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51.
Simon D X Chuong Robert T Mullen Douglas G Muench 《The Journal of biological chemistry》2002,277(4):2419-2429
The control of subcellular mRNA localization and translation is often mediated by protein factors that are directly or indirectly associated with the cytoskeleton. We report the identification and characterization of a rice seed protein that possesses both RNA and microtubule binding activities. In vitro UV cross-linking assays indicated that this protein binds to all mRNA sequences tested, although there was evidence for preferential binding to RNAs that contained A-C nucleotide sequence motifs. The protein was purified to homogeneity using a two-step procedure, and amino acid sequencing identified it as the multifunctional protein (MFP), a peroxisomal enzyme known to possess a number of activities involved in the beta-oxidation of fatty acids. The recombinant version of this rice MFP binds to RNA in UV cross-linking and gel mobility shift experiments, co-sediments specifically with microtubules, and possesses at least two enzymatic activities involved in peroxisomal fatty acid beta-oxidation. Taken together these data suggest that MFP has an important role in mRNA physiology in the cytoplasm, perhaps in regulating the localization or translation of mRNAs through an interaction with microtubules, in addition to its peroxisomal function. 相似文献
52.
Hiroyuki Kozu Isao Kobayashi Mitsutoshi Nakajima Kunihiko Uemura Seigo Sato Sosaku Ichikawa 《Food biophysics》2010,5(4):330-336
This paper uses computational fluid dynamics to simulate and analyze intragastric fluid motions induced by human peristalsis.
We created a two-dimensional computational domain of the distal stomach where peristalsis occurs. The motion of the gastric
walls induced by an antral contraction wave (ACW) on the wall of the computational domain was well simulated using a function
defined in this study. Retropulsive flow caused by ACW was observed near the occluded region, reaching its highest velocity
of approximately 12 mm/s in the narrowest region. The viscosity of the model gastric contents applied in this study hardly
affected the highest velocity, but greatly affected the velocity profile in the computational domain. The shear rate due to
gastric fluid motion was calculated using the numerical output data. The shear rate reached relatively high values of approximately
20 s−1 in the most occluded region. The shear rate profile was almost independent of the fluid viscosity. We also simulated mass
transfer of a gastric digestive enzyme (pepsin) in model gastric content when peristalsis occurs on the gastric walls. The
visualized simulation results suggest that gastric peristalsis is capable of efficiently mixing pepsin secreted from the gastric
walls with an intragastric fluid. 相似文献
53.
Patrizia Vaccino Heinz-Albert Becker Andrea Brandolini Francesco Salamini Benjamin Kilian 《Molecular genetics and genomics : MGG》2009,281(3):289-300
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure
to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat,
where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes
is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented
by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes
of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful
sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid
wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
54.
Background
Radial chromosome positioning in interphase nuclei is nonrandom and can alter according to developmental, differentiation, proliferation, or disease status. However, it is not yet clear when and how chromosome repositioning is elicited. 相似文献55.
Robert C. Tait Byron E. Froman Debbie L. Laudencia-Chingcuanco Leslie D. Gottlieb 《Plant molecular biology》1988,11(4):381-388
Nuclear genes that appear to encode both cytosolic and plastid isozymes of phosphoglucose isomerase (PGI), an essential glycolytic enzyme, have been isolated from three diploid species of the annual wild flower genus Clarkia (Onagraceae). The genes do not contain introns and are expressed to varying degrees in Escherichia coli when cloned in either Charon 35 phage or pUC plasmid vectors. The PGI proteins synthesized in E. coli form dimers, are catalytically active, and their electrophoretic mobilities are similar to those of appropriate Clarkia PGIs. The nucleotide sequence of a gene encoding a plastid isozyme of C. unguiculata is described. 相似文献
56.
Background
In heterogeneous environments, sex-biased dispersal could lead to environmental adaptive parental effects, with offspring selected to perform in the same way as the parent dispersing least, because this parent is more likely to be locally adapted. We investigate this hypothesis by simulating varying levels of sex-biased dispersal in a patchy environment. The relative advantage of a strategy involving pure maternal (or paternal) inheritance is then compared with a strategy involving classical biparental inheritance in plants and in animals. 相似文献57.
Robert Layton 《The journal of the Royal Anthropological Institute》2003,9(3):447-464
In his book, Art and agency , Alfred Gell presents a theory of art based neither on aesthetics nor on visual communication. Art is defined by the distinctive function it performs in advancing social relationships through 'the abduction of agency'. Art objects are indexes of the artist's or model's agency. This article examines Gell's use of agency, particularly in relation to the ritual art that is central to his argument. Focusing on Gell's employment of Peirce's term 'index' (out of his triad of index, icon, and symbol), I note that Peirce's approach deflects attention from signification towards the link between art works and the things to which they refer. I consider what Peirce meant by abduction, and conclude that while Gell makes a good case for the agency of art objects he does not explain the distinctive ways in which art objects extend their maker's or user's agency. Gell lacked the time to make detailed revisions before publication and I acknowledge that, given more time, he might have revised some parts of the book. 相似文献
58.
TNF inhibitors are currently considered both effective and cost-effective in patients with active rheumatoid arthritis (RA),
particularly in patients who have not responded fully to methotrexate. There is substantial doubt about the cost-effectiveness
of TNF inhibitors as initial treatment for active RA. New data from the National Data Bank for Rheumatic Diseases now question
the current consensus in methotrexate failures. The data suggest that in routine clinical practice TNF inhibitors provide
only modest incremental benefits over best conventional therapy. If confirmed, these observational studies suggest that the
economic argument underpinning the widespread use of TNF inhibitors in established RA is unsustainable. 相似文献
59.
Background
DNA Microarrays have become the standard method for large scale analyses of gene expression and epigenomics. The increasing complexity and inherent noisiness of the generated data makes visual data exploration ever more important. Fast deployment of new methods as well as a combination of predefined, easy to apply methods with programmer's access to the data are important requirements for any analysis framework. Mayday is an open source platform with emphasis on visual data exploration and analysis. Many built-in methods for clustering, machine learning and classification are provided for dissecting complex datasets. Plugins can easily be written to extend Mayday's functionality in a large number of ways. As Java program, Mayday is platform-independent and can be used as Java WebStart application without any installation. Mayday can import data from several file formats, database connectivity is included for efficient data organization. Numerous interactive visualization tools, including box plots, profile plots, principal component plots and a heatmap are available, can be enhanced with metadata and exported as publication quality vector files. 相似文献60.