Histochemistry and Cell Biology

, Volume 125, Issue 1, pp 103–117

The microarchitecture of DNA replication domains

  • Anatoly A. Philimonenko
  • Zdeněk Hodný
  • Dean A. Jackson
  • Pavel Hozák
Original paper

DOI: 10.1007/s00418-005-0090-0

Cite this article as:
Philimonenko, A.A., Hodný, Z., Jackson, D.A. et al. Histochem Cell Biol (2006) 125: 103. doi:10.1007/s00418-005-0090-0


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 α, 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 α, 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.


DNA replication Cell nucleus Ultrastructure Nuclear bodies Replication factory Replication foci Nuclear proteins 



Proliferating cell nuclear antigen


Green fluorescent protein


Replication bodies


Replication foci

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Anatoly A. Philimonenko
    • 1
  • Zdeněk Hodný
    • 1
  • Dean A. Jackson
    • 2
  • Pavel Hozák
    • 1
  1. 1.Institute of Experimental MedicineAcademy of Sciences of the Czech RepublicPrague 4-KrčCzech Republic
  2. 2.Faculty of Life Sciences, Jackson’s MillUniversity of Manchester ManchesterUK

Personalised recommendations