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21.
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
22.
Cascade J. B. Sorte Ron J. Etter Robert Spackman Elizabeth E. Boyle Robyn E. Hannigan 《PloS one》2013,8(11)
As the climate warms, species that cannot tolerate changing conditions will only persist if they undergo range shifts. Redistribution ability may be particularly variable for benthic marine species that disperse as pelagic larvae in ocean currents. The blue mussel, Mytilus edulis, has recently experienced a warming-related range contraction in the southeastern USA and may face limitations to northward range shifts within the Gulf of Maine where dominant coastal currents flow southward. Thus, blue mussels might be especially vulnerable to warming, and understanding dispersal patterns is crucial given the species'' relatively long planktonic larval period (>1 month). To determine whether trace elemental “fingerprints” incorporated in mussel shells could be used to identify population sources (i.e. collection locations), we assessed the geographic variation in shell chemistry of blue mussels collected from seven populations between Cape Cod, Massachusetts and northern Maine. Across this ∼500 km of coastline, we were able to successfully predict population sources for over two-thirds of juvenile individuals, with almost 80% of juveniles classified within one site of their collection location and 97% correctly classified to region. These results indicate that significant differences in elemental signatures of mussel shells exist between open-coast sites separated by ∼50 km throughout the Gulf of Maine. Our findings suggest that elemental “fingerprinting” is a promising approach for predicting redistribution potential of the blue mussel, an ecologically and economically important species in the region. 相似文献
23.
Robert Blake II Elizabeth A. Shute James Waskovsky Arthur P. Harrison JR. 《Geomicrobiology journal》2013,30(3-4):173-192
Abstract Microorganisms capable of aerobic respiration on ferrous ions are spread throughout eubacterial and archaebacterial phyla. Phylogenetically distinct organisms were shown to express spectrally distinct redox‐active biomolecules during autotrophic growth on soluble iron. A new iron‐oxidizing eubacterium, designated as strain Funis, was investigated. Strain Funis was judged to be different from other known iron‐oxidizing bacteria on the bases of comparative lipid analyses, 16S rRNA sequence analyses, and cytochrome composition studies. When grown autotrophically on ferrous ions, Funis produced conspicuous levels of a novel acid‐stable, acid‐soluble yellow cytochrome with a distinctive absorbance peak at 579 nm in the reduced state. Stopped‐flow spectrophotometric kinetic studies were conducted on respiratory chain components isolated from cell‐free extracts of Thiobacillus ferrooxidans. Experimental results were consistent with a model where the primary oxidant of ferrous ions is a highly aggregated c‐type cytochrome that then reduces the periplasmic rusticyanin. The Fe(II)‐dependent, cytochrome c‐catalyzed reduction of the rusticyanin possessed three kinetic properties in common with corresponding intact cells that respire on iron: the same anion specificity, a similar dependence of the rate on the concentration of ferrous ions, and similar rates at saturating concentrations of ferrous ions 相似文献
24.
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
25.
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
26.
The natural aversion of rats to ethanol was overcome by subjecting rats to immobilization stress for a two-week period during which increasing concentrations of ethanol were offered in the drinking water. The rats subjected to this regimen consumed 47% of total calories as ethanol, indefinitely, following removal of the stress. Ethanol was consumed at a rate of 17.1 g/kg body weight along with sufficient stock diet to assure adequate nutrition in the absence of ethanol. 相似文献
27.
Ferdinand Bohlmann Elena Tsankova Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1983,22(2):557-560
The investigation of Encelia canescens afforded, in addition to several known compounds, four new dimeric p-hydroxyacetophenone derivatives, two epimeric chromene dimers and two epimeric mixed dimers of euparin and encecalin. Furthermore, derivatives of tremetone and of encecalin were present. The structures were elucidated hy high field 1H NMR spectroscopy. 相似文献
28.
29.
Use of ATP bioluminescence measurements for the estimation of biomass during biological humification
Summary The development of the microflora during the humification of grape pulp has been investigated by the determination of ATP using the bioluminescence technique. Several extraction methods were tested including the use of dimethylsulphoxide, trichloroacetic acid, grinding and ultrasonification. Dimethylsulphoxide and ultrasonification for 15 sec appeared to be the most effective. The ATP extract was stabilized when it was mixed with 0.75 mM glycine, 4.4 mM Mg-EDTA, pH 7.5 and frozen. The relative error of the ATP assay by bioluminescence did not exceed 6.5%. This method allowed us to show that at least five distinct reproducible microbial phases exist during grape pulp humification. These results show that the microbial biomass changes noticeably and at distinct times during composting. 相似文献
30.