Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2006 Jan;125(1-2):103-17.
doi: 10.1007/s00418-005-0090-0. Epub 2005 Oct 25.

The microarchitecture of DNA replication domains

Anatoly A Philimonenko  1 , Zdenek Hodný, Dean A Jackson, Pavel Hozák
Affiliations

The microarchitecture of DNA replication domains

Anatoly A Philimonenko et al. Histochem Cell Biol. 2006 Jan.

Abstract

Most DNA synthesis in HeLa cell nucleus is concentrated in discrete foci. These synthetic sites can be identified by electron microscopy after allowing permeabilized cells to elongate nascent DNA in the presence of biotin-dUTP. Biotin incorporated into nascent DNA can be then immunolabeled with gold particles. Two types of DNA synthetic sites/replication factories can be distinguished at ultrastructural level: (1) electron-dense structures--replication bodies (RB), and (2) focal replication sites with no distinct underlying structure--replication foci (RF). The protein composition of these synthetic sites was studied using double immunogold labeling. We have found that both structures contain (a) proteins involved in DNA replication (DNA polymerase alpha, PCNA), (b) regulators of the cell cycle (cyclin A, cdk2), and (c) RNA processing components like Sm and SS-B/La auto antigens, p80-coilin, hnRNPs A1 and C1/C2. However, at least four regulatory and structural proteins (Cdk1, cyclin B1, PML and lamin B1) differ in their presence in RB and RF. Moreover, in contrast to RF, RB have structural organization. For example, while DNA polymerase alpha, PCNA and hnRNP A1 were diffusely spread throughout RB, hnRNP C1/C2 was found only at the very outside. Surprisingly, RB contained only small amounts of DNA. In conclusion, synthetic sites of both types contain similar but not the same sets of proteins. RB, however, have more developed microarchitecture, apparently with specific functional zones. This data suggest possible differences in genome regions replicated by these two types of replication factories.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. J Cell Biol. 1979 May;81(2):453-7 - PubMed
    1. Science. 1992 Sep 18;257(5077):1689-94 - PubMed
    1. Oncogene. 2002 Jan 21;21(4):598-610 - PubMed
    1. Nucleic Acids Res. 1978 Oct;5(10):3697-714 - PubMed
    1. J Mol Biol. 1986 Nov 5;192(1):65-76 - PubMed

Publication types

LinkOut - more resources