1) STUDY OF MOLECULAR INTERACTIONS OF ENVIRONMENTAL MUTAGENS AND CARCINOGENS AT DNA LEVEL. 2) TO RELATE BIOLOGICAL CONSEQUENCES OF CHEMICAL MUTAGENS TO THE EXTENT AND SITE OF REACTION BETWEEN THE MUTAGENS AND DNA. 3) DEVELOPMENT AND VALIDATION OF METHODS TO IDENTIFY NON-GENOTOXIC CARCINOGENS. 4) DEVELOPMENT AND VALIDATION OF ASSAYS TO EVALUATE CHEMICALS CAPABLE OF INDUCING GENOMIC MUTATIONS.
A package of chemicals, with a proposed role in the production of cells with aberrant chromosome numbers, were investigated using a range of techniques. Yeast cultures, such as strain D6, responded to some but not to all of the test chemicals. The differential staining assay appeared to be a sensitive method for detecting the ability of the test chemicals to induce damage to a variety of cellular targets. The in vitro micronucleus assay superficially appeared to be a convenient assay system, but was subject to complications due to cell toxicity and with some chemicals may be prone to technical artefacts.
1)THE INCIDENCE AND NATURE OF LARGE DNA ADDUCTS IS STUDIED BY HPLC AND MASS SPECTROMETRY. THEIR REPAIR IS EXAMINED IN BOTH NORMAL HUMAN CELLS AND IN CELLS FROM PATIENTS SUFFERING FROM CANCER PRONE DISEASES. THE WORK WILL AIM TO CHARACTERIZE THE MECHANISMS BY WHICH SUCH LESIONS ARE RECOGNISED AND REPAIRED.
2) THE RELATIONSHIP BETWEEN DNA DAMAGE AND VARIOUS GENETIC ENDPOINTS (E.G. POINT MUTATION, RECOMBINATION, ANEUPLOIDY) IS STUDIED IN THE YEAST SACCHAROMYCES CEREVISIAE. PARTICULAR ATTENTION IS GIVEN TO THE CONTRIBUTION OF INDIVIDUAL LESIONS TO THE INDUCTION OF THE DIFFERENT ENDPOINTS.
3) THE BASIC BIOLOGY (E.G. SPINDLE FIDELITY, CELL DIVISION, CENTROMERE FIDELITY, CHROMOSOME KARYOTYPE AND ANALYSIS OF ACTIVATED ONCOGENES) IS STUDIED IN CULTURES ISOLATED AT VARIOUS STAGES OF IN-VITRO TRANSFORMATION.
4) THE CONTRACTANT COORDINATES THE PURCHASE AND DISTRIBUTION OF THE CHEMICALS, PROVIDES APPROPRIATE MAMMALIAN CELL CULTURES AND FACILITIES FOR THE COLLECTION AND ANALYSIS OF TEST DATA. THE CONTRACTANT ALSO PERFORMS LABORATORY STUDIES ON THE FOLLOWING ASSAYS: I)IN-VITRO MICROTUBULE POLYMERIZATION; II)CELL DIVISION MORPHOLOGY; III)CHARACTERIZATION OF MICRONUCLEI, AND IV) CHROMOSOME KARYOTYPING.