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11.
Deletion analysis of the SUP35 gene of the yeast Saccharomyces cerevisiae reveals two non-overlapping functional regions in the encoded protein 总被引:13,自引:0,他引:13
Michael D. Ter-Avanesyan Vitaly V. Kushnirov Adilya R. Dagkesamanskaya Svetlana A. Didichenko Yury O. Chernoff Sergey G. Inge-Vechtomov Vladimir N. Smirnov 《Molecular microbiology》1993,7(5):683-692
SUP35is an omnipotent suppressor gene of Saccharomyces cerevisiae coding for a protein consisting of a C-terminal part similar to the elongation factor EF-1α and a unique N-terminal sequence of 253 amino acids. Twelve truncated versions of the SUP35 gene were generated by the deletion of fragments internal to the coding sequence. Functional studies of these deletion mutants showed that: (i) only the EF-1α-like C-terminal part of the Sup35 protein is essential for the cell viability; (ii) overexpression of either the N-terminal part of the Sup35 protein or the full-length Sup35 protein decreases translational fidelity, resulting in omnipotent suppression and reduced growth of [psi+] strains; (iii) expression of the C-terminal part of the Sup35 protein generates an antisuppressor phenotype; and (iv) both the N- or C-terminal segments of the Sup35 protein can bind to 80S ribosomes. Thus, the data obtained define two domains within the Sup35 protein which are responsible for different functions. 相似文献
12.
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Andrey A. Rosenkranz Sergey V. Yachmenev David A. Jans Natalya V. Serebryakova Vitaly I. Murav''ev Reiner Peters Alexander S. Sobolev 《Experimental cell research》1992,199(2):323-329
A soluble construct consisting of a plasmid carrying the gene of the SV40 large T-antigen and an insulin-poly-L-lysine conjugate is able to selectively transfect PLC/PRF/5 human hepatoma cells which possess insulin receptors. Transfection can be efficiently competed by excess free insulin. To examine intracellular transport of the construct, it was fluorescently labeled and its accumulation on and in cells visualized by video-enhanced microscopy and quantitative confocal laser scanning microscopy. After 2 h at 37 degrees C, the labeled construct was found predominantly in intracellular acidic compartments, with a substantial portion of fluorescence localized both near and in the cell nucleus. Binding, endocytosis, and nuclear localization of the labeled conjugate could all be competed by excess free insulin, thus indicating that entry of the conjugate into cells was specifically mediated by the insulin receptor. 相似文献
14.
V I Gorbach I N Krasikova P A Lukyanov O Y Razmakhnina T F Solov'eva Y S Ovodov 《European journal of biochemistry》1979,98(1):83-86
Lipid A isolated from lipopolysaccharide of Yersinia pseudotuberculosis was used for immunization of rabbits to afford antisera to lipid A with titers of 1:640 in the passive hemolysis test. Exhaustion of immune serume with sheep erythrocytes decreased antibody titers up to 1:160. Authentic samples of 2-(DL-3-hydroxytetradecanoyl)amino-2-deoxy-D-glucose 6-phosphate, 2-tetradecanoylamino-2-deoxy-D-glucose 6-phosphate and 2-acetamido-2-deoxy-D-glucose 6-phosphate have been synthesized in order to carry out a comparative study of inhibitory activity of these compounds and lipid A using a system of lipid A and antiserum to lipid A. As a result, the immunodominant moiety of the lipid A of Y. pseudotuberculosis proved to contain a D-glucosamine residue acylated with 3-hydroxytetradecanoic acid at the amino group. The nature of the fatty acid acylating the amino group of glucosamine does not play an important role in the structure of immunodominant moiety of lipid A. 相似文献
15.
Bernhard H. J. Juurlink Sergey Fedoroff 《In vitro cellular & developmental biology. Plant》1979,15(2):86-94
Summary Whole mouse embryos were grown in vitro from Theiler stage 12 (1 to 7 somites) to Theiler stages 15 and 16 (25 to 35 somites).
This procedure gives experimental access to precisely staged embryos during the early period of neurogenesis. To follow the
further development of neurons in vitro, fragments of spinal primordia were set up from these cultured embryos. In such cultures,
the proliferation of precursor cells, the formation of postmitotic cells and, finally, the cytodifferentiation of neurons
were observed.
A preliminary account of this work was given at the Tissue Culture Association Meeting in 1977, and the Canadian Federation
of Biological Societies Meeting in 1977 (1,2).
This work was supported by Grant MT 4235 from the Medical Research Council of Canada. 相似文献
16.
A crucial step in several major evolutionary transitions is the division of labor between components of the emerging higher-level evolutionary unit. Examples include the separation of germ and soma in simple multicellular organisms, appearance of multiple cell types and organs in more complex organisms, and emergence of casts in eusocial insects. How the division of labor was achieved in the face of selfishness of lower-level units is controversial. I present a simple mathematical model describing the evolutionary emergence of the division of labor via developmental plasticity starting with a colony of undifferentiated cells and ending with completely differentiated multicellular organisms. I explore how the plausibility and the dynamics of the division of labor depend on its fitness advantage, mutation rate, costs of developmental plasticity, and the colony size. The model shows that the transition to differentiated multicellularity, which has happened many times in the history of life, can be achieved relatively easily. My approach is expandable in a number of directions including the emergence of multiple cell types, complex organs, or casts of eusocial insects. 相似文献
17.
A checklist of identified oribatid mite taxa from riverine freshwater environments from six islands in Polynesia (New Caledonia, Tahiti, Moorea, Rurutu, Tubuai, Raiatea) is presented; 18 species, 16 genera and eight families were recorded. Trhypochthoniellus longisetus (Berlese, 1904) and Trimalaconothrus albulus Hammer, 1972 prevailed on distribution. Fortuynia smiti
sp. n. (Fortuyniidae) is described from New Caledonia. The new speciesis morphologically most similar to Fortuynia marina Hammen, 1960 from New Guinea, but it differs from the latter by the longer notogastral setae dm, lm, c2, p1, epimeral setae 3b and adanal setae ad1 and the presence of prodorsal lateral ridges. 相似文献
18.
19.
Novikova Tatyana I. Asbaganov Sergey V. Ambros Elena V. Zaytseva Yulianna G. 《In vitro cellular & developmental biology. Plant》2020,56(3):307-317
In Vitro Cellular & Developmental Biology - Plant - In order to induce in vitro axillary shoot proliferation from single-node explants of Rhododendron mucronulatum Turcz., two techniques of... 相似文献
20.
Syatkin Sergey P. Neborak Ekaterina V. Khlebnikov Andrei I. Komarova Marina V. Shevkun Natalia A. Kravtsov Eduard G. Blagonravov Mikhail L. Agostinelli Enzo 《Amino acids》2020,52(2):199-211
Amino Acids - The polyamine (PA) metabolism is involved in cell proliferation and differentiation. Increased cellular PA levels are observed in different types of cancers. Products of PA oxidation... 相似文献