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121.
Tomasz Downarowicz Dante Travisany Martin Montecino Alejandro Maass 《Acta biotheoretica》2014,62(2):145-169
A genome of a living organism consists of a long string of symbols over a finite alphabet carrying critical information for the organism. This includes its ability to control post natal growth, homeostasis, adaptation to changes in the surrounding environment, or to biochemically respond at the cellular level to various specific regulatory signals. In this sense, a genome represents a symbolic encoding of a highly organized system of information whose functioning may be revealed as a natural multilayer structure in terms of complexity and prominence. In this paper we use the mathematical theory of symbolic extensions as a framework to shed light onto how this multilayer organization is reflected in the symbolic coding of the genome. The distribution of data in an element of a standard symbolic extension of a dynamical system has a specific form: the symbolic sequence is divided into several subsequences (which we call layers) encoding the dynamics on various “scales”. We propose that a similar structure resides within the genomes, building our analogy on some of the most recent findings in the field of regulation of genomic DNA functioning. 相似文献
122.
Antonello Mai Dante Rotili Domenico Tarantino Angela Nebbioso Sabrina Castellano Gianluca Sbardella Marc Tini Lucia Altucci 《Bioorganic & medicinal chemistry letters》2009,19(4):1132-1135
We identified a series of 4-hydroxyquinolines bearing a C1 to C15 alkyl chain at the C2 position and a carbethoxy/carboxy group at the C3 position of the quinoline nucleus (MC compounds), endowed with selective inhibitory activity against the p300/CBP HAT enzymes. Enzyme inhibition was investigated using in vitro HAT assays and by western blot analysis of cellular lysates to examine the acetylation levels of histone H3 and α-tubulin. When tested in U937 cells, some compounds displayed pro-apoptotic or cytodifferentiating properties. 相似文献
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Kessner D Kiselev MA Hauss T Dante S Wartewig S Neubert RH 《European biophysics journal : EBJ》2008,37(6):1051-1057
This letter presents our first results in using the benefit of selective deuteration in neutron diffraction studies on stratum
corneum (SC) lipid model systems. The SC represents the outermost layer of the mammalian skin and exhibits the main skin barrier.
It is essential for studying drug penetration through the SC to know the internal structure and hydration behaviour on the
molecular level. The SC intercellular matrix is mainly formed by ceramides (CER), cholesterol (CHOL) and long- chain free
fatty acids (FFA). Among them, CHOL is the most abundant individual lipid, but a detailed knowledge about its localisation
in the SC lipid matrix is still lacking. The structure of the quaternary SC lipid model membranes composed of either CER[AP]/CHOL-D6/palmitic
acid (PA)/cholesterol sulphate (ChS) or CER[AP]/CHOL-D7/PA/ChS is characterized by neutron diffraction. Neutron diffraction
patterns from the oriented samples are collected at the V1 diffractometer of the Hahn-Meitner-Institute, Berlin, measured
at 32°C, 60% humidity and at different D2O contents. The neutron scattering length density profile in the direction normal to the surface is restored by Fourier synthesis
from the experimental diffraction patterns. The analysis of scattering length density profile is a suitable tool for investigating
the internal structure of the SC lipid model membranes. The major finding is the experimental proof of the CHOL localisation
in SC model membrane by deuterium labelling at prominent positions in the CHOL molecules. 相似文献
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126.
Beta-amyloid 25 to 35 is intercalated in anionic and zwitterionic lipid membranes to different extents 下载免费PDF全文
D96N bacteriorhodopsin has two photointermediates with the deprotonated Schiff base: the M and MN intermediates. We measure the time-resolved x-ray diffraction of the D96N purple membrane after flash photoexcitation (pH 7.0, 25 degrees C). The data clearly show the M-MN transition during the D96N photocycle. Low-resolution projection maps of these states show that the F helix of the MN intermediate shifts from its original position and this shift is much larger than that of the M intermediate. This indicates that the F helix moves in the M-MN transition of the D96N bacteriorhodopsin photocycle. Moreover, the existence of the MN intermediate in the D96N photocycle under neutral pH indicates that the MN intermediate is not peculiar to the alkaline condition. It is notable that the structural transition of M-MN is independent of the protonation state of the Schiff base. Therefore, the F helix movement precedes reprotonation of the Schiff base in the bacteriorhodopsin photocycle. Our previous study showed that the M-MN transition is hydration-dependent and that the MN intermediate is more hydrated than the M intermediate. Considering this together with the present results, we conclude that the movement of the F helix causes hydration of the cytoplasmic side, which promotes the reprotonation of the Schiff base. 相似文献
127.
Vissio PG Andreone L Paz DA Maggese MC Somoza GM Strüssmann CA 《The Journal of experimental zoology》2002,293(5):492-499
The aim of this study was to analyze the relationship between somatolactin (SL) expressing cells and the reproductive status in a multiple spawning fish, the pejerrey Odontesthes bonariensis. Somatolactin cells were identified in adults of both sexes by immunocytochemistry using a heterologous piscine antiserum. The area of the cells that showed immunoreactivity to SL (ir-SL) was compared in specimens with different degrees of reproductive activity as inferred from histological examination of the gonads and calculation of the gonadosomatic index (GSI %). The results showed a significant difference between the area of ir-SL cells of resting/regressing (62.9 +/- 2.1 micron 2) and sexually active/vitellogenic (76.8 +/- 2.3 micron 2) females and a significant positive correlation between the ir-SL cellular area and the GSI % (P < 0.01 in both cases). In males, the correlation between the area of ir-SL cells and the GSI % was not statistically significant. However, in those animals with the highest GSI % values, the ir-SL cells appeared more numerous and showed an increase in the immunostained area when compared to individuals with lower GSI % values. The present in morphological observations are in accordance with biochemical data obtained from other species and support the assumption that SL might be involved in the regulation of reproduction in fish. 相似文献
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Theresa?M.?LeeEmail author Noah?M.?Ivers Paul?Dorian Liisa?Jaakkimainen Dan?Legge Dante?Morra Alissia?Valentinis Laura?Wing Jacqueline?Young Karen?Tu 《Implementation science : IS》2015,11(1):159