title: X-ray-induced mutations in mouse embryonic stem cells.
abstract: Deletion complexes consisting of multiple chromosomal deletions induced at single loci can provide a means for functional analysis of regions spanning several centimorgans in model genetic systems. A strategy to identify and map deletions at any cloned locus in the mouse is described here. First, a highly polymorphic, germ-line competent F1(129/Sv-+Tyr+p x CAST/Ei) mouse embryonic stem cell line was established. Then, x-ray and UV-induced mutagenesis was performed to determine the feasibility of generating deletion complexes throughout the mouse genome. Reported here are the selection protocols, induced mutation frequencies, cytogenetic and extensive molecular analysis of mutations at the X-chromosome-linked hypoxanthine phosphoribosyltransferase (Hprt) locus and at the neural cell adhesion molecule (Ncam) locus located on chromosome 9. Mutation analysis with PCR-based polymorphic microsatellite markers revealed deletions of <3 cM at the Hprt locus, whereas results consistent with deletions covering >28 cM were observed at the Ncam locus. Fluorescence in situ hybridization with a chromosome 9 paint revealed that some of the Ncam deletions were accompanied by complex chromosome rearrangements. In addition, deletion mapping in combination with loss of heterozygosity of microsatellite markers revealed a putative haploinsufficient region distal to Ncam. These data indicate that it is feasible to generate x-ray-induced deletion complexes in mouse embryonic stem cells.
authors.affiliation: Department of Genetics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-4955, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Thomas
authors.forename: C
authors.initials: C
authors.lastname: LaMantia
authors.forename: T
authors.initials: T
authors.lastname: Magnuson
mesh_terms: D000818:Animals; D002460:Cell Line; D002874:Chromosome Mapping; D004303:Dosage Compensation, Genetic; D004622:Embryo, Mammalian / Q000528:radiation effects*; D005260:Female; D017353:Gene Deletion; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D019656:Loss of Heterozygosity; D008297:Male; D051379:Mice; D016296:Mutagenesis; D019006:Neural Cell Adhesion Molecules / Q000235:genetics; D013234:Stem Cells / Q000528:radiation effects*; D013937:Thymidine Kinase / Q000235:genetics
chemical_list: D019006:Neural Cell Adhesion Molecules; D007041:Hypoxanthine Phosphoribosyltransferase; D013937:Thymidine Kinase