title: A mutant lymphoma cell line with a defective Thy-1 glycoprotein gene.
abstract: We characterized a mutant T-cell lymphoma line selected for the inability to express the Thy-1 glycoprotein. This cell line is a member of the D complementation class of Thy-1- somatic cell mutants, and it lacks detectable cell-surface Thy-1.1 glycoprotein and detectable cytoplasmic Thy-1 mRNA. Southern blot analysis using a number of probes isolated from the cloned Thy-1.2 gene demonstrated that, in the mutant, one copy of the Thy-1 gene is absent from the genome and the other has undergone rearrangement. This rearrangement results from a deletion of the 5' portion of the gene removing the first two alternate exons and promoters and a portion of the second intron. The deletion breakpoint within the mutant Thy-1 gene was localized to within 400 nucleotides by Southern blot analysis. The breakpoint is near two classes of mouse repetitive elements-a mouse B1-family repetitive element and a simple repetitive sequence-suggesting a mechanism of rearrangement leading to the mutation. Southern blot analysis demonstrated that two closely linked molecular markers on chromosome 9 are unaltered, demonstrating that the deletion in this mutant cell line is subchromosomal.
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics*; D000954:Antigens, Surface / Q000235:genetics*; D002460:Cell Line; D002872:Chromosome Deletion; D005796:Genes; D006023:Glycoproteins / Q000235:genetics; D008223:Lymphoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D051379:Mice; D008806:Mice, Inbred AKR / Q000235:genetics / Q000276:immunology; D009363:Neoplasm Proteins / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D012091:Repetitive Sequences, Nucleic Acid; D018800:Thy-1 Antigens
chemical_list: D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D006023:Glycoproteins; D009363:Neoplasm Proteins; D018800:Thy-1 Antigens