Loading…

Inhibition of Nucleolar Reformation after Microinjection of Antibodies to RNA Polymerase I into Mitotic Cells

The formation of daughter nuclei and the reformation of nucleolar structures was studied after microinjection of antibodies to RNA polymerase I into dividing cultured cells ( PtK2). The fate of several nucleolar proteins representing the three main structural subcomponents of the nucleolus was exami...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of cell biology 1987-10, Vol.105 (4), p.1483-1491
Main Authors: Benavente, Ricardo, Rose, Kathleen M., Reimer, Georg, Hügle-Dörr, Barbara, Scheer, Ulrich
Format: Article
Language:English
Subjects:
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The formation of daughter nuclei and the reformation of nucleolar structures was studied after microinjection of antibodies to RNA polymerase I into dividing cultured cells ( PtK2). The fate of several nucleolar proteins representing the three main structural subcomponents of the nucleolus was examined by immunofluorescence and electron microscopy. The results show that the RNA polymerase I antibodies do not interfere with normal mitotic progression or the early steps of nucleologenesis, i.e., the aggregation of nucleolar material into prenucleolar bodies. However, they inhibit the telophasic coalescence of the prenucleolar bodies into the chromosomal nucleolar organizer regions, thus preventing the formation of new nucleoli. These prenucleolar bodies show a fibrillar organization that also compositionally resembles the dense fibrillar component of interphase nucleoli. We conclude that during normal nucleologenesis the dense fibrillar component forms from preformed entities around nucleolar organizer regions, and that this association seems to be dependent on the presence of an active form of RNA polymerase I.
ISSN:0021-9525
1540-8140
DOI:10.1083/jcb.105.4.1483