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1

New approaches to the mapping of chromosomal domains

100%

Filipski J., Svetlova E., Avril-Fournout N., Deschavanne P., Bellis M.

Acta Biochimica Polonica

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1996

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tom 43

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nr 2

Although it is generally accepted that the chromosome is divided into elementary subunits/ the structural and functional domains/ the organisation of these structures at the molecuJar level is not well understood. In particular, the domain boundaries are not easily identifiable. Several possible candidates such as MARs/SARs, insulators, LCRs, palindromic sequences, or easily melting sequences have been found in the regions having properties one would except for boundaries. None of these elements, however, has been found in all of the constructs functioning as boundaries in tests in vivo. Recent work suggests that the common denominator might be the presence of GC-rich oligonucleotide streches and the formation of the chromatin hypersensitive sites. A model is discussed in which "unusual" structures, in particular the four-stranded DNA sequence elements containing unpaired bases, play the role of domain boundaries.

2

SARs on an 835 kb DNA fragment from the Drosophila genome

100%

Miassod R., Jullien N.

Acta Biochimica Polonica

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1995

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tom 42

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nr 2

We have investigated the loop organization of a 835 kilobases DNA fragment from the Drosophila genome. This analysis has focused on the perodicity of the distribution of anchoring sequences (SARs) and its relationship to the distribution of A,T-rich regions, transcription units, repeated elements, putative replication origins and topoisomerase II cleavege sites. Altogether, the data support the idea of an active participation of SARs to the structural organization and functioning of this eukaryotic genome.

3

Interaction of the Pisum sativum nuclear matrix proteins with SAR DNA

100%

Rzepecki R., Markiewicz E., Adamiec R., Szopa J.

Acta Biochimica Polonica

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1995

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tom 42

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nr 1

We have isolated the nuclear matrices from Pisum sativum cell nuclei using three methods: i. standard procedure involving extraction of cell nuclei with 2 M NaCl and 1% Triton X-100; ii. the same with pretreatment of cell nuclei with 0.5 mM CuS04 (stabilisation step); and iii. method including lithium diiodosalicylate extraction. We compared the polypeptide pattern and residual DNA content of the nuclear matrices isolated. The nuclear matrices displayed a specific endonuclease activity which was due to the presence of a 32 kDa protein. The isolated nuclear matrices bound specifically the scaffold-attached (SAR) DNA derived from human p interferon gene, in the exogenous SAR binding assay. Using the DNA-protein binding blot assay we demonstrated the presence of two nuclear matrix proteins of 66 kDa and 62 kDa which bound specifically SAR DNA.

4

Effect of nuclear matrix attachment regions on transgene expression in tobacco plants

100%

Nowak W., Gawlowska M., Jarmolowski A., Augustyniak J.

Acta Biochimica Polonica

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2001

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tom 48

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nr 3

Matrix attachment regions (MARs) are thought to participate in the organization and segregation of independent chromosomal loop domains. Although there are several reports on the action of natural MARs in the context of heterologous genes in transgenic plants, in our study we tested a synthetic MAR (sMAR) with the special property of unpairing when under superhelical strain, for its effect on reporter gene expression in tobacco plants. The synthetic MAR was a multimer of a short sequence from the MAR 3 end of the immunoglobulin heavy chain (IgH) enhancer. This sMAR sequence was used to flank the β-glucuronidase (GUS) reporter gene within the T-DNA of the binary vector pBI121. Vectors with or without the sMARs were then used to transform tobacco plants by Agrobacterium tumefaciens. Transgenic plants containing the sMAR sequences flanking the GUS gene exhibited higher levels of transgene expression compared with transgenic plants which lacked the sMARs. This effect was observed independently of the position of the sMAR at the 5 side of the reporter gene. However, variation of the detected transgene expression was significant in all transformed plant populations, irrespective of the construct used.

Ograniczanie wyników

4 Acta Biochimica Polonica

1 Adamiec R.

1 Augustyniak J.

1 Avril-Fournout N.

1 Bellis M.

1 Deschavanne P.

1 Filipski J.

1 Gawlowska M.

1 Jarmolowski A.

1 Jullien N.

1 Markiewicz E.

1 Miassod R.

1 Nowak W.

1 Rzepecki R.

1 Svetlova E.

1 Szopa J.

1 2001

1 1996

2 1995

New approaches to the mapping of chromosomal domains

SARs on an 835 kb DNA fragment from the Drosophila genome

Interaction of the Pisum sativum nuclear matrix proteins with SAR DNA

Effect of nuclear matrix attachment regions on transgene expression in tobacco plants