Andrzej Kowalski

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In our previous work (J. Palyga, Genetic polymorphisms of histone H1. b in duck erythrocytes. Hereditas 114, 85-89, 1991) we reported a genetic polymorphism of duck erythrocyte histone H1.b. Here, we screened H1 preparations in a two-dimensional polyacrylamide gel to refine the distribution of allelic forms of H1.b in fifteen duck populations. We have(More)
The general patterns of histone H1 proteins from erythrocyte nuclei of Muscovy duck individuals were similar to those of Pekin type ducks both in acetic acid-urea and 2D polyacrylamide gels. We show here that Muscovy duck histone H1.z in the tested population was represented by three different electromorphs, each presumably encoded by a distinct allelic(More)
Chromatin has a tendency to shift from a relatively decondensed (active) to condensed (inactive) state during cell differentiation due to interactions of specific architectural and/or regulatory proteins with DNA. A promotion of chromatin folding in terminally differentiated avian blood cells requires the presence of either histone H5 in erythrocytes or(More)
Two allelic isoforms (H1.a1 and H1.a2) of histone H1.a were identified within two conservative flocks (R11 and R55) of Rhode Island Red chickens. These proteins form three phenotypes: a1, a2 and a1a2. Birds with phenotype a1 were most common (frequency 0.825-0.980) while the a1a2 chickens appeared relatively rarely (0.017-0.175). The third phenotype a2, not(More)
Knowledge representation has been idenfied as the most important issue facing the field of AI and Law.1 The nature of legal reasoning and decision making, in particular the way judges decide hard cases, have been important jurisprudential issues for many years. it is inescapable that a Iegaf expert system which attempts to emulate the reasoning processes of(More)
Two allelic electromorphs a and b of chicken erythrocyte histone H5 have been detected in a sodium dodecyl sulfate polyacrylamide gel. In an acid-urea gel, however, each of the allelic variants was found to be accompanied by a slower migrating form. A comparison of alpha-chymotrypsin-digested products of H5.a and H5.b revealed that they differed in(More)
Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) is a powerful technique used for separation, detection and quantification of complex protein mixtures expressed within cellular systems. Whereas a single-dimension electrophoretic separation allows to detect individual proteins in cell extracts mainly based on a single physicochemical parameter(More)
In each eukaryotic cell ® ve classes of histones are found. Four of them (H2A, H2B, H3, and H4) play a key role in the organization of the nucleosome core. These proteins are evolutionarily conserved, in contrast to histone H1, which has been reported to vary in its structure within cells, tissues, individuals, and species (Køyszejko-Stefanowicz et al.,(More)
Three different phenotypes of erythrocyte histone H1.z were detected in several lines of duck by using two-dimensional PAGE. Electrophoresis and inheritance data have shown that two co-dominant alleles, z1 and z2, encode two proteins which differ slightly in their apparent molecular masses. Allele z1 was very abundant and was found at a frequency at least(More)
Members of histone H1 family bind to nucleosomal and linker DNA to assist in stabilization of higher-order chromatin structures. Moreover, histone H1 is involved in regulation of a variety of cellular processes by interactions with cytosolic and nuclear proteins. Histone H1, composed of a series of subtypes encoded by distinct genes, is usually(More)