Quantitative kinetic analysis of nucleolar breakdown and reassembly during mitosis in live human cells.
One of the great mysteries of the nucleolus surrounds its disappearance during mitosis and subsequent reassembly at late mitosis. Here, the relative dynamics of nucleolar disassembly and reformation were dissected using quantitative 4D microscopy with fluorescent protein-tagged proteins in human stable cell lines. The data provide a novel insight into the fates of the three distinct nucleolar subcompartments and their associated protein machineries in a single dividing cell. Before the onset of nuclear envelope (NE) breakdown, nucleolar disassembly started with the loss of RNA polymerase I subunits from the fibrillar centers. Dissociation of proteins from the other subcompartments occurred with faster kinetics but commenced later, coincident with the process of NE breakdown. The reformation pathway also follows a reproducible and defined temporal sequence but the order of reassembly is shown not to be dictated by the order in which individual nucleolar components reaccumulate within the nucleus after mitosis.
Leung
Anthony Kar Lun
AK
Division of Gene Regulation and Expression, School of Life Sciences, Wellcome Trust Biocentre, University of Dundee, Dundee DD1 5EH, Scotland, UK.
Gerlich
Daniel
D
Miller
Gail
G
Lyon
Carol
C
Lam
Yun Wah
YW
Lleres
David
D
Daigle
Nathalie
N
Zomerdijk
Joost
J
Ellenberg
Jan
J
Lamond
Angus I
AI
D002466:Cell Nucleolus / Q000378:metabolism*; D005456:Fluorescent Dyes; D006367:HeLa Cells; D006801:Humans; D021621:Imaging, Three-Dimensional; D007150:Immunohistochemistry; D007700:Kinetics; D008938:Mitosis; D008954:Models, Biological; D009685:Nuclear Envelope / Q000378:metabolism; D009697:Nucleolus Organizer Region / Q000378:metabolism; D011233:Precipitin Tests; D012318:RNA Polymerase I / Q000378:metabolism
D005456:Fluorescent Dyes; D012318:RNA Polymerase I