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1.
Nevenka Me?trovi? Martina Pavlek Ana Car Philippe Castagnone-Sereno Pierre Abad Miroslav Plohl 《PloS one》2013,8(6)
Tandemly arrayed non-coding sequences or satellite DNAs (satDNAs) are rapidly evolving segments of eukaryotic genomes, including the centromere, and may raise a genetic barrier that leads to speciation. However, determinants and mechanisms of satDNA sequence dynamics are only partially understood. Sequence analyses of a library of five satDNAs common to the root-knot nematodes Meloidogyne chitwoodi and M. fallax together with a satDNA, which is specific for M. chitwoodi only revealed low sequence identity (32–64%) among them. However, despite sequence differences, two conserved motifs were recovered. One of them turned out to be highly similar to the CENP-B box of human alpha satDNA, identical in 10–12 out of 17 nucleotides. In addition, organization of nematode satDNAs was comparable to that found in alpha satDNA of human and primates, characterized by monomers concurrently arranged in simple and higher-order repeat (HOR) arrays. In contrast to alpha satDNA, phylogenetic clustering of nematode satDNA monomers extracted either from simple or from HOR array indicated frequent shuffling between these two organizational forms. Comparison of homogeneous simple arrays and complex HORs composed of different satDNAs, enabled, for the first time, the identification of conserved motifs as obligatory components of monomer junctions. This observation highlights the role of short motifs in rearrangements, even among highly divergent sequences. Two mechanisms are proposed to be involved in this process, i.e., putative transposition-related cut-and-paste insertions and/or illegitimate recombination. Possibility for involvement of the nematode CENP-B box-like sequence in the transposition-related mechanism and together with previously established similarity of the human CENP-B protein and pogo-like transposases implicate a novel role of the CENP-B box and related sequence motifs in addition to the known function in centromere protein binding. 相似文献
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Tetanus Toxin and Botulinum A and C Neurotoxins Inhibit Noradrenaline Release from Cultured Mouse Brain 总被引:4,自引:3,他引:1
The specific binding protein for substance P (SP) was solubilized in an active form from the crude mitochondrial (P2) fraction of bovine brainstem. After incubation with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS) and 0.1 M NaCl at 0 degrees C for 30 min, the SP binding to the supernatant fraction (100,000 g, 60 min) was determined by the glass fiber filtration method reported by Bruns et al. (1983). The specific [3H]SP binding to the solubilized fraction was highly specific for SP and was displaced by nanomolar concentrations of SP and physalaemin, but only by micromolar concentrations of eledoisin. In addition, the binding was inhibited by GTP (approximately 40% of the specific binding decreased by 10 microM GTP) in both preparations. These results were virtually identical to those of P2 membrane preparations and suggested that this high-affinity SP binding site belongs to the SP-P type. Scatchard analyses of SP binding to the solubilized fraction revealed a single saturable component with a Bmax of 22.0 +/- 5.10 fmol/mg protein and a KD of 0.79 nM, and these values are almost the same as those obtained in the P2 fraction (Bmax = 31.3 +/- 3.56 fmol/mg protein, KD = 0.82 nM). Gel filtration analysis showed that the detergent-SP binding protein complex has two calculated molecular weights of greater than 1,000,000 and 55,000-60,000 (a corresponding Stokes radius of 35.5 nm). 相似文献
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Stress and Age Related Spots with Immunoreactivity to Ubiquitin-Antibody at Protoplast Surfaces 总被引:2,自引:0,他引:2
Schulz Margot; Janssen Martina; Knop Mona; Schnabl Heide 《Plant & cell physiology》1994,35(4):551-556
Mesophyll protoplasts from primary leaves of 2, 3, and 4 weekold Viciafaba L. plants and from not expanded leaves of 2 weekold plants were incubated with rabbit anti-ubiquitin antibodyand FITC labeled goat anti-rabbit IgG. Dependent on age of theplant material, an increase in size and number of immunoreactivespots at protoplast surfaces were observed, when incubationswere performed after 16 h storage to allow protoplast to recover.A relationship between isolation stress and the intensity ofimmunolabeling was demonstrated for protoplasts from not expandedleaves. Furthermore, the surface of isolation stressed protoplastsshowed an increasing number of immunoreactive spots when plantswere previously exposed to water deficiency conditions for 1,2 or 4 days. Water deficiency conditions and isolation stressare therefore thought to induce ubiquitination of surface locatedproteins. A phenomenon, which seemed to be normally correlatedwith early events of senescence. (Received October 28, 1993; Accepted February 21, 1994) 相似文献
