Alternative DNA Damage Checkpoint Pathways in Eukaryotes

Abstract

Our laboratory has previously shown that a human cDNA CHES1 (checkpoint suppressor 1) suppresses multiple mutants along the primary DNA damage checkpoint pathway in Saccharomyces cerevisiae. Our hypothesis is that CHES1 does so by activating an alternative DNA damage-induced checkpoint pathway. The objectives of this project are to identify, characterize, and clone the genes in this pathway, and to isolate human homologs and analyze their structure and expression in human breast cancers. We have constructed a temperature and UV-sensitive strain SCP2. Both phenotypes can be partially rescued by CHES1. Approximately 220,000 colonies of SCP2 have been mutagenized and screened for the mutant phenotypes in the presence of CHES1. Three chb (for checkpoint bypass) mutants were isolated. Among them, chbl3 has a strong mutant phenotype and both chbl6 and chb57 are weaker alleles. We have confirmed that all three mutants are recessive and belong to the same complementation group. In the process of cloning this gene we encountered some difficulties, therefore we also tried the candidate gene and the yeast 2-hybrid approaches but with no success. In this report, we proposed alternative methods in cloning the new pathway genes. We will also focus on the characterization of CHES1 in mammalian cells.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 2000
Accession Number
ADA381190

Entities

People

  • Yi-Chen Li

Organizations

  • Baylor College of Medicine

Tags

DTIC Thesaurus Topics

  • Breast Cancer
  • Cells
  • Diseases And Disorders
  • Eukaryotes
  • Fungi
  • Genes
  • Genetic Structures
  • Genetics
  • Genome
  • Materials
  • Neoplasms
  • Phenotypes
  • Proteins

Fields of Study

  • Biology

Readers

  • Cellular and Molecular Pathways of Apoptosis.
  • Molecular Biology and Genetics
  • Molecular Genetics