Ataxia-telangiectasia cell extracts confer radioresistant DNA synthesis on control cells

Journal Article · Tue Apr 01 04:00:00 EST 1986 · Exp. Cell Res.; (United States)

DOI:https://doi.org/10.1016/0014-4827(86)90065-0· OSTI ID:5738841

Mohamed, R; Lavin, M F

We have investigated in greater detail the radioresistant DNA synthesis universally observed in cells from patients with ataxia-telangiectasia (A-T). The approach employed in this study was to permeabilize cells with lysolecithin after gamma-irradiation and thus facilitate the introduction of cell extract into these cells. This permeabilization can be reversed by diluting the cells in growth medium. Cells treated in this way show the characteristic inhibition (control cells) or lack of it (A-T cells) after exposure to ionizing radiation. Introduction of A-T cells extracts into control cells prevented the radiation-induced inhibition of DNA synthesis normally observed in these cells. A-T cell extracts did not change the level of radioresistant DNA synthesis in A-T cells. Control cell extracts on the other hand did not influence the pattern of inhibition of DNA synthesis in either cell type. It seems likely that the agent involved is a protein because of its heat lability and sensitivity to trypsin digestion. It has a molecular weight (MW) in the range 20-30 000 D. The development of this assay system for a factor conferring radioresistant DNA synthesis on control cells provides a means of purifying this factor, and ultimately an approach to identifying the gene responsible.

• Research Organization: Univ. of Queensland, Brisbane, Australia
• OSTI ID: 5738841
• Journal Information: Exp. Cell Res.; (United States), Journal Name: Exp. Cell Res.; (United States) Vol. 2; ISSN ECREA
• Country of Publication: United States
• Language: English

Related Subjects

560121* -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CELL CULTURES
DISEASES
DNA
DNA REPLICATION
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
IONIZING RADIATIONS
MOLECULAR WEIGHT
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PATIENTS
PROTEINS
RADIATION PROTECTION
RADIATIONS
RADIOSENSITIVITY
RADIOSENSITIVITY EFFECTS
VASCULAR DISEASES