Csm3, Tof1, and Mrc1 Form a Heterotrimeric Mediator Complex That Associates with DNA Replication Forks

Mrc1 (mediator of replication checkpoint), Tof1 (topoisomerase I interacting factor), and Csm3 (chromosome segregation in meiosis) are checkpoint-mediator proteins that function during DNA replication and activate the effector kinase Rad53. We reported previously that Mrc1 and Tof1 are constituents...

Full description

Saved in:
Bibliographic Details
Published inThe Journal of biological chemistry Vol. 284; no. 49; pp. 34355 - 34365
Main Authors Bando, Masashige, Katou, Yuki, Komata, Makiko, Tanaka, Hirokazu, Itoh, Takehiko, Sutani, Takashi, Shirahige, Katsuhiko
Format Journal Article
LanguageEnglish
Published United States Elsevier Inc 04.12.2009
American Society for Biochemistry and Molecular Biology
Subjects
Animals
Baculovirus
Cell Cycle Proteins - metabolism
Cell Line
Checkpoint Kinase 2
DNA Replication
DNA, Fungal - metabolism
DNA-Binding Proteins - metabolism
DNA: , Repair, Recombination, and Chromosome Dynamics
Gene Expression Regulation, Fungal
Hydroxyurea - chemistry
Insecta
Models, Genetic
Protein-Serine-Threonine Kinases - metabolism
Saccharomyces cerevisiae - genetics
Saccharomyces cerevisiae - metabolism
Saccharomyces cerevisiae Proteins - metabolism
Signal Transduction
Online AccessGet full text

Cover

More Information
Summary:Mrc1 (mediator of replication checkpoint), Tof1 (topoisomerase I interacting factor), and Csm3 (chromosome segregation in meiosis) are checkpoint-mediator proteins that function during DNA replication and activate the effector kinase Rad53. We reported previously that Mrc1 and Tof1 are constituents of the replication machinery and that both proteins are required for the proper arrest and stabilization of replication forks in the presence of hydroxyurea. In our current study, we show that Csm3 is a component of moving replication forks and that both Tof1 and Csm3 are specifically required for the association of Mrc1 with these structures. In contrast, the deletion of mrc1 did not affect the association of Tof1 and Csm3 with the replication fork complex. In agreement with previous observations in yeast cells, the results of a baculovirus coexpression system showed that these three proteins interact directly with each other to form a mediator complex in the absence of replication forks.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
Global Center of Excellence postdoctoral fellows.
Both authors contributed equally to this work.
ISSN:0021-9258
1083-351X
DOI:10.1074/jbc.M109.065730