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861.
We identified and characterized a gene encoding a protein that was 92% identical to human ribosomal protein L39. This gene was located on the long arm of chromosome 3, and was composed of three exons and two long introns. Analysis of mRNA expression in 16 types of normal human tissues showed that this gene was expressed specifically in the testis, in sharp contrast to the ubiquitous expression of the ribosomal protein L39 gene. Surprisingly, the new gene was expressed in 19 out of 24 human cancer samples of various tissue origins. When the new gene was expressed in the cell, a translated product was observed by immunofluorescence microscopy in the nucleus, especially strongly in the nucleolus, and in the cytoplasm. Association of this protein with the large subunit of cytoplasmic ribosomes was detected by polyacrylamide-agarose composite gel electrophoresis followed by immunodetection. These immunochemical data suggest a relationship between the new gene and the ribosome.  相似文献   
862.
TAK1 mitogen-activated protein kinase kinase kinase (MAP3K) is activated by its specific activator, TAK1-binding protein 1 (TAB1). A constitutively active TAK1 mutant has not yet been generated due to the indispensable requirement of TAB1 for TAK1 kinase activity. In this study, we generated a novel constitutively active TAK1 by fusing its kinase domain to the minimal TAK1-activation domain of TAB1. Co-immunoprecipitation assay demonstrated that these domains interacted intra-molecularly. The TAK1-TAB1 fusion protein showed a significant MAP3K activity in vitro and activated c-Jun N-terminal kinase/p38 MAPKs and IkappaB kinase in vivo, which was followed by increased production of interleukin-6. These results indicate that the fusion protein is useful for characterizing the physiological roles of the TAK1-TAB1 complex.  相似文献   
863.
Regional gene therapy, which involves the delivery of growth factors to a specific anatomic site, has the potential to enhance bone formation in clinical application. Helper-dependent adenoviral vectors, which have deleted all of the viral coding regions, have been shown to be safe and highly efficient with long-lasting transgene expression. In this study, we constructed a helper-dependent adenoviral vector producing bone morphogenetic protein-2 (AdHDBMP-2). The AdHDBMP-2 increased the alkaline phosphatase activity of W-20-17 cells in vitro. In addition, when AdHDBMP-2 infected rat bone marrow cells were implanted into the hindlimbs of SCID mice, orthotopic bone formation was shown at 2 weeks. To our knowledge, this is the first study to demonstrate bone formation with the helper-dependent adenoviral vector with the BMP-2 expression cassette. This type of gene therapy vector could prove to be highly useful for bone augmentation in patients with bone loss associated with trauma, revision total joint arthroplasty, or cancer.  相似文献   
864.
865.
A powdery mildew fungus on leaves of Dalbergia cultrata var. cultrata (Fabaceae) collected at the Queen Sirikit Botanical Garden in northern Thailand is proven to be a new species of the genus Brasiliomyces and is described as B. chiangmaiensis sp. nov. with light and SEM micrographs. Differences in known Brasiliomyces species are discussed, and a key to species of this genus is provided.  相似文献   
866.
Exobasidium symploci-japonicae var. carpogenum, causing Exobasidium fruit deformation on Symplocos lucida collected in Fukuoka Prefecture, Japan, is newly described based on morphological observations of hymenial structure and mode of basidiospore germination. This new variety differs morphologically from the type variety, particularly in the septal number of basidiospores and in the shapes and sizes of conidia formed on the medium. Colonies of this new variety are also distinguishable from those of the type variety by yeast-like growth, morphology, and color of colonies.Contribution no.178, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   
867.
Response to predators may not be identical between different prey species with different life histories and body sizes, particularly when the threat of predation is not great. To clarify this hypothesis, we introduced two prey species (10 Japanese dace, Tribolodon hakonensis, and 10 pale chub, Zacco platypus) into each experimental pond (in total, 8 ponds×4 trials) in which benthic algae had been allowed to grow. The presence or absence of Far Eastern catfish, Silurus asotus, and a refuge for prey fish was used to produce four treatments. The presence of catfish and/or a refuge did not affect either the feeding behavior or growth rate of Japanese dace. In contrast, when catfish were present and no refuge was available, the incidence of bottom feeding for pale chub greatly decreased. Pale chub growth rate was low when catfish were present and a refuge was available, indicating that pale chub spent more of their time in the refuge and lost opportunities of acquiring food. Japanese dace can reach a threshold size at which the prey are safe from predation, but pale chub cannot, and this may explain the differences in response to predators of the two species.  相似文献   
868.
MOTIVATION: Readthrough is an unusual process in which a stop codon is misread or skipped. Recently it has been shown that some translation is regulated by the readthrough reactions although the complete mechanism is not clear. Therefore, the discovery of 'readthrough genes' is important for further investigation of their cellular roles, which may provide additional insights into the mechanism of translational regulation. RESULTS: We constructed a system that lists candidates of readthrough genes based on the existence of a 'protein motif' at the 3' untranslated region (UTR). Using this system, we extracted 85 candidates from 4082 nucleic acid sequences of Drosophila melanogaster in GenBank database. The sequences of these candidates had a slightly more stable secondary structure and different base preferences compared to the non-candidates. As these features are known to have an effect on readthrough events, we would like to suggest that these candidates contain actual readthrough genes. AVAILABILITY: Source code of the system is available upon request.  相似文献   
869.
The under-ice behavior of two free-ranging female Weddell seals (Leptonychotes weddellii) was studied using geomagnetic, acceleration and velocity sensors at Big Razorback Island in McMurdo Sound, Antarctica. The seals' body angle and posture were calculated from the acceleration data and the heading from the geomagnetic intensity data. Together with swim speed, the seals' three-dimensional underwater dive path, heading and even posture were reconstructed for each dive. Each instrument was deployed for 2 days, during which time these females made multiple, deep (₞ m) dives, with average maximum depths of 236ᆯ m (n=4) and 244끁 m (n=40). Each seal appeared to choose a particular heading on which to descend. These headings were significantly different between seals and bouts (Watson's U2 test, P<0.05). These new instruments and methodologies are shown to provide valuable information on the fine-scale and complex movements of diving animals.  相似文献   
870.
Entrainment of the circadian rhythm has 2 aspects, period and phase adjustments, which are established simultaneously in most nonhuman circadian systems. The human circadian system is unique in its functional structure in which 2 different subsystems are involved; one is the circadian pacemaker analogous to that located in the suprachiasmatic nucleus, and the other is the oscillatory system of unknown nature that drives the rest-activity cycle. The human circadian system shows the endogenous period very close to 24 h under entrainment and less sensitive to photic stimuli than under free running, which may explain stable entrainment in the real word where natural sun lights are unpredictable in terms of the intensity and time of appearance. On the other hand, nonphotic entrainment seems to play a significant role in phase adjustment of the human circadian system. Nonphotic zeitgebers initially directed to the rest-activity cycle may affect the circadian pacemaker through feedback and/or associated LD cycles.  相似文献   
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