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81.
Yeast mannan structure necessary for co-aggregation with Lactobacillus plantarum ML11-11 总被引:1,自引:0,他引:1
Hirayama S Furukawa S Ogihara H Morinaga Y 《Biochemical and biophysical research communications》2012,419(4):652-655
Lactic acid bacteria (LAB) Lactobacillus plantarum ML11-11, an isolate from Fukuyama pot vinegar, and yeast Saccharomyces cerevisiae form significant mixed-species biofilm with direct cell-cell contact. Co-aggregation of L. plantarum ML11-11 and S. cerevisiae cells, mediated by the interaction between surface protein(s) on L. plantarum ML11-11 cells and surface mannan of S. cerevisiae cells, contributes significantly to mixed-species biofilm formation. In this study, co-aggregation activities of yeast mutants that were deleted of genes related to mannan biosynthesis were investigated to clarify the mannan structures essential for interaction with L. plantarum ML11-11. Among the 12 deletion mutants which had various incomplete mannan structures, only the mnn2 mutant lost the co-aggregation activity. In the mnn2 mutant, the gene coding the activity of attaching first branching mannose residue to mannan main chain is deleted and therefore the mnn2 mutant has unbranched mannan. From this result, it is clarified that the specific structure, consisted of mannan main chain to which are attached side chains containing one or more mannose residues, is critical for co-aggregation with L. plantarum ML11-11. 相似文献
82.
Extensive and prolonged restoration of dystrophin expression with vivo-morpholino-mediated multiple exon skipping in dystrophic dogs 总被引:1,自引:0,他引:1
Yokota T Nakamura A Nagata T Saito T Kobayashi M Aoki Y Echigoya Y Partridge T Hoffman EP Takeda S 《Nucleic acid therapeutics》2012,22(5):306-315
Duchenne muscular dystrophy (DMD) is a severe and the most prevalent form of muscular dystrophy, characterized by rapid progression of muscle degeneration. Antisense-mediated exon skipping is currently one of the most promising therapeutic options for DMD. However, unmodified antisense oligos such as morpholinos require frequent (weekly or bi-weekly) injections. Recently, new generation morpholinos such as vivo-morpholinos are reported to lead to extensive and prolonged dystrophin expression in the dystrophic mdx mouse, an animal model of DMD. The vivo-morpholino contains a cell-penetrating moiety, octa-guanidine dendrimer. Here, we sought to test the efficacy of multiple exon skipping of exons 6-8 with vivo-morpholinos in the canine X-linked muscular dystrophy, which harbors a splice site mutation at the boundary of intron 6 and exon 7. We designed and optimized novel antisense cocktail sequences and combinations for exon 8 skipping and demonstrated effective exon skipping in dystrophic dogs in vivo. Intramuscular injections with newly designed cocktail oligos led to high levels of dystrophin expression, with some samples similar to wild-type levels. This is the first report of successful rescue of dystrophin expression with morpholino conjugates in dystrophic dogs. Our results show the potential of phosphorodiamidate morpholino oligomer conjugates as therapeutic agents for DMD. 相似文献
83.
Kensuke Kobayashi Minaho Uchiyama Hirobumi Takahashi Hiroshi Kawamoto Satoru Ito Takashi Yoshizumi Hiroshi Nakashima Tetsuya Kato Atsushi Shimizu Izumi Yamamoto Masanori Asai Hiroshi Miyazoe Akio Ohno Mioko Hirayama Satoshi Ozaki Takeshi Tani Yasuyuki Ishii Takeshi Tanaka Takanobu Mochidome Kiyoshi Tadano Osamu Okamoto 《Bioorganic & medicinal chemistry letters》2009,19(11):3096-3099
The synthesis and biological evaluation of new potent opioid receptor-like 1 (ORL1) antagonists are presented. Conversion of the thioether linkage of the prototype [It is reported prior to this communication as a consecutive series.: Kobayashi, K.; Kato, T.; Yamamoto, I.; Shimizu, A.; Mizutani, S.; Asai, M.; Kawamoto, H.; Ito, S.; Yoshizumi, T.; Hirayama, M.; Ozaki, S.; Ohta, H.; Okamoto, O. Bioorg. Med. Chem. Lett., in press] to the carbonyl linker effectively reduces susceptibility to P-glycoprotein (P-gp) efflux. This finding led to the identification of 2-cyclohexylcarbonylbenzimizole analogue 7c, which exhibited potent ORL1 activity, excellent selectivity over other receptors and ion channels, and poor susceptibility to P-gp. Compound 7c also showed satisfactory pharmacokinetic profiles and brain penetrability in laboratory animals. Furthermore, 7c showed good in vivo antagonism. Hence, 7c was selected as a clinical candidate for a brain-penetrable ORL1 antagonist. 相似文献
84.
