PMID- 10504331
OWN - NLM
STAT- MEDLINE
DCOM- 19991217
LR  - 20181201
IS  - 0021-9533 (Print)
IS  - 0021-9533 (Linking)
VI  - 112 ( Pt 19)
DP  - 1999 Oct
TI  - The mitotically phosphorylated form of the transcription termination factor TTF-1
      is associated with the repressed rDNA transcription machinery.
PG  - 3259-68
AB  - The transcription termination factor TTF-1 exerts two functions in ribosomal gene
      (rDNA) transcription: facilitating initiation and mediating termination of
      transcription. Using HeLa cells, we show that TTF-1 protein is colocalized with
      the active transcription machinery in the nucleolus and also with the inactive
      machinery present in certain mitotic nucleolar organizer regions (NORs) when rDNA
      transcription is repressed. We also show that TTF-1 is specifically
      phosphorylated during mitosis in a manner dependent on the cdc2-cyclin B kinase
      pathway and on an okadaic acid-sensitive phosphatase. Interestingly, the
      mitotically phosphorylated form of TTF-1 appearing at the G(2)/M transition phase
      was more easily solubilized than was the interphase form. This indicates that the
      chromatin-binding affinity of TTF-1 appears to be different in mitotic
      chromosomes compared to the interphase nucleolus. Correlated with this, the other
      DNA-binding factor, UBF, which interferes with chromatin conformation in the rDNA
      promoter, was more strongly bound to rDNA during mitosis than at interphase. The 
      reorganization of the mitotic rDNA promoter might be induced by phosphorylation
      of certain components of the rDNA transcription machinery and participate in
      silencing of rDNA during mitosis.
FAU - Sirri, V
AU  - Sirri V
AD  - Institut Jacques Monod, UMR 7592, Paris, France.
FAU - Roussel, P
AU  - Roussel P
FAU - Hernandez-Verdun, D
AU  - Hernandez-Verdun D
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - J Cell Sci
JT  - Journal of cell science
JID - 0052457
RN  - 0 (Autoantibodies)
RN  - 0 (DNA, Ribosomal)
RN  - 0 (DNA-Binding Proteins)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (NKX2-1 protein, human)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Pol1 Transcription Initiation Complex Proteins)
RN  - 0 (Purines)
RN  - 0 (Thyroid Nuclear Factor 1)
RN  - 0 (Transcription Factors)
RN  - 0 (transcription factor UBF)
RN  - 0ES1C2KQ94 (Roscovitine)
RN  - EC 2.7.11.22 (CDC28 Protein Kinase, S cerevisiae)
RN  - EC 2.7.7.6 (RNA Polymerase I)
SB  - IM
MH  - Antibody Specificity
MH  - Autoantibodies/immunology/pharmacology
MH  - CDC28 Protein Kinase, S cerevisiae/antagonists & inhibitors/metabolism
MH  - Cell Cycle/drug effects/physiology
MH  - Chromosomes/genetics
MH  - DNA, Ribosomal/*metabolism
MH  - DNA-Binding Proteins/analysis/metabolism
MH  - Enzyme Inhibitors/pharmacology
MH  - Gene Expression Regulation, Enzymologic/physiology
MH  - HeLa Cells
MH  - Humans
MH  - Interphase/physiology
MH  - Mitosis/*physiology
MH  - Nuclear Proteins/analysis/immunology/*metabolism
MH  - Nucleolus Organizer Region/chemistry/enzymology
MH  - Phosphorylation
MH  - *Pol1 Transcription Initiation Complex Proteins
MH  - Purines/pharmacology
MH  - RNA Polymerase I/analysis
MH  - Roscovitine
MH  - Thyroid Nuclear Factor 1
MH  - Transcription Factors/analysis/immunology/*metabolism
MH  - Transcriptional Activation/*physiology
EDAT- 1999/10/03 00:00
MHDA- 1999/10/03 00:01
CRDT- 1999/10/03 00:00
PHST- 1999/10/03 00:00 [pubmed]
PHST- 1999/10/03 00:01 [medline]
PHST- 1999/10/03 00:00 [entrez]
PST - ppublish
SO  - J Cell Sci. 1999 Oct;112 ( Pt 19):3259-68.