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Filamentous algae in eutrophic carp ponds in South Bohemia (Central Europe) were studied from 1988 to 1990. High biomass (490 g DW m-2) was attained by Cladophora fracta (O. F. Müll. ex Vahl) Kütz. after two months of growth. This marked growth depleted inorganic carbon in the water, but did not decrease the concentration of tissue nutrients. Laboratory measurements of final pH indicate that all the filamentous algae studied, except for Tribonema, are very efficient HCO3
- users. An extremely high pH of 11.6 and oxygen concentration of 32 mg l-1 were measured in the algal mats. High pH resulted in CaCO3 precipitation, visible as white incrustations on algal filaments. The amount of precipitated CaCO3 reached 134 kg ha-1. After reaching peak biomass, 90% of the Cladophora decomposed over the next 95 days.The highest net photosynthetic rate in C. fracta was measured between pH range 8.5–10.0 and oxygen concentrations of 7–12 mg l-1. Optimum temperature for photosynthesis was between 17–22°C. 相似文献
8.
Riccardo Fedeli Andrea Vannini Martina Grattacaso Stefano Loppi 《The Annals of applied biology》2023,183(2):135-140
Potato is the fourth most widely consumed staple food in the world. This study investigated the effectiveness of 0.2% wood distillate (WD), a biostimulant derived from the pyrolysis of waste plant biomass, in boosting the nutritional quality of potato tubers. The results showed that application of WD significantly increased the content of soluble sugars (sucrose +56.3%; glucose +44.9%; fructose +62.2%), starch (+35.1%) and total carbohydrates (+16.8%). Antioxidants (total antioxidant power, polyphenols, flavonoids) and most mineral elements (K, Mg, Ca, Na, Fe, Zn) were not affected. A lower content of Cu (−17.8%) and P (−24.5%) was found in WD-treated potato. 相似文献
9.
Research data management (RDM) requires standards, policies, and guidelines. Findable, accessible, interoperable, and reusable (FAIR) data management is critical for sustainable research. Therefore, collaborative approaches for managing FAIR-structured data are becoming increasingly important for long-term, sustainable RDM. However, they are rather hesitantly applied in bioengineering. One of the reasons may be found in the interdisciplinary character of the research field. In addition, bioengineering as application of principles of biology and tools of process engineering, often have to meet different criteria. In consequence, RDM is complicated by the fact that researchers from different scientific institutions must meet the criteria of their home institution, which can lead to additional conflicts. Therefore, centrally provided general repositories implementing a collaborative approach that enables data storage from the outset In a biotechnology research network with over 20 tandem projects, it was demonstrated how FAIR-RDM can be implemented through a collaborative approach and the use of a data structure. In addition, the importance of a structure within a repository was demonstrated to keep biotechnology research data available throughout the entire data lifecycle. Furthermore, the biotechnology research network highlighted the importance of a structure within a repository to keep research data available throughout the entire data lifecycle. 相似文献
10.
Melissa Pederson Mussell Carol B. Peterson Christine L. Weller Ross D. Crosby Martina de Zwaan James E. Mitchell 《Obesity (Silver Spring, Md.)》1996,4(5):431-439
Obese individuals with binge eating disorder (BED) differ from obese non-binge eating (NBE) individuals in a number of clinically relevant ways. This study examined attitudinal responses to various measures of body image in women seeking obesity treatment, by comparing NBE participants (n=80) to those with BED (n=48). It was hypothesized that women with BED would demonstrate greater attitudinal disturbance of body image compared to NBE individuals. It was further hypothesized that significant differences between groups would remain after statistically controlling for degree of depression. Consistent with the primary hypothesis, BED participants reported significantly increased attitudinal disturbance in body dissatisfaction and size perception compared to NBE participants. Although shared variance was observed between measures of depression and body image on some items, several aspects of increased body image disturbance remained after statistically controlling for depression. Treatment implications and recommendations for future research are discussed. 相似文献