the successive di-prenylation. Traces of both products were detected in culture broth of P. paxilli by liquid chromatography–mass spectrometry analysis. The enzyme is likely to be a dimer and required no divalent cations. The optimum pH and temperature were 8.0 and 37 °C, respectively. The Km values were calculated as 106.4?±?5.4 μM for paxilline and 0.57?±?0.02 μM for DMAPP with a kcat of 0.97?±?0.01/s. 相似文献
908.
909.
Keiko Taguchi Ikuo Hirano Tohru Itoh Minoru Tanaka Atsushi Miyajima Akira Suzuki Hozumi Motohashi Masayuki Yamamoto 《Molecular and cellular biology》2014,34(5):900-913
Keap1-Nrf2 system plays a central role in the stress response. While Keap1 ubiquitinates Nrf2 for degradation under unstressed conditions, this Keap1 activity is abrogated in response to oxidative or electrophilic stresses, leading to Nrf2 stabilization and coordinated activation of cytoprotective genes. We recently found that nuclear accumulation of Nrf2 is significantly increased by simultaneous deletion of Pten and Keap1, resulting in the stronger activation of Nrf2 target genes. To clarify the impact of the cross talk between the Keap1-Nrf2 and Pten–phosphatidylinositide 3-kinase–Akt pathways on the liver pathophysiology, in this study we have conducted closer analysis of liver-specific Pten::Keap1 double-mutant mice (Pten::Keap1-Alb mice). The Pten::Keap1-Alb mice were lethal by 1 month after birth and displayed severe hepatomegaly with abnormal expansion of ductal structures comprising cholangiocytes in a Nrf2-dependent manner. Long-term observation of Pten::Keap1-Alb::Nrf2+/− mice revealed that the Nrf2-heterozygous mice survived beyond 1 month but developed polycystic liver fibrosis by 6 months. Gsk3 directing the Keap1-independent degradation of Nrf2 was heavily phosphorylated and consequently inactivated by the double deletion of Pten and Keap1 genes. Thus, liver-specific disruption of Keap1 and Pten augments Nrf2 activity through inactivation of Keap1-dependent and -independent degradation of Nrf2 and establishes the Nrf2-dependent molecular network promoting the hepatomegaly and cholangiocyte expansion. 相似文献
910.
Ken-ichi Nakashima Tohru Murakami Hiroki Tanabe Makoto Inoue 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014