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1.
Edda Tobiasch Hermelita Winter Jürgen Schweizer 《Differentiation; research in biological diversity》1992,50(3):163-178
In the course of studies on local keratin phenotypes in the epidermis of the adult mouse, we have identified a new 65 kD and 48 kD keratin pair. In mouse skin, this keratin pair is only expressed in suprabasal cells of adult mouse tail scale epidermis which is characterized by the complete absence of a granular layer and the formation of a remarkably compact stratum corneum. A second site in which the 65 kD and 48 kD keratin pair is suprabasally expressed and whose morphology corresponds to that of tail scale epidermis is found in the posterior unit of the complex filiform papillae of mouse tongue. The causal relationship of the expression of the 65 kD and 48 kD keratins with this particular type of a non-pathological epithelial parakeratosis is emphasized by the suppression of the mRNA synthesis of the two keratins during retinoic acid mediated orthokeratotic conversion of tail scale epidermis. Apart from tail scale epidermis and the posterior unit of the filiform papillae, the 65 kD and 48 kD keratin pair is, however, also coexpressed with "hard" alpha keratins in suprabulbar cells of hair follicles and in suprabasal cells of the central core unit of the lingual filiform papillae. The non alpha-helical domains of the two new keratins are rich in cysteine and proline residues and lack the typical subdomains into which epithelial keratins of both types can be divided. This structural resemblance of the 65 kD and 48 kD keratins to "hard" alpha keratins is supported by comparative flexibility predictions for their non alpha-helical domains. Phylogenetic investigations then show that the 65 kD and 48 kD keratin pair has evolved together with hair keratins, but has diverged from these during evolution to constitute an independent branch of a pair of hair-related keratins. In view of this exceptional position of the 65 kD and 48 kD keratins within the keratin multigene family, their expression has apparently been adopted by rare anatomical sites in which an orthokeratinized stratum corneum would be too soft and a hard keratinized structure would be too rigid to meet the functional requirement of the respective epithelia. 相似文献
2.
Andrej Anokhin Ortrud Steinlein Christine Fischer Yiping Mao Peter Vogt Edda Schalt Friedrich Vogel 《Human genetics》1992,90(1-2):99-112
Summary The studied phenotype, the low-voltage electroencephalogram (LVEEG), is characterized by the absence of an alpha rhythm from the resting EEG. In previous studies, evidence was found for a simple autosomal-dominant mode of inheritance of the LVEEG. Such a polymorphism in brain function can be used as a research model for the stepwise elucidation of the molecular mechanism involved in those aspects of neuronal activity that are reflected in the EEG. Linkage with the variable number of tandem repeats (VNTR) marker CMM6 (D20S19) and localization of an LVEEG (EEGV1) gene on 20q have previously been reported, and genetic heterogeneity has been demonstrated. This latter result has been corroborated by studing new marker (MS214). The phenotype of the LVEEG is described here in greater detail. Its main characteristic is the absence of rhythmic alpha activity, especially in occipital leads, whereas other wave forms such as beta or theta waves may be present. Analysis of 17 new families (some of them large), together with 60 previously described nuclear families, supports the genetic hypothesis of an autosomal-dominant mode of inheritance. Problems connected with the analysis of linkage heterogeneity, exclusion mapping, and the study of multipoint linkage are discussed. A possible explanation of the localization of LVEEG in the close vicinity of another gene influencing synchronization of the normal EEG, the gene for benign neonatal epilepsie, is given. 相似文献
3.
Edda De Rossi Giovanna Riccardi Anna Maria Sanangelantoni Orio Ciferri 《FEMS microbiology letters》1985,30(1-2):239-244
Abstract A Spirulina platensis gene library has been constructed using cosmid vector pMMB34. The cosmid bank was controlled for its random gene distribution by colony hybridization. Genes were identified using either homologous or heterologous probes of genes involved in photosynthesis (large and small subunit of d -ribulose 1,5-bisphosphate carboxylase, 32 kDa thylakoid protein, α, β subunits of C-phycocyanin) and protein synthesis (elongation factors EF-Tu, EF-G). 相似文献
4.
E. Schneider W. Frotscher H. Tielecke W. Bollmann 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1960,30(6):254-258
Ohne ZusammenfassungMit 2 Abbildungen 相似文献
5.
The preparation and X-ray structure of [Ag(9-EtGH-N7)2]NO3·H2O(9-EtGH=neutral 9-ethylguanine) is reported. The compound crystallizes in the triclinic system, space group P
with a=7.063(6), b=7.153(3), c=11.306(10) Å, α=83.36(6), β=76.66(7), γ=81.44(6)°. The cation is centrosymmetric with Ag(I) coordinated via two N7 positions and Ag---N7 bond lengths of 2.11(1) Å. Applying 109Ag NMR spectroscopy, complex formation constants for both the 1:1 complex (log β1=0.6) and the title compound (log β2=1.6) in Me2SO have been determined. 相似文献
6.
