HMGN dynamics and chromatin function.
Recent studies indicate that most nuclear proteins, including histone H1 and HMG are highly mobile and their interaction with chromatin is transient. These findings suggest that the structure of chromatin is dynamic and the protein composition at any particular chromatin site is not fixed. Here we discuss how the dynamic behavior of the nucleosome binding HMGN proteins affects the structure and function of chromatin. The high intranuclear mobility of HMGN insures adequate supply of protein throughout the nucleus and serves to target these proteins to their binding sites. Transient interactions of the proteins with nucleosomes destabilize the higher order chromatin, enhance the access to nucleosomal DNA, and impart flexibility to the chromatin fiber. While roaming the nucleus, the HMGN proteins encounter binding partners and form metastable multiprotein complexes, which modulate their chromatin interactions. Studies with HMGN proteins underscore the important role of protein dynamics in chromatin function.
Catez
Frédéric
F
Protein Section, Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Lim
Jae-Hwan
JH
Hock
Robert
R
Postnikov
Yuri V
YV
Bustin
Michael
M
D000818:Animals; D001665:Binding Sites; D002843:Chromatin / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D024001:HMGN Proteins / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D018613:Microscopy, Confocal; D008854:Microscopy, Electron; D008938:Mitosis / Q000502:physiology; D008954:Models, Biological; D008958:Models, Molecular; D009707:Nucleosomes / Q000378:metabolism / Q000648:ultrastructure; D011485:Protein Binding
D002843:Chromatin; D024001:HMGN Proteins; D006657:Histones; D009707:Nucleosomes; D004247:DNA