Cyclin F-mediated degradation of ribonucleotide reductase M2 controls genome integrity and DNA repair.

F-box proteins are the substrate binding subunits of SCF (Skp1-Cul1-F-box protein) ubiquitin ligase complexes. Using affinity purifications and mass spectrometry, we identified RRM2 (the ribonucleotide reductase family member 2) as an interactor of the F-box protein cyclin F. Ribonucleotide reductase (RNR) catalyzes the conversion of ribonucleotides to deoxyribonucleotides (dNTPs), which ...
are necessary for both replicative and repair DNA synthesis. We found that, during G2, following CDK-mediated phosphorylation of Thr33, RRM2 is degraded via SCF(cyclin F) to maintain balanced dNTP pools and genome stability. After DNA damage, cyclin F is downregulated in an ATR-dependent manner to allow accumulation of RRM2. Defective elimination of cyclin F delays DNA repair and sensitizes cells to DNA damage, a phenotype that is reverted by expressing a nondegradable RRM2 mutant. In summary, we have identified a biochemical pathway that controls the abundance of dNTPs and ensures efficient DNA repair in response to genotoxic stress.
Mesh Terms:
Amino Acid Motifs, Cell Cycle Proteins, Cell Line, Tumor, Cell Nucleus, Cyclins, DNA Damage, DNA Repair, Down-Regulation, G2 Phase, Genomic Instability, Humans, Protein-Serine-Threonine Kinases, Ribonucleoside Diphosphate Reductase
Cell
Date: May. 25, 2012
Download Curated Data For This Publication
139047
Switch View:
  • Interactions 5
  • PTM Genes 1