Leirla Salazar Hafida Fsihi Edda de Rossi Giovanna Riccardi Carmen Rios Stewart T. Cole Howard E. Takiff 《Molecular microbiology》1996,20(2):283-293
The genus Mycobacterium is composed of species with widely differing growth rates ranging from approximately three hours in Mycobacterium smegmatis to two weeks in Mycobacterium leprae. As DNA replication is coupled to cell duplication, it may be regulated by common mechanisms. The chromosomal regions surrounding the origins of DNA replication from M. smegmatis, M. tuberculosis, and M. leprae have been sequenced, and show very few differences. The gene order, rnpA-rpmH-dnaA-dnaN-recF-orf-gyrB-gyrA, is the same as in other Gram-positive organisms. Although the general organization in M. smegmatis is very similar to that of Streptomyces spp., a closely related genus, M. tuberculosis and M. leprae differ as they lack an open reading frame, between dnaN and recF, which is similar to the gnd gene of Escherichia coli. Within the three mycobacterial species, there is extensive sequence conservation in the intergenic regions flanking dnaA, but more variation from the consensus DnaA box sequence was seen than in other bacteria. By means of subcloning experiments, the putative chromosomal origin of replication of M. smegmatis, containing the dnaA-dnaN region, was shown to promote autonomous replication in M. smegmatis, unlike the corresponding regions from M. tuberculosis or M. leprae. 相似文献
7.
Ulf Büntgen Andrew Liebhold Hannes Jenny Atle Mysterud Simon Egli Daniel Nievergelt Nils C. Stenseth Kurt Bollmann 《Ecology letters》2014,17(3):303-313
Direct effects of climate change on animal physiology, and indirect impacts from disruption of seasonal synchrony and breakdown of trophic interactions are particularly severe in Arctic and Alpine ecosystems. Unravelling biotic from abiotic drivers, however, remains challenging because high‐resolution animal population data are often limited in space and time. Here, we show that variation in annual horn growth (an indirect proxy for individual performance) of 8043 male Alpine ibex (Capra ibex) over the past four decades is well synchronised among eight disjunct colonies in the eastern Swiss Alps. Elevated March to May temperatures, causing premature melting of Alpine snowcover, earlier plant phenology and subsequent improvement of ibex food resources, fuelled annual horn growth. These results reveal dependency of local trophic interactions on large‐scale climate dynamics, and provide evidence that declining herbivore performance is not a universal response to global warming even for high‐altitude populations that are also harvested. 相似文献
8.
Kurt Reifenberg Fei Cheng Laura Twardowski Ines Küpper Elena Wiese Franziska Bollmann Hartmut Kleinert Manfred Blessing Karl J. Lackner Michael Torzewski 《PloS one》2013,8(12)
Clinical data have indicated a negative correlation between plasma TGFß1 concentrations and the extent of atherosclerosis and have thus led to the hypothesis that the pleiotropic cytokine may have anti-atherogenic properties. T-cells are currently discussed to significantly participate in atherogenesis, but the precise role of adaptive immunity in atherogenesis remains to be elucidated. TGFß1 is known to strongly modulate the function of T-cells, however, inhibition of TGFß1 signalling in T-cells of atherosclerosis-prone knock-out mice failed to unequivocally clarify the role of the cytokine for the development of atherosclerosis. In the present study, we thus tried to specify the role of TGFß1 in atherogenesis by using the murine CD2-TGFß1 transgenic strain which represents a well characterized model of T-cell specific TGFß1 overexpression. The CD2-TGFß1 transgenic mice were crossed to ApoE knock-out mice and quantity and quality of atherosclerosis regarding number of macrophages, smooth muscle cells, CD3 positive T-cells and collagen was analyzed in CD2-TGFß1 ApoE double mutants as well as non-transgenic ApoE controls on both normal and atherogenic diet of a duration of 8, 16 or 24 weeks, respectively. In all experimental groups investigated, we failed to detect any influence of TGFß1 overexpression on disease. Total number of CD3-positive T-lymphocytes was not significantly different in atherosclerotic lesions of CD2-TGFß1 ApoE−/− females and isogenic ApoE−/− controls, even after 24 weeks on the atherogenic diet. The synopsis of these data and our previous study on TGFß1 overexpressing macrophages suggests that potential effects of TGFß1 on atherosclerosis are most probably mediated by macrophages rather than T-cells. 相似文献
9.
10.
Agnès Fleury Esperanza Garcia Marisela Hernández Roger Carrillo Tzipe Govezensky Gladis Fragoso Edda Sciutto Leslie J. S. Harrison R. Michael Evans Parkhouse 《PLoS neglected tropical diseases》2013,7(3)