Reconstitution of a MEC1-independent checkpoint in yeast by expression of a novel human fork head cDNA

Mol Cell Biol. 1997 Jun;17(6):3037-46. doi: 10.1128/MCB.17.6.3037.

Abstract

A novel human cDNA, CHES1 (checkpoint suppressor 1), has been isolated by suppression of the mec1-1 checkpoint mutation in Saccharomyces cerevisiae. CHES1 suppresses a number of DNA damage-activated checkpoint mutations in S. cerevisiae, including mec1, rad9, rad24, dun1, and rad53. CHES1 suppression of sensitivity to DNA damage is specific for checkpoint-defective strains, in contrast to DNA repair-defective strains. Presence of CHES1 but not a control vector resulted in G2 delay after UV irradiation in checkpoint-defective strains, with kinetics, nuclear morphology, and cycloheximide resistance similar to those of a wild-type strain. CHES1 can also suppress the lethality, UV sensitivity, and G2 checkpoint defect of a mec1 null mutation. In contrast to this activity, CHES1 had no measurable effect on the replication checkpoint as assayed by hydroxyurea sensitivity of a mec1 strain. Sequence analysis demonstrates that CHES1 is a novel member of the fork head/Winged Helix family of transcription factors. Suppression of the checkpoint-defective phenotype requires a 200-amino-acid domain in the carboxy terminus of the protein which is distinct from the DNA binding site. Analysis of CHES1 activity is most consistent with activation of an alternative MEC1-independent checkpoint pathway in budding yeast.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cell Cycle
  • Cell Cycle Proteins*
  • DNA Damage / genetics
  • DNA Repair*
  • DNA, Complementary / chemistry
  • DNA, Complementary / isolation & purification
  • Forkhead Transcription Factors
  • Fungal Proteins / genetics*
  • Fungal Proteins / metabolism
  • G2 Phase
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Kinetics
  • Molecular Sequence Data
  • Mutagenesis / drug effects
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Open Reading Frames
  • Promoter Regions, Genetic
  • Protein-Serine-Threonine Kinases
  • Radiation Tolerance / genetics
  • Repressor Proteins / genetics*
  • Repressor Proteins / metabolism
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins*
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Ultraviolet Rays

Substances

  • Cell Cycle Proteins
  • DNA, Complementary
  • FOXN3 protein, human
  • Forkhead Transcription Factors
  • Fungal Proteins
  • Intracellular Signaling Peptides and Proteins
  • Nuclear Proteins
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • MEC1 protein, S cerevisiae
  • Protein-Serine-Threonine Kinases

Associated data

  • GENBANK/U68723