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Functional aspects of nuclear matrix

100%

Wanka F.

Acta Biochimica Polonica

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1995

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tom 42

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nr 2

A model is proposed of the way in which the unwinding of the chromosomal DNA loops is controlled during DNA replication. It is based on the observation of a permanent binding of replication origins to the nuclear matrix and of a transient attachment of replicating DNA regions to sites in the immediate neighbourhood. DNA unwinding is controlled while the replicating loops are reeled through the replication binding sites. Also a mechanism is proposed to explain how the once-per-cycle replication of individual replicons can be controlled. DNA synthesis is initiated at single-stranded loops exposed by tandemly repeated DNA sequences at the replication origins. The single-stranded loops turn into fully double-stranded DNA during replication, becoming inaccessible for a second initiation during the same cell cycle. The configuration competent for initiation is restored by specific protein-DNA rearrangements coupled to mitotic condensation of the matrix into chromosomal scaffolds and its reversal.

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The nuclear protein p30 specifically interacts with a nuclear matrix attachment region from the rat genome

100%

Fedorov A., Lukyanov D., Rogolinski J., Widlak P., Podgornaya O., Rzeszowska-Wolny J.

Cellular and Molecular Biology Letters

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2004

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tom 09

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nr 1

In our previous study, a 454 bp DNA fragment was isolated from rat genomic DNA as an element which interacts with nuclear matrix proteins, i.e. a Matrix Associated Region (MAR). Computer analyses revealed that the right half of this fragment, named RME (Rat MAR Element), possesses a high matrix association potential and is likely to be responsible for the matrix association of the whole sequence. RME was used as a probe in an electrophoretic mobility shift assay (EMSA), and with the use of Southwestern blotting, a rat liver nuclear protein which binds specifically to it was identified. Its molecular mass was estimated by SDS-PAGE as 30 kDa (p30). Polyclonal antibodies raised against protein-RME complexes caused a super-shift of specific complexes in EMSA, and bound to p30 in nuclear extracts of rat liver in Western blotting. The immunofluorescence labelling of a rat embryonic fibroblast cell monolayer with anti-p30 antibody revealed a mainly intranuclear pattern of staining.

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New approaches to the mapping of chromosomal domains

84%

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.

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Poly[ADP-ribosyl]ation of proteins associated with nuclear matrix in rat testis

84%

Quesada P., d'Erme M., Atorino L., Faraone-Mennella M. R., Caiafa P., Farina B.

Acta Biochimica Polonica

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1995

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tom 42

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nr 2

We have previously demonstrated that a significant percentage of poly(ADPR) polymerase is present, as a tightly-bound form, at the third level of chromatin organisation defined by chromosomal loops and nuclear matrix. The present work is focused on the study of poly(ADP-ribosyl)ation of proteins present in these nuclear subfractions. It has been shown that, due to the action of poly(ADPR) polymerase, the ADP-ribose moiety of [14C]NAD is transferred to both loosely-bound and tightly-bound chromosomal proteins, which in consequence are modified by chain polymers of ADP-ribose of different lengths. Moreover, histone-like proteins seem to be ADP-ribosylated in chromosomal loops and nuclear matrix associated regions of DNA loops (MARS). A hypothesis can be put forward that the ADP-ribosylation system is functionally related to the nuclear processes, actively coordinated by the nuclear matrix.

Ograniczanie wyników

3 Acta Biochimica Polonica

1 Cellular and Molecular Biology Letters

1 Atorino L.

1 Avril-Fournout N.

1 Bellis M.

1 Caiafa P.

1 Deschavanne P.

1 Faraone-Mennella M. R.

1 Farina B.

1 Fedorov A.

1 Filipski J.

1 Lukyanov D.

1 Podgornaya O.

1 Quesada P.

1 Rogolinski J.

1 Rzeszowska-Wolny J.

1 Svetlova E.

1 Wanka F.

1 Widlak P.

1 d'Erme M.

1 2004

1 1996

2 1995

Functional aspects of nuclear matrix

The nuclear protein p30 specifically interacts with a nuclear matrix attachment region from the rat genome

New approaches to the mapping of chromosomal domains

Poly[ADP-ribosyl]ation of proteins associated with nuclear matrix in rat testis