Hiraoka K Yamamoto S Otsuru S Nakai S Tamai K Morishita R Ogihara T Kaneda Y 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(7):4297-4307
Immunization with dendritic cells (DCs) using various Ag-loading approaches has shown promising results in tumor-specific immunotherapy and immunoprevention. Fused cells (FCs) that are generated from DCs and tumor cells are one of effective cancer vaccines because both known and unknown tumor Ags are presented on the FCs and recognized by T cells. In this study, we attempted to augment antitumor immunity by the combination of DC-tumor FC vaccination with immunostimulatory oligodeoxynucleotides containing CpG motif (CpG ODN). Murine DCs were fused with syngeneic tumor cells ex vivo using inactivated hemagglutinating virus of Japan (Sendai virus). Mice were intradermally (i.d.) immunized with FCs and/or CpG ODN. Coadministration of CpG ODN enhanced the phenotypical maturation of FCs and unfused DCs, and the production of Th1 cytokines, such as IFN-gamma and IL-12, leading to the induction of tumor-specific CTLs without falling into T cell anergy. In addition, immunization with FCs + CpG ODN provided significant protection against lethal s.c. tumor challenge and spontaneous lung metastasis compared with that with either FCs or CpG ODN alone. Furthermore, among mice that rejected tumor challenge, the mice immunized with FCs + CpG ODN, but not the mice immunized with FCs or CpG ODN alone, completely rejected tumor rechallenge, indicating that CpG ODN provided long-term maintenance of tumor-specific immunity induced by FCs. Thus, the combination of DC-tumor FCs and CpG ODN is an effective and feasible cancer vaccine to prevent the generation and recurrence of cancers. 相似文献
85.
Enhancement of the endotoxin recognition pathway by ventilation with a large tidal volume in rabbits
Moriyama K Ishizaka A Nakamura M Kubo H Kotani T Yamamoto S Ogawa EN Kajikawa O Frevert CW Kotake Y Morisaki H Koh H Tasaka S Martin TR Takeda J 《American journal of physiology. Lung cellular and molecular physiology》2004,286(6):L1114-L1121
Ventilation with a small tidal volume (V(t)) is associated with better clinical outcomes than with a large V(t), particularly in critical settings, including acute lung injury. To determine whether V(t) influences the lipopolysaccaharide (LPS) recognition pathway, we studied CD14 expression in rabbit lungs and the release of TNF-alpha by cultured alveolar macrophages after 240 min of ventilation with a large (20 ml/kg) vs. a small (5 ml/kg) V(t). We also applied small or large V(t) to lungs instilled with 50 microg/kg of LPS. The alveolar macrophages collected after large V(t) ventilation revealed a 20-fold increase in LPS-induced TNF-alpha release compared with those collected after small V(t) ventilation, whereas TNF-alpha was undetectable without LPS stimulation. In animals ventilated with a large V(t), the expression of CD14 mRNA in whole lung homogenates and the expression of CD14 protein on alveolar macrophages, assessed by immunohistochemistry, were both significantly increased in the absence of LPS stimulation. A large V(t) applied to LPS-instilled lungs increased the pulmonary albumin permeability and TNF-alpha release into the plasma. These results suggest that mechanical stress caused by a large V(t) sensitizes the lungs to endotoxin, a phenomenon that may occur partially via the upregulation of CD14. 相似文献
86.
Satoru Kontani Eiichiro Nagata Tsuyoshi Uesugi Yusuke Moriya Natsuko Fujii Toshio Miyata Shunya Takizawa 《Neurochemical research》2013,38(12):2588-2594
Hypoxia-inducible factor 1 (HIF-1) is regulated by the oxygen-dependent hydroxylation of proline residues by prolyl hydroxylases (PHDs). We recently developed a novel PHD inhibitor, TM6008, that suppresses the activity of PHDs, inducing continuous HIF-1α activation. In this study, we investigated how TM6008 affects cell survival after hypoxic conditions capable of inducing HIF-1α expression and how TM6008 regulates PHDs and genes downstream of HIF-1α. After SHSY-5Y cells had been subjected to hypoxia, TM6008 was added to the cell culture medium under normoxic conditions. Apoptotic cell death was significantly augmented just after the hypoxic conditions, compared with cell death under normoxic conditions. Notably, when TM6008 was added to the media after the cells had been subjected to hypoxia, the expression level of HIF-1α increased and the number of cell deaths decreased, compared with the results for cells cultured in media without TM6008 after hypoxia, during the 7-day incubation period under normoxic conditions. Moreover, the protein expression levels of heme oxygenase 1, erythropoietin, and glucose transporter-3, which were genes downstream of HIF-1α, were elevated in media to which TM6008 had been added, compared with media without TM6008, during the 7-day incubation period under normoxic conditions. However, the protein expression levels of PHD2 and p53 which suppressed cell proliferation were suppressed in the media to which TM6008 had been added. Thus, TM6008, which suppresses the protein expressions of PHD2 and p53, might play an important role in cell survival after hypoxic conditions, with possible applications as a new compound for treatment after ischemic stroke. 相似文献
87.
Eguchi H Morii M Takahashi Y Sakai H Nakano M Ochiai H Shirahata A Hara Y Kawamura M Takeda K 《The Journal of membrane biology》2008,221(3):133-140
Leucines were mutated within the sequence L311ILGYTWLE319 of the extracellular loop flanking the third (M3) and fourth (M4) transmembrane segments (M3/M4 loop) of the Torpedo Na+,K+-ATPase α-subunit. Replacement of Leu311 with Glu resulted in a considerable loss of Na+,K+-ATPase activity. Replacement of Leu313 with Glu shifted the equilibrium of E1P and E2P toward E1P and reduced the rate of the E1P to E2P transition. The reduction of the transition rate and stronger inhibition of Na+,K+-ATPase activity by Na+ at higher concentrations together suggest that there is interference of Na+ release on the extracellular side in the Leu313 mutant. Thus, Leu313 could be in the pathway of Na+ exit. Replacement of Leu318 with Glu yielded an enzyme with significantly reduced apparent affinity for both vanadate and K+, with an equilibrium shifted toward E2P and no alteration in the transition rate. The reduced vanadate affinity is due to the lower rate of production of vanadate-reactive
[K+
2]E2 caused by inhibition of dephosphorylation through reduction of the K+ affinity of E2P. Thus, Leu318 may be a critical position in guiding external K+ to its binding site. 相似文献
88.
Maruyama S Miyajima N Bohgaki M Tsukiyama T Shigemura M Nonomura K Hatakeyama S 《Molecular and cellular biochemistry》2008,307(1-2):73-82
Ubiquitylation appears to be involved in the membrane trafficking system including endocytosis, exocytosis, and ER-to-Golgi
transport. We found that PIRH2, which was identified as an interacting protein for androgen receptor or p53, interacts with
and ubiquitylates the ε-subunit of coatmer complex, ε-COP. PIRH2 promotes the ubiquitylation of ε-COP in vitro and in vivo
and consequently promotes the degradation of ε-COP. The interaction between PIRH2 and ε-COP is affected by the presence of
androgen, and PIRH2 in the presence of androgen promotes ubiquitylation of ε-COP in vivo. Furthermore, overexpression of the
wild type of PIRH2 in prostate cancer cells causes downregulation of the secretion of prostate-specific antigen (PSA), a secretory
protein in prostate epithelial cells and one of diagnostic markers for prostate cancer. Our results indicate that PIRH2 functions
as a regulator for COP I complex. 相似文献
89.
Yoshimasa Takizawa Yong Qing Motoki Takaku Takako Ishida Yuichi Morozumi Takashi Tsujita Toshiaki Kogame Kouji Hirota Masayuki Takahashi Takehiko Shibata Hitoshi Kurumizaka Shunichi Takeda 《Nucleic acids research》2010,38(15):5059-5074
RAD51 is a key factor in homologous recombination (HR) and plays an essential role in cellular proliferation by repairing DNA damage during replication. The assembly of RAD51 at DNA damage is strictly controlled by RAD51 mediators, including BRCA1 and BRCA2. We found that human RAD51 directly binds GEMIN2/SIP1, a protein involved in spliceosome biogenesis. Biochemical analyses indicated that GEMIN2 enhances the RAD51–DNA complex formation by inhibiting RAD51 dissociation from DNA, and thereby stimulates RAD51-mediated homologous pairing. GEMIN2 also enhanced the RAD51-mediated strand exchange, when RPA was pre-bound to ssDNA before the addition of RAD51. To analyze the function of GEMIN2, we depleted GEMIN2 in the chicken DT40 line and in human cells. The loss of GEMIN2 reduced HR efficiency and resulted in a significant decrease in the number of RAD51 subnuclear foci, as observed in cells deficient in BRCA1 and BRCA2. These observations and our biochemical analyses reveal that GEMIN2 regulates HR as a novel RAD51 mediator. 相似文献
90.
Takaharu Yamamoto Junko Mochida Jun Kadota Miyoko Takeda Erfei Bi Kazuma Tanaka 《Molecular biology of the cell》2010,21(7):1237-1252
The assembly of filamentous actin is essential for polarized bud growth in budding yeast. Actin cables, which are assembled by the formins Bni1p and Bnr1p, are thought to be the only actin structures that are essential for budding. However, we found that formin or tropomyosin mutants, which lack actin cables, are still able to form a small bud. Additional mutations in components for cortical actin patches, which are assembled by the Arp2/3 complex to play a pivotal role in endocytic vesicle formation, inhibited this budding. Genes involved in endocytic recycling were also required for small-bud formation in actin cable-less mutants. These results suggest that budding yeast possesses a mechanism that promotes polarized growth by local recycling of endocytic vesicles. Interestingly, the type V myosin Myo2p, which was thought to use only actin cables to track, also contributed to budding in the absence of actin cables. These results suggest that some actin network may serve as the track for Myo2p-driven vesicle transport in the absence of actin cables or that Myo2p can function independent of actin filaments. Our results also show that polarity regulators including Cdc42p were still polarized in mutants defective in both actin cables and cortical actin patches, suggesting that the actin cytoskeleton does not play a major role in cortical assembly of polarity regulators in budding yeast. 相似文献