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111.
Hisashi Koike Zen Kouchi Tadatoshi Kinouchi Tatsuya Maeda Hiroyuki Sorimachi Takaomi C. Saido Kei Maruyama Akira Okuyama Koichi Suzuki Shoichi Ishiura 《Cytotechnology》2000,33(1-3):213-219
Thimet oligopeptidase (TOP) is a thiol- andmetallo-dependent peptidase and has been shown to beone of the -secretase candidates. TOPexpressed in COS cells cleaved amyloid precursorprotein (APP) at the -secretase site, and wefound a proteolytic product of APP called secretedform of APP by -secretase (sAPP) in theconditioned media. Here we demonstrate thatsAPP was increased in conditioned media whenTOP was coexpressed in COS cells with APP and treatedwith an ADAM inhibitor SI-27. In addition, althoughTOP expressed in COS cell was localized at nuclei orGolgi apparatus, it exclusively colocalized at Golgiapparatus when APP was coexpressed with TOP. 相似文献
112.
Ui M Mizutani T Takada M Arai T Ito T Murakami M Koike C Watanabe T Yoshimatsu K Iba H 《Biochemical and biophysical research communications》2000,278(1):97-105
We investigated the role of endogenous AP-1 in human tumor cell lines by introducing SupJunD-1, a dominant-negative mutant of AP-1, using vesicular stomatitis virus G protein (VSV-G)-pseudotyped retrovirus vectors. Single inoculation of six human tumor cell lines, originating from osteosarcomas, non-small cell lung carcinomas or cervical carcinomas, with recombinant SupJunD-1 virus at a high multiplicity of infection readily inhibited colony formation in soft agar. We detected no significant changes in expression levels of AP-1 components c-Jun or Fra-1, adhesion molecules CD44 or E-cadherin, or cell cycle regulator p53, which are encoded by genes previously reported to be under the control of AP-1 in some mouse or human cell lines. By varying the dosage of VSV-G-pseudotyped retrovirus, we were able to change the proviral copy number of supjunD-1 from 1 to approximately 10 and monitor suppression of endogenous AP-1 function as assessed by growth characteristics of the tumor cell lines, we found a SupJunD-1 dosage which significantly suppressed anchorage-independent growth without affecting the cellular growth in monolayer cultures at all. We conclude that endogenous AP-1 levels necessary for oncogenic activity are much higher than those sufficient to support normal growth. 相似文献
113.
Rzhetsky A Koike T Kalachikov S Gomez SM Krauthammer M Kaplan SH Kra P Russo JJ Friedman C 《Bioinformatics (Oxford, England)》2000,16(12):1120-1128
MOTIVATION: In order to aid in hypothesis-driven experimental gene discovery, we are designing a computer application for the automatic retrieval of signal transduction data from electronic versions of scientific publications using natural language processing (NLP) techniques, as well as for visualizing and editing representations of regulatory systems. These systems describe both signal transduction and biochemical pathways within complex multicellular organisms, yeast, and bacteria. This computer application in turn requires the development of a domain-specific ontology, or knowledge model. RESULTS: We introduce an ontological model for the representation of biological knowledge related to regulatory networks in vertebrates. We outline a taxonomy of the concepts, define their 'whole-to-part' relationships, describe the properties of major concepts, and outline a set of the most important axioms. The ontology is partially realized in a computer system designed to aid researchers in biology and medicine in visualizing and editing a representation of a signal transduction system. 相似文献
114.
Enhancement of oxidised low-density lipoprotein uptake by macrophages in response to macrophage migration inhibitory factor 总被引:3,自引:0,他引:3
We examined the expression of macrophage migration inhibitory factor (MIF) mRNA in murine macrophage cell line (RAW 264.7 cells) in response to oxidized low-density lipoprotein (oxLDL), and investigated the influence of MIF on the uptake and degradation of oxLDL by RAW 264.7 cells. MIF mRNA expression was markedly upregulated in the presence of oxLDL. Consistent with this, the MIF level of the culture medium was increased by stimulation with oxLDL in dose- and time-dependent manners. Next, we added recombinant rat MIF to the culture medium and examined its effects on the uptake of(125)I-labelled oxLDL. Pretreatment with MIF enhanced both the uptake and degradation of(125)I-oxLDL. Taken together, these results suggest that MIF released from macrophages in response to oxLDL stimulates oxLDL uptake and degradation in an autocrine and paracrine fashion, which potentially results in atherosclerosis. 相似文献
115.
