IDENTIFICATION OF GENETIC LESIONS LEADING TO MUTATIONS

STRATAGENE CLONING SYSTEMS HAS INITIATED DEVELOPMENT OF A SHUTTLE VECTOR SYSTEM FOR THE DETECTION AND CHARACTERIZATIONOF CHEMICAL-INDUCED MUTATIONS IN TRANSGENIC MICE. MOUSE STRAINS HAVE BEEN DEVELOPED WITH AN INTEGRATED BACTERIOPHAGELAMBDA GENOME CONTAINING TARGET GENES THAT PERMIT RAPID DETECTION OF MUTATIONS. SEVERAL MODIFICATIONS OF THIS INTEGRATED LAMBDA VECTOR ARE PROPOSED THAT WILL ALLOW RAPID DNA SEQUENCE ANALYSIS OF MUTATIONS WITHIN THE TARGET GENE (LAC 1 REPRESSOR GENE). AFTER EXPOSURE TO A MUTAGEN, DNA SAMPLES ARE PREPARED FROM MOUSE TISSUES. PHAGE DNA IS RECOVERED DIRECTLY FROM THE MOUSE GENOMIC DNA UTILIZING STRATAGENE CLONING SYSTEMS' LAMBDA PACKAGING EXTRACTS. AFTER PLATING, PHAGE-CONTAINING MUTATIONS WITHIN THE TARGET ARE EASILY IDENTIFIED BY COLOR ASSAY. NEXT, THE MUTANT TARGET GENE IS AUTOMATICALLY EXCISED FROM THE LAMBDA PHAGE AND CONVERTED INTO A PLASMID UTILIZING SPECIFIC SITES IN THE LAMBDA PHAGE AND REPLICATIONPROTEINS DERIVED FROM THE BACTERIOPHAGE M13. THE CLASS OF VECTORS INCORPORATING THIS CONVERSION PROCESS HAS BEEN TERMED LAMBDA ZAP. THE NEW MUTAGENIC TEST VECTOR WILL BE CONSTRUCTED AND THEN MICROINJECTED INTO MOUSE EMBRYOS. MOUSE STRAINS CONTAINING THIS NOVEL SHUTTLE VECTOR WILL BE USED FOR RAPID, DETAILED IN VIVO ANALYSIS OF SUSPECTED CHEMICAL MUTAGENS.