First published online March 8, 2006
Journal of Cell Science 119, 604e (2006)
© The Company of Biologists Limited
PML's out-of-body experience
Promyelocytic leukaemia (PML) bodies are chromatin-associated sites of DNA metabolism present in the nuclei of mammalian cells. For much of the cell cycle, PML bodies are stable but David Bazett-Jones and his team now describe how they change during early S phase, mitosis and early G1 phase. On p. 1026, the authors show that PML bodies become distorted and undergo fission to form microbodies as cells enter S phase. Noting that PML bodies remain associated with chromatin and double in number during S phase, the authors suggest these alterations in their behaviour reflect changes in the topology of DNA as it replicates. On p. 1034, the authors go on to investigate the biochemical and morphological changes in PML bodies during mitosis. They find that the PML protein that defines these structures is recycled from one cell cycle to the next via chromatin-associated and freely diffusing mitotic accumulations of PML protein (MAPPs) - structures that contain the PML protein but lack several PML body components. The authors propose that, in early G1 phase, chromatin-associated MAPPs provide a seed for the reformation of PML nuclear bodies through the redistribution of PML protein from cytoplasmic MAPPs. They suggest that other nuclear bodies may use a similar mechanism to partition during mitosis.
Related articles in JCS:
- The number of PML nuclear bodies increases in early S phase by a fission mechanism
- Graham Dellaire, Reagan W. Ching, Hesam Dehghani, Ying Ren, and David P. Bazett-Jones
JCS 2006 119: 1026-1033.
[Abstract]
[Full Text]
- Mitotic accumulations of PML protein contribute to the re-establishment of PML nuclear bodies in G1
- Graham Dellaire, Christopher H. Eskiw, Hesam Dehghani, Reagan W. Ching, and David P. Bazett-Jones
JCS 2006 119: 1034-1042.
[Abstract]
[Full Text]