Hasegawa Y Hakusui S Hirayama M Ieda T Koike Y Matsuoka Y Takahashi A 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2000,7(2):P159-P160
Neurogenic orthostatic hypotension (OH) often causes troublesome symptoms such as dizziness, syncope and falling, interfering active daily life or various therapies in rehabilitation. Nonpharmacologic measures for treating patients with OH include wearing elastic leotard, head-up tilting at night, etc. Elastic garment or antigravity suits is certainly effective, but it may be uncomfortable and not practical. Although elastic bandage (EB) bound on the lower limbs has been thought to be useful, there is few clinical report about its beneficial evidence. We investigated short-term clinical effects of commercially available EB on OH, and estimated the mechanism of its effectiveness by measuring some blood pressure-related humoral variables in neurodegenerative patients with OH. 相似文献
116.
117.
Thylakoid membranes and Photosystem I (PS I) complexes were isolated from a glaucocystophyte, Cyanophora paradoxa, which is thought to have the most primitive ‘plastids’, and the proteins related to PS I were examined. The intrinsic light-harvesting
chlorophyll protein complexes of PS I (LHC I) were not detected by an immunological method. The PS I complexes consisted of
at least eight low-molecular-mass proteins in addition to PS I reaction center proteins. The N-terminal sequence of the PsaD
protein has higher homology to that of Chlamydomonas reinhardtii and land plants, than to that of other algae or cyanobacteria. On the other hand, the PsaL sequence has the highest homology
to those of cyanobacteria. Taking into account the other sequences of PS I components whose genes are encoded in the cyanelle
genome, and the fact that LHC I is not detected, it is concluded that PS I of C. paradoxa has chimeric characteristics of both ‘green’ lineages and cyanobacteria.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
118.
The plasmid pCI6, carrying the attP site of the temperate phage phiU, integrates into the attB site on the chromosome of Rhizobium leguminosarum biovar trifolii strain 4S. The 4 kb EcoRI-HindIII region of pCI6 involved in site-specific integration was subcloned as the attP fragment of phage phiU and sequenced. The attL fragment, one of the new DNA junctions generated from the insertion of pCI6 into the chromosome of the host Rhizobium, was used as a hybridization probe for isolation of the attB fragment of strain 4S. The nucleotide sequence of the 2 kb PstI fragment of strain 4S, which hybridized with the attL fragment, was decided and compared with that of the attP fragment. A 53 bp common sequence was expected to be the core sequence of site-specific integration between phage phiU and strain 4S. One of the ORFs on the attP fragment, which was located adjacent to the core sequence, had structural homology to the integrase family. However, the attB fragment showed high homology with the tRNA genes of Agrobacterium tumefaciens and E. coli. A 47 bp sequence of the 53 bp core sequence overlapped with this tRNA-like sequence. This indicates that the target site of phage phiU integration is the putative tRNA gene on the chromosome of the Rhizobium host. 相似文献
119.
Y Kawasaki J Koike K Ijiri M Yamashita K Sugiura K Kobayashi K Seki Y Ishikawa H Mizutani J Poynter T MacCallum G Anderson 《Biological Sciences in Space》1998,12(4):373-376
Distribution of microorganisms and cellular structure of an Autonomous Biological Systems (ABS) were studied with a special attention to the effect of space environments. Viable cell densities measured by the direct fluorescence microscopic method were in the order of 10(5) cells/ml for fractions 1 (upper suspension) and 2 (lower suspension), and 10(6) cells/ml for fraction 3 (sediments). These values were 10 to 100 times larger than the values obtained by the classical colony forming unit method. No difference between flight and ground samples was observed in the vertical distribution of viable microorganisms when fractionation and analysis were carried out after recovery. Intracellular distribution of chloroplasts in higher green plants, Ceratophyllum demersum, of flight samples was disturbed after 10 days of flight (24hrs/day light on). After 4 months of flight (Mir/STS-79/81) with 24 hrs light on, Ceratophyllum demersum was completely disintegrated. On the other hand, in the second 4-months-flight experiment with 16 hrs/day light on, Ceratophyllum demersum was only slightly deteriorated. 相似文献
120.
Hideyuki Nagao Hiroaki Arai Satoko Oshima Masanori Koike Tsutomu Iijima 《Mycoscience》1998,39(1):37-42
An isolate ofVerticillum dahliae Vdp-4, pathogenic to both tomato and pepper (tomato-pepper pathotype), was examined for its vegetative compatibility with
testers of the Japanese vegetative compatibility group (subgroups J1, J2, and J3). Seven isolates ofV. dahliae from the same field as Vdp-4 in Misato, Nagano Pref. and two isolates from Hokkaido were separately determined as either
tomato pathotype (B) or pepper pathotype (C). Isolate 5922 previously reported as tomato-pepper pathotype was also examined.
Compatiblenit1 and NitM mutants were obtained from all isolates except for isolates Vdp-3 and Vdt-10. The isolate of tomato-pepper pathotype
Vdp-4 showed a strong reaction with VCGJ1 and J3 and was thus assigned to J3. Seven of these isolates showed compatibility
and were assigned into three provisional subgroups. The isolate 5922 was self-incompatible. 相似文献