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Daniel Hohl Barbara Ruf Olano Pierre A. de Viragh Marcel Huber Carol J. Detrisac Urs W. Schnyder Dennis R. Roop 《Differentiation; research in biological diversity》1993,54(3):25-34
Abstract. In this study we analyzed the expression patterns of loricrin in various species and tissues using immunohistochemistry, immunoblotting and Northern blots. Loricrin is a glycine-, serine- and cysteine-rich protein expressed very late in epidermal differentiation in the granular layers of normal mouse and human epidermis. Later on in differentiation, loricrin becomes cross-linked as a major component into the cornified cell envelope by the formation of Nɛ -(γ-glutamyl)lysine isopeptide bonds. This process either occurs directly or by the intermediate accumulation in L-keratohyaline granules of mouse epidermis and human acrosyringia. Loricrin was identified in all mammalian species analyzed by virtue of its highly conserved carboxy-terminal sequences revealing an electric mobility of ∼60 kDa in rodents, rabbit and cow and of ∼35 kDa in lamb and human on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Loricrin is expressed in the granular layer of all mammalian orthokeratinizing epithelia tested including oral, esophageal and fore-stomach mucosa of rodents, tracheal squamous metaplasia of vitamin A deficient hamster and estrogen induced squamous vaginal epithelium of ovary ectomized rats. Loricrin is also expressed in a few parakeratinizing epithelia such as BBN [N-butyl-N-(4–hydroxybutyl)nitrosamine]-induced murine bladder carcinoma and a restricted subset of oral and single vaginal epithelial cells in higher mammals. Our results provide further evidence that the program of squamous differentiation in internal epithelia of the upper alimentary tract in rodents and higher mammals differ remarkably. In addition, we also have noted the distinct distribution patterns of human loricrin and involucrin, another major precursor protein of the cornified cell envelope. 相似文献
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A computer-aided search for potential ribosome recognition sequences of mRNAs from tobacco chloroplasts shows that more than 90% of mRNA species contain sequences upstream of the respective initiator codons, which allow base pairing with 3′-terminal sequences of small subunit rRNA. This complementarity in several cases involves 16 S rRNA sequences between the canonical CCUCC sequence and the 3′-terminal stem/loop structure. The distances between potential ribosome recognition sequences and initiator codons can be up to 25 nucleotides which is much greater when compared to the spacing of 7±2 nucleotides observed for the classical Shine-Dalgarno sequences in bacterial mRNAs. 相似文献
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F Buli?-Jakus N Skreb G Juri?-Leki? A Svajger 《The International journal of developmental biology》1990,34(2):275-279
Rat egg cylinders at the primitive streak stage were grown in modified organ culture for 2 weeks using a chemically-defined medium. The purpose of the experiment was to determine whether the terminal tissue differentiation is modified by human transferrin. The control sets were grown in medium with or without rat serum. In explants treated with transferrin, groups of atypical cells of the ocular lens (lentoids) appeared more frequently than in both control sets; however neuroblasts were observed as often as in the serum-supplemented medium. Bovine serum albumin (BSA) stimulated the differentiation of neuroblasts but did not promote lentoid formation. We conclude that human transferrin does stimulate the differentiation of lentoids in rat embryonic explants, but the mechanism of its action remains unknown. 相似文献
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Anita Shepherd Danny Awty-Carroll Jason Kam Chris Ashman Elena Magenau Enrico Martani Mislav Kontek Andrea Ferrarini Stefano Amaducci Chris Davey Vanja Jurišić Gert-Jan Petrie Mohamad Al Hassan Isabelle Lamy Iris Lewandowski Emmanuel de Maupeou Jon McCalmont Luisa Trindade Kasper van der Cruijsen Philip van der Pluijm Rebecca Rowe Andrew Lovett Iain Donnison Andreas Kiesel John Clifton-Brown Astley Hastings 《Global Change Biology Bioenergy》2023,15(4):444-461
New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020–2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020–2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7–89.7 Mt year−1 biomass, with potential for 1.2–1.3 EJ year−1 energy and 36.3–40.3 Mt year−1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety. 相似文献
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Vsevolod A. Tverdislov Salam El Karadaghi Doris J. Bucher Juri A. Zakomirdin Igor G. Kharitonenkov 《生物化学与生物物理学报:生物膜》1984,778(2):276-280
The dependence of the surface potential difference (ΔU), transversal elasticity module (E1) and membrane conductivity (G0) on the concentrations of the antiviral drugs, rimantadine and amantadine was studied in the planar bilayer lipid membrane system. The method used was based on independent measurements of the second and third harmonics of the membrane capacitance current. The binding constants of bilayer lipid membranes obtained from the drug adsorption isotherms were 2.1 · 105 M?1 and 1.3 · 104 M?1 for rimantadine and amantadine, respectively. The changes in G0 took place only after drug adsorption saturation had been achieved. The influence of rimantadine and amantadine on the interaction of bilayer lipid membranes with matrix protein from influenza virus was also investigated. The presence of 70 μg/ml rimantadine in the bathing solution resulted in an increase in the concentration of M-protein at which the adsorption and conductance changes were observed. The effects of amantadine were similar to those of rimantadine but required a higher critical concentration of amantadine. The results obtained suggest that the antiviral properties of rimantadine and amantadine may be related to the interaction of these drugs with the cell membrane, which can affect virus penetration into the cell as well as maturation of the viral particle at the cell membrane. 相似文献
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