The Molecular Nature of Mutants Induced by X Rays Is Altered by the Presence of the Radioprotector Cysteamine

The molecular structure of mutants induced in human lymphoblast cells by 500 cGy X rays in the presence of the radioprotector cysteamine (25 mM) has been compared with that induced by an equally mutagenic treatment of 150 cGy X rays alone. Sets of mutants at the hypoxanthine-guanine phosphoribosyl t...

Full description

Saved in:
Bibliographic Details
Published in:Radiation research 1989-05, Vol.118 (2), p.324-329
Main Authors: Liber, Howard L., Benforado, Katherine, Little, John B.
Format: Article
Language:English
Subjects:
Amines
Biological and medical sciences
Biological effects of radiation
Blotting, Southern
Cell Line
Cell Survival - drug effects
Cell Survival - radiation effects
Cysteamine - pharmacology
Dosage
Dose response relationship
Fundamental and applied biological sciences. Psychology
Gene deletion
Genetic loci
Genetic mutation
Humans
Hypoxanthine Phosphoribosyltransferase
Hypoxia
In Vitro Techniques
Irradiation
Mutation
Point mutation
Radiation Genetics
Radiosensitizing agents. Photosensitizing agents. Thermosensitizing agents
Solar X rays
Tissues, organs and organisms biophysics
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The molecular structure of mutants induced in human lymphoblast cells by 500 cGy X rays in the presence of the radioprotector cysteamine (25 mM) has been compared with that induced by an equally mutagenic treatment of 150 cGy X rays alone. Sets of mutants at the hypoxanthine-guanine phosphoribosyl transferase locus were analyzed by Southern blot. Of 24 mutants induced by X rays in the presence of cysteamine, 67% exhibited no change in the restriction fragment pattern and thus were defined as point mutations; 8% appeared to be total gene deletions and 25% were partial deletions or rearrangements. In contrast, among 28 mutants induced by X rays alone (Liber et al., Mutat. Res. 178, 143-153 (1987)), 46% were point mutations, while 50% were total gene deletions and only 1 mutant (4%) was a partial deletion or rearrangement. Thus mutants isolated in the presence of cysteamine consisted of more point mutations and partial deletions/rearrangements, and considerably fewer total gene deletions. These results suggest that cysteamine may protect selectively against processes which lead to large-scale molecular changes.
ISSN:0033-7587
1938-5404
DOI:10.2307/3577446