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971.
The amino acid sequence of the Tetrahymena calmodulin which specifically interacts with guanylate cyclase 总被引:13,自引:0,他引:13
M Yazawa K Yagi H Toda K Kondo K Narita R Yamazaki K Sobue S Kakiuchi S Nagao Y Nozawa 《Biochemical and biophysical research communications》1981,99(4):1051-1057
The amino acid sequence of the Tetrahymena calmodulin was determined. The protein is composed of 147 amino acids and the amino-terminal is acetylated. Compared to bovine brain calmodulin, there were eleven substitutions and one deletion of amino acid residues. The substitutions and deletion were concentrated in the carboxyl-terminal half of the molecule. Among the substitutions, those at positions 86 (Arg → Ile), 135 (Gln → His) and 143 (Gln → Arg) may introduce the functional difference. The deletion occurred near the carboxyl-terminal, this region being assumed to be exposed to the surface area (R.H. Kretsinger and C.D. Barry (1975)). The change in the sequence at this terminal region may be attributable to the specific activation of guanylate cyclase. 相似文献
972.
Addiction to psychostimulants elicits behavioral and biochemical changes that are assumed to be mediated by alterations of gene expression in the brain. The changes in gene expression after 3 weeks of withdrawal from chronic cocaine treatment were evaluated in the nucleus accumbens core and shell, dorsal prefrontal cortex and caudate using a complementary DNA (cDNA) array. The level of mRNA encoded by several genes was identified as being up- or down-regulated in repeated cocaine versus saline subjects. The results from the cDNA array were subsequently confirmed at the protein level with immunoblotting. Of particular interest, parallel up-regulation in protein and mRNA was found for the adenosine A1 receptor in the accumbens core, neuroglycan C in the accumbens shell, and the GluR5 glutamate receptor subtype in dorsal prefrontal cortex. However, there was an increase in TrkB protein in the nucleus accumbens core of cocaine-treated rats without a corresponding alteration in mRNA. These changes of gene expression in corticolimbic circuitry may contribute to the psychostimulant-induced behavioral changes associated with addiction. 相似文献
973.
Microfluidic PDMS (polydimethylsiloxane) bioreactor for large-scale culture of hepatocytes 总被引:5,自引:0,他引:5
Microfluidics could provide suitable environments for cell culture because of the larger surface-to-volume ratio and fluidic behavior similar to the environments in vivo. Such microfluidic environments are now used to investigate cell-to-cell interactions and behaviors in vitro, emulating situations observed in vivo, for example, microscale blood vessels modeled by microfluidic channels. These emulated situations cannot be realized by conventional technologies. In our previous works, microfluidic channels composed of two PDMS (poly(dimethylsiloxane)) layers were successfully used for Hep G2 cell culture. To achieve physiologically meaningful functions in vitro, a culture with a larger number of cells and higher density must be performed. This will require bioreactors with larger surface areas for cell attachment and sufficient amounts of oxygen and nutrition supply. For those purposes, we fabricated a bioreactor by stacking 10 PDMS layers together, i.e., four cell culture chambers, and a chamber dedicated to the oxygen supply inserted in the middle of the 10-stacked layers. The oxygen supply chamber is separated from the microfluidic channels for the culture medium perfusion by thin 300-microm PDMS walls. The high gas permeability of PDMS allows oxygen supply to the microfluidic channels through the thin walls. On the basis of the measurement of glucose consumption and albumin production, it is shown that cellular activity exhibits a gradual increase and saturation throughout the culture. We clearly observed that in the case of the microfluidic bioreactor for large-scale cultures, the oxygen chamber is indispensable to achieve longer and healthy cultures. In the present bioreactor, the cell density was found to be about 3-4 x 10(7) cells/cm(3), which is in the same order of magnitude as the conventional macroscale bioreactors. Consequently, by stacking single culture chambers and oxygen chambers in between, we could have a scalable method to realize the microfluidic bioreactor for large-scale cultures. 相似文献
974.
Toda M Kuo CH Borman SK Richardson RM Inoko A Inagaki M Collins A Schneider K Ono SJ 《The Journal of biological chemistry》2012,287(29):24516-24524
Accumulating evidence points to cross-talk between FcεRI and CC chemokine receptor (CCR)-mediated signaling pathways in mast cells. Here, we propose that vimentin, a protein comprising type III intermediate filament, participates in such cross-talk for CCL2/monocyte chemotactic protein 1 (MCP-1) production in mast cells, which is a mechanism for allergic inflammation. Co-stimulation via FcεRI, using IgE/antigen, and CCR1, using recombinant CCL3/macrophage inflammatory protein-1α (MIP-1α), increased expression of phosphorylated, disassembled, and soluble vimentin in rat basophilic leukemia (RBL)-2H3 cells expressing human CCR1 (RBL-CCR1 cells) and bone marrow-derived murine mast cells, both models of mucosal type mast cells. Furthermore, co-stimulation enhanced production of CCL2 as well as phosphorylation of MAPK. Treating the cells with p38 MAPK inhibitor SB203580, but not with MEK inhibitor PD98058, reduced CCL2 production, suggesting that p38 MAPK, but not ERK1/2, plays a critical role in the chemokine production. Immunoprecipitation analysis showed that vimentin interacts with phosphorylated ERK1/2 and p38 MAPKs in the co-simulated cells. Preventing disassembly of the vimentin by aggregating vimentin filaments using β,β'-iminodipropionitrile reduced the interaction of vimentin with phosphorylated MAPKs as well as CCL2 production in the cells. Taken together, disassembled vimentin interacting with phosphorylated p38 MAPK could mediate CCL2 production in mast cells upon FcεRI and CCR1 activation. 相似文献
975.
Interspecies Transmission of Feline Immunodeficiency Virus from the Domestic Cat to the Tsushima Cat (Felis bengalensis euptilura) in the Wild
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Yoshiaki Nishimura Yuko Goto Kumiko Yoneda Yasuyuki Endo Takuya Mizuno Masaharu Hamachi Hiroyuki Maruyama Hirotoshi Kinoshita Susumu Koga Mitsuru Komori Seigo Fushuku Kanji Ushinohama Masao Akuzawa Toshihiro Watari Atsuhiko Hasegawa Hajime Tsujimoto 《Journal of virology》1999,73(9):7916-7921
Feline immunodeficiency virus (FIV) was isolated from a wild-caught Tsushima cat (Felis bengalensis euptilura), an endangered Japanese nondomestic subspecies of leopard cat (F. bengalensis). Phylogenetic analysis of the env gene sequences indicated that the FIV from the Tsushima cat belonged to a cluster of subtype D FIVs from domestic cats. FIVs from both the Tsushima cat and the domestic cat showed similar levels of replication and cytopathicity in lymphoid cell lines derived from these two species. The results indicated the occurrence of interspecies transmission of FIV from the domestic cat to the Tsushima cat in the wild. 相似文献
976.
Glycoconjugate Journal - Glycosphingolipids (GSLs) are a specialized class of membrane lipids composed of a ceramide and a carbohydrate head group. GSLs are localized in cell membranes and were... 相似文献
977.
Hideki Maejima Ryo Nagashio Kengo Yanagita Yuko Hamada Yasuyuki Amoh Yuichi Sato Kensei Katsuoka 《PloS one》2014,9(7)
To identify diagnostic markers for psoriasis vulgaris and psoriatic arthritis, autoantibodies in sera from psoriasis vulgaris and psoriatic arthritis patients were screened by two-dimensional immunoblotting (2D-IB). Based on 2D-IB and MADLI TOF/TOF-MS analyses, eleven proteins each in psoriasis vulgaris and psoriatic arthritis were identified as autoantigens. Furthermore, serum levels of moesin, keratin 17 (K17), annexin A1 (ANXA1), and stress-induced phophoprotein-1 (STIP1), which were detected as autoantigens, were studied by dot blot analysis with psoriasis patients and healthy controls. The levels of moesin and STIP1 were significantly higher in sera from patients with psoriasis vulgaris than in the controls (moesin: P<0.05, STIP1: P<0.005). The area under the curve (AUC) for moesin and STIP1 between patients with psoraisis vulgaris and controls was 0.747 and 0.792, respectively. STIP1 and K17 levels were significantly higher in sera from patients with psoriatic arthritis than in those with psoriasis vulgaris (P<0.05 each). The AUC for STIP1 and K17 between patients with psoriatic arthritis and psoriasis vulgaris was 0.69 and 0.72, respectively. The STIP1 or moesin, CK17 serum level was not correlated with disease activity of psoriasis patients. These data suggest that STIP1 and moesin may be novel and differential sero-diagnostic markers for psoriasis vulgaris and psoriatic arthritis. 相似文献
978.
Morphological characters of adults and immature stages of Pyloetis mimosae (Stainton 1859) are redescribed mainly on the basis of material collected from seed pods of Leucaena leucocephala (Lem.) in the Ryukyus, Japan. Although the systematic position of this species in the family Tineidae has been problematic, we conclude that it should be placed in the subfamily Erechthiinae based on morphological characters. Pyloetis mimosae is newly recorded from Japan. 相似文献
979.
The TOG/XMAP215-related proteins play a role in microtubule dynamics at its plus end. Fission yeast Alp14, a newly identified TOG/XMAP215 family protein, is essential for proper chromosome segregation in concert with a second homologue Dis1. We show that the alp14 mutant fails to progress towards normal bipolar spindle formation. Intriguingly, Alp14 itself is a component of the Mad2-dependent spindle checkpoint cascade, as upon addition of microtubule-destabilizing drugs the alp14 mutant is incapable of maintaining high H1 kinase activity, which results in securin destruction and premature chromosome separation. Live imaging of Alp14-green fluorescent protein shows that during mitosis, Alp14 is associated with the peripheral region of the kinetochores as well as with the spindle poles. This is supported by ChIP (chromatin immunoprecipitation) and overlapping localization with the kinetochore marker Mis6. An intact spindle is required for Alp14 localization to the kinetochore periphery, but not to the poles. These results indicate that the TOG/XMAP215 family may play a central role as a bridge between the kinetochores and the plus end of pole to chromosome microtubules. 相似文献
980.
Abstract: We previously reported that growth-associated protein-43 (GAP-43) could be involved in the maintenance of elongated neurites and that a decline in protein kinase C activity may be involved in accumulation of GAP-43. In the present study, to clarify the functional significance of GAP-43 for neurite maintenance and acetylcholine (ACh) release, we prepared NG-G11 cells by transfection of GAP-43 cDNA into NG108-15 cells. NG-G11 cells expressed GAP-43 mRNA at levels approximately twice that in nontransfected or vector-transfected cells under control conditions and after treatment with dibutyryl cyclic AMP (diBu-cAMP) or 12-O-tetradecanoylphorbol 13-acetate (TPA) plus diBu-cAMP. Neurite outgrowth after addition of diBu-cAMP was greater in NG-G11 than in control cells. In NG-G11 cells, neurites elongated by treatment with diBu-cAMP for 72 h were maintained after removal of the drug. Treatment with TPA plus diBu-cAMP for 24 h induced neurite outgrowth in NG-G11 cells, although control cells required 72 h. Depolarization by 50 m M KCI induced ACh release in both NG-G11 and control cells treated with diBu-cAMP or TPA/diBu-cAMP. Although removal of the drugs following diBu-cAMP treatment reversed ACh release to nontreated levels in control cells, a high-K+ -induced level of ACh release remained in NG-G11 cells after removal of diBu-cAMP. ACh release induced by TPA plus diBu-cAMP for 24 h was further enhanced after removal of the drugs in NG-G11 cells, but it was not seen in control cells. These results suggest that levels of GAP-43 mRNA are correlated with neurite maintenance and the level of ACh release. Thus, GAP-43 may be involved in neuronal differentiation in NG108-15 cells. 相